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VersaPulse PowerSuite Holmium 20 Watt SERVICE MANUAL
This service manual is to be used in conjunction with the operator manual for the product. The operator manual contains important information regarding instrument description, location of controls, specifications, and normal operating procedures.
LASER CLASS 4/IV Holmium:YAG: 2.1µ m, 5J Max, 600µ s pulse LASER CLASS 3A/IIIa Diode Laser: 650nm, 5mW Max, CW
VISIBLE AND INVISIBLE LASER RADIATION AVOID EYE OR SKIN EXPOSURE TO DIRECT OR SCATTERED RADIATION
CLASS 4 LASER PRODUCT per EN 60825-1/1994 CLASS IV LASER PRODUCT per 21 cfr 1040
0635-365-01 Rev. B
2400 Condensa Street Santa Clara, CA 95051 (408) 764-7000
0640-665-00 REV. A
This manual is copyrighted with all rights reserved. Under the copyright laws, this manual cannot be copied in whole or part without express written permission of Lumenis, Inc. Permitted copies must carry the same proprietary and copyright and copyright notices as were affixed to the original. Please note that while every effort has been made to ensure that the data given is accurate, the information, figures, illustrations, tables, specifications, and schematics are subject to change without notice. Lumenis and the Lumenis Logo are registered trademarks of Lumenis, Inc. Please direct all inquiries about this manual to: Lumenis, Inc. Technical Support C-35 2400 Condensa Street Santa Clara, CA 95051 (408) 764-3638
©Lumenis, Inc. 0640-665-00 REV. A
DISCLAIMER
Lumenis service manuals are written specifically for use by Lumenis service engineers who have received formal training in the servicing of Lumenis Equipment, and by customers who have taken and passed a Lumenis certification service training course for the equipment being serviced. Information on certification service training courses offered to customers can be obtained by contacting the Technical Coordinator at (800) 367-7899. Lumenis does not accept responsiblity for personal injury or property damage resulting from the servicing of Lumenis equipment by its customers or by third parties, except where such injury or property damage is a direct result of Lumenis's negligence. Customers, by accepting the service manual, agree to indemnify Lumenis against any claims alleging personal injury or property damage resulting from the servicing of Lumenis equipment by the customer or by third parties, except where such injury or property damage is a direct result of Lumenis's negligence. These limitations include situations where Lumenis personnel are advising customers on the repair of Lumenis equipment over the telephone, via fax or e-mail. The servicing of Lumenis equipment by persons who have not passed a current Lumenis certification service training course for that equipment will void Lumenis's product warranty.
VersaPulse PowerSuite Holmium 20 Watt Service Manual Disclaimer 0640-665-00 REV. A
REVISION INFORMATION
This is the REV. A release of the VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual. Contact Lumenis Technical Support to determine if this is the most current release of this service manual. Each page of this manual has a revision level at the bottom. This indicates the release level for the individual sections. Note that when the manual is updated, not all of the sections are necessarily updated, so some sections may have a revision level earlier than the release revision level for the manual (the revision level for the manual is the revision letter that appears on the cover and in the first sentence of this revision information page). The following list provides a complete list of the revision information, by section, for this release of the service manual. Cover page, copyright page, disclaimer page, this page, table of contents page(s) are all revision A with the corresponding section(s) of the manual.
SECTION 1 SECTION 2 SECTION 3 SECTION 4 SECTION 5 SECTION 6 SECTION 7
0640-665-01 0640-665-02 0640-665-03 0640-665-04 0640-665-05 0640-665-06 0640-665-07
REV. A REV. A REV. A REV. A REV. A REV. A REV. A
ECO# ECO# ECO# ECO# ECO# ECO# ECO#
NOTE: Field Service Bulletins (FSBs) released for this service manual are listed in the VersaPulse PowerSuite Holmium 20 Watt FSB Index. Each time an FSB for this manual is released or updated, the Index is also updated and distributed with the FSB. The current index is placed behind the single sheet that makes up Section 7, and the FSB's are placed in order behind the Index. Contact Lumenis Technical Support for the date of the most current FSB Index. SECTION 8 0640-665-08 REV. A
VersaPulse PowerSuite Holmium 20 Watt Service Manual Revision Information 0640-665-00 REV. A
TABLE OF CONTENTS
1.0 GENERAL INFORMATION
1.1 1.2 1.3 1.4 1.5 Use of This Manual Conventions Used in This Manual Serial Number Format Certification Compliance Service Information & FDA Compliance
2.0
INSTALLATION
2.1 2.2 2.3 Introduction Installation Procedure/Checklist Product Specifications
3.0
CALIBRATION, ALIGNMENT & ADJUSTMENT
3.1 3.2 3.3 3.4 3.5 3.6 3.7 Introduction Optical Alignment Electrical Adjustments Mechanical Adjustments Energy Calibration Operational and Safety Check Periodic Maintenance
4.0
THEORY OF OPERATION
4.1 4.2 4.3 4.4 4.5 4.6 4.7 Introduction Power Switching, Conditioning and Distribution Cooling System Control Electronics Flash Lamp Power Supply Optics Software
5.0
TROUBLESHOOTING
5.1 5.2 5.3 5.4 5.5 5.6 5.7 Overview Interior Access & Parts Location Service Mode Fault Isolation/Fault Codes Test Points & LED Arrangment Remove/Replace Procedures Troubleshooting
6.0
SELECTED PART NUMBERS VersaPulse PowerSuite Holmium 20 Watt Service Manual Table of Contents 0640-665-00 REV. A
7.0 8.0
FIELD SERVICE BULLETINS SCHEMATICS & DRAWINGS
VersaPulse PowerSuite Holmium 20 Watt Service Manual Table of Contents 0640-665-00 REV. A
1.0 GENERAL INFORMATION
1.1
USE OF THIS MANUAL
This manual contains service instructions for the Lumenis VersaPulse® PowerSuiteTM Holmium 20 Watt surgical laser. The content of this manual is intended solely for use by Lumenis Field Service Engineers and Lumenis trained and certified customer technicians. Lumenis, Inc. cannot be responsible for service or repairs attempted by uncertified persons, and the use of this manual by such persons is prohibited.
This manual is to be used in conjunction with the Lumenis Operator Manual for the VersaPulse PowerSuite Holmium 20 Watt laser. The operator manual contains important information regarding instrument description, location of controls, specifications and normal operating procedures.
As necessary, Lumenis Technical Support releases Field Service Bulletins (FSB) for the VersaPulse PowerSuite Holmium 20 Watt laser. These FSB's supplement the information in this manual. As they are released, the FSB's become a part of this manual (Section 7).
1.2
CONVENTIONS USED IN THIS MANUAL
Within the text, logic signals that are active low ("notted") will appear with an exclamation point preceding the signal name, as illustrated below.
!RESET
These signals are "active", or true, when the logic level is low. When the logic signal !RESET is low, the reset loop is "OK" and the microprocessor will reset the system. When the logic signal !RESET is high, the reset loop is not OK. In most of the schematic diagrams such signals are indicated by the usual solid line above the signal name, as illustrated below.
RESET
The schematics in this manual do not include individual numbers for the logic elements or operational amplifiers within a single component. For example, U1 which is illustrated on the next page, contains two operational amplifiers. The top op amp would be referred to as U1-1 (its output is pin 1) and the other would be referred to as U1-7. VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-01 REV. A GENERAL INFORMATION 1-1
2 3 6 5
1
U1
7
U1
1.3
SERIAL NUMBERS
Serial numbers for the VersaPulse PowerSuite Holmium 20 Watt laser are in the following format:
(TBD)
1.4
CERTIFICATION OF COMPLIANCE AND APPROVALS
The VersaPulse PowerSuite Holmium 20 Watt laser is designed and tested in accordance with Lumenis's procedures for self certification for a CE mark.
The CE mark is a certification label which allows Lumenis to sell the VersaPulse PowerSuite Holmium 20 Watt Lasers throughout the European community. This label certifies that the VersaPulse PowerSuite Holmium 20 Watt laser meets all regulations set forth by various countries in Europe. It is important to ensure that this label is on the laser chassis.
93/42/EEC 0086
The VersaPulse PowerSuite Holmium 20 Watt laser also meets UL 2601-1, IEC 601-1, EN 60601-1, EN 60601-1-2, EN 60601-1-22, CAN4/CSA-C22.2 No. 601.1-M90, CAN/CSA C22.2 No. 601.2.22-94, IEC 60285-1, CD Scheme and other applicable standards, and it bears the CE Mark. GENERAL INFORMATION 1-2 VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-00 REV. A
1.5
SERVICE INFORMATION & FDA COMPLIANCE
In compliance to the FDA, brochures and specifications sheets must include a reproduction of a complete warning logotype or Class IIa warning statement as required on the product (1040.10(h)(2)(i)). Servicing information must contain the following (1040.10(h)(2)(ii)):
· Procedures for service with appropriate warnings to avoid exposure. (Refer to Section 3)
· A schedule of maintenance to maintain the product in compliance (Refer to Section 3)
· A list of controls that could increase the level of accessible radiation.
·· The energy UP/DN buttons on the LCD touch screen display.
· Identification of removable portions of protective housings. (Refer to Section 5)
· Procedures to avoid exposure. (Refer to Section 3)
· Reproductions of required labels and warnings.
·· In the succeeding pages are illustrations of required labels and warnings applicable to this Service Manual:
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-01 REV. A
GENERAL INFORMATION 1-3
LASER CLASS 4/IV Holmium:YAG: 2.1µm, 5J Max, 600µs pulse LASER CLASS 3A/IIIa Diode Laser: 650nm, 5mW Max, CW
VISIBLE AND INVISIBLE LASER RADIATION AVOID EYE OR SKIN EXPOSURE TO DIRECT OR SCATTERED RADIATION
CLASS 4 LASER PRODUCT per EN 60825-1/1994 CLASS IV LASER PRODUCT per 21 CFR 1040
0635-365-01 Rev. B
All regulatory compliance labels including the Danger Label above are located in this area.
(REAR VIEW)
GENERAL INFORMATION 1-4
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-00 REV. A
Laser Aperture at distal end of fiber
(FRONT VIEW)
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-01 REV. A
GENERAL INFORMATION 1-5
THIS PAGE IS INTENTIONALLY LEFT BLANK
GENERAL INFORMATION 1-6
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-00 REV. A
2.0
INSTALLATION
2.1
INTRODUCTION
WARNING: Installation by untrained persons is a potential hazard to the persons doing the installations, others present, and to the equipment itself. In addition, improper installation is a potential hazard to the user, persons present during use, and patient.
These installation instructions are provided for use by Lumenis Service Engineers who have completed certification service training on the VersaPulse® PowerSuiteTM Holmium 20 Watt laser.
2.1.1
1.
Site Inspection
Check for proper site set up. This includes proper AC service and adequate space for the console.
AC power configuration: The VersaPulse PowerSuite Holmium 20 Watt requires 110 VAC ±10%, 50/60 Hz, 15 Amps or 220 VAC±10%, 50/60 Hz, 10 Amps single phase electrical service. The power cord is a 15 ft. cable with two conductors and a ground. An AC Controller Sense PCB detects the line voltage and automatically makes the necessary line conditioning adjustments in order for the system to operate. The system can be hard wired to the electrical service or installed to the electrical service with a plug and receptacle. Customers are responsible for supplying electrical connections (i.e., electrical receptacle and mating plug).
Console dimensions and weight: The console measures 24" L x 19" W x 45" H. It weighs approximately 185 lbs. A minimum of 18" of air space is required around the unit to provide adequate cooling air circulation.
The system requires approximately 1.0 gallon (3.79 Liters) of distilled water for its closed loop cooling system. The coolant must be added as described in this procedure.
Complete specifications for the VersaPulse PowerSuite Holmium 20 Watt laser are included later in this section and in the Lumenis VersaPulse PowerSuite Holmium 20 Watt laser Operator Manual. Contact Lumenis Technical Support in Santa Clara, CA. if there are any questions concerning site preparation.
2.
Verify the AC mains voltage at the site.
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-02 REV. A
INSTALLATION 2-1
Frequency: Voltage: Current: Phase:
50/60Hz 110 VAC ±10% 15A Single ()
220 VAC ±10% 10A
2.1.2
1.
Unpack & Inspect Laser
Check the crate/carton for any shipping damage.
The shipper is responsible for any damage to the system in shipment. If the crate/carton appears to be damaged, report the damage to the customer and shipper.
2.
Remove the console and accessories from the crate (refer to Fig. 2.1).
(TBD)
FIG. 2.1: SHIPPING CRATE
3.
Move the system to its installation location.
The VersaPulse PowerSuite Holmium 20 Watt laser rolls best when pushed from the rear handle. The front wheels swivel, the rear wheels do not.
4.
Open/remove covers and do a visual inspection of the interior.
Refer to Section 5 for information on removing the covers. Open the front cover, then remove the top and two side covers. Inspect the interior carefully for loose or broken electrical or optical connections, loose or broken plumbing connections, or any indication of shipping damage.
5.
Record the mains voltage on the Certification Report.
6.
Connect to AC service.
CAUTION: Once connected to the site electrical service, lethal voltages are present inside the unit. The AC power is present at the circuit breaker, main contactor and the AC Controller Sense PCB. Review and understand the safety subtopic in Section 5 before proceeding.
The system can be hard wired to electrical service, but is more typically connected by a plug to an electrical outlet. INSTALLATION 2-2 VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-02 REV. A
If the system is to be hard wired, the customer must provide an electrician to wire the cord end into the electrical service outlet. A lockable electrical service disconnect switch must be installed if the system is hard wired.
If the system is to be plugged into an electrical receptacle, the appropriate receptacle should already be installed by the customer's electrician. The installing engineer connects the plug to the end of the VersaPulse PowerSuite Holmium 20 Watt laser electrical cable.
2.1.3
Add Coolant
Add coolant (distilled water) to the fill reservoir. The coolant will drain out of the fill reservoir and into the main reservoir. The system uses approximately 1.0 gallon (3.79 Liters) of coolant. Most coolant can be added at this time until the fill reservoir level stays up. The system coolant level will be "topped off" after the system is turned on (in a later step).
NOTE: Use distilled/deionized water only! Do not use alcohol or glycol based additives.
2.1.4
Turn On
CAUTION:
· Once the circuit breaker is turned on and power is applied to the VersaPulse PowerSuite laser, wait a few minutes and observe for any indication of failure of the mains or turn-on components. Check for any coolant leaks.
· The system will fire during the turn-on sequence regardless if SW4 (Autocal) on the CPU PCB is left or right and the BRH plug is installed. Only those persons required should be present during this portion of the installation - those present must wear appropriate laser safety eye wear and follow all laser safety precautions.
· The cooling fan blades are not covered. The fan is located on the rear of the VersaPulse PowerSuite Holmium 20 Watt laser. It operates whenever the system is turned on. Keep tools, system parts and body parts clear of the fan blades.
1.
Turn and hold the keyswitch to the START position, then after approximately two seconds, release it to the ON position. The system will go through its start up sequence. Observe for normal start up, and for any indication of leaks in the cooling system.
2.
Add additional coolant if necessary.
NOTE: Only add water if disconnected from AC mains. VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-02 REV. A INSTALLATION 2-3
Turn system off and disconnect from the AC mains. Top off the fill reservoir. Reconnect to AC mains and cycle the machine off and on several times, adding coolant as necessary until the fill reservoir level stays up to approximately half full as the system runs.
3.
Perform Fiber Alignment Test, Verify Calibration procedure and the Operational & Safety checks in Section 3.
4.
Replace all covers and prepare the system for demonstration to the customer.
2.1.5
1.
Customer Demonstration
Demonstrate the system operation to the customer.
2.
Fill out and mail the "self mailer" installation quality audit report (for U.S. Field Service).
3.
Fill out the System Certification report.
2.2
PRODUCT SPECIFICATION
Specifications are subject to change without notice.
Classification:
US FDA CDRH laser classification: European EN 60825 laser classification:
Class IV Class 4
Treatment Laser:
Laser Medium Wavelength Pulse Energy Repetition Rate Pulse Width Maximum Power
Solid State 2.1µm (2100 nm) 0.5 - 2.5 Joules per pulse, adjustable in variable increments 5 - 20 Hz 600 µS maximum 20 W
Aiming Laser:
INSTALLATION 2-4
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-02 REV. A
Type Wavelength Maximum Power US FDA CDRH laser classification: European EN 60825 laser classification:
Diode 650 nm ±10nm 5 mW maximum, continuous wave Class IIIa Class 3A
Cooling:
Distilled Water Internal water-to-air heat exchanger Cooling air requirements:
1 Gallon (3.79 Liters) Minimum 46 cm (18 in) from walls
Input Power:
Volts/Amps Frequency Phase Power cord length
110 ±10% VAC @15A 220 ±10% VAC @ 10A 50/60 Hz Single Three conductor: 2 hot, 1 earth ground 15 feet (4.6 meters), 14 AWG
Dimensions:
Height Width Length Weight
45" (114 cm) 19" (48 cm) 24" (61 cm) 185 lbs. (84 kg)
Footswitch Cable Length:
9.5 ft. (2.9 meters)
Environmental:
Operational:
Max. Altitude Temperature Humidity
3,050 m (10,000 ft.) 10 - 30º C (50º F to 86º F) must be above dew point 90% to 27º C (81º F) non-condensing
Non-operational:
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-02 REV. A
INSTALLATION 2-5
Temperature Humidity
0 - 50º C (32º F to 122º F) - must be above dew point 90% at 55º C (131º F), non-condensing
Delivery System:
The laser is intended for use only with Lumenis-qualified delivery systems. Contact your local Lumenis representative for a list of available products.
Laser Safety Eyewear:
The following laser safety eyewear complies with ANSI (American National Standards Institute) and EN207 standards, as noted in the laser safety section of this manual.
INSTALLATION 2-6
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-02 REV. A
3.0 CALIBRATION, ADJUSTMENT & ALIGNMENT
3.1
INTRODUCTION
3.1.1
Overview
This section contains procedures for the checks and adjustments required to maintain the Lumenis VersaPulse® PowerSuiteTM Holmium 20 Watt Laser. The procedures assume the reader has successfully completed a Lumenis service training course on the VersaPulse PowerSuite Holmium 20 Watt laser. Service performed by untrained or unqualified persons can be a hazard to the person or persons doing the service and to others present during the servicing. An improperly serviced medical system can be a hazard to the equipment user, to others present during use, and to the patient upon whom the laser is used.
The procedures should be performed in the order presented, from beginning to end. If only a portion of the procedures are done, the servicing engineer must consider the possible effect of doing just that portion of the procedures (i.e., there may be adjustments done earlier or later in the procedures that impact or are impacted by the portion performed).
Optical Alignment, Topic 3.2, this is performed when the System Check out procedure indicates a problem, any of the various optical/electro-optical/servo components have been adjusted/replaced or the system cannot meet specifications during the various calibration procedures.
Electrical Adjustments, Topic 3.3, verifies the Fan Speed Controller PCB is properly adjusted for optimal cooling and the speaker volume is properly adjusted. This section also includes an energy calibration procedure, which calibrates the voltage output of the two energy monitor circuits to the Field Service Engineer's calibrated power meter.
Operational and Safety Check, Topic 3.4, is an operational check of the system. It confirms that the system turns on properly, responds properly to operator inputs, delivers the multiplexed Holmium beams into the center of an attached fiber, and provides an adjustable aiming beam through the fiber. It also confirms that the proper fault messages are displayed when various connectors (i.e., footswitch and remote interlock plug) are disconnected and the system is prevented from firing.
Periodic Maintenance, Topic 3.5, provides information on periodic maintenance checks to ensure optimum performance of the system.
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
CAL, ADJUST, ALIGN 3-1
3.1.2
Safety Precautions
Lethal voltages and laser emission are the primary dangers to the servicing engineer. In addition to the general safety precautions which always apply when working on electronics and lasers, the servicing engineer must be aware of the following specific precautions:
· Only Lumenis certified VersaPulse PowerSuite Holmium 20 Watt laser service engineers should attempt any service on this system.
· Even with the keyswitch and the breaker in the "OFF" position there are lethal voltages present inside the console. Always disconnect the main electrical service before working on the console.
· Storage capacitors inside the system are capable of holding a lethal charge, even after power has been removed from the unit. A charge level indicator LED located on the B+ Indicator PCB flashes at a rate proportional to the level of charge on the main charging capacitor. The LED can be seen through the small holes on the High Voltage Power Supply cover behind the front door. Do not rely on this indicator to determine that the main charging capacitor has been discharged. Before contacting the main charging capacitor, disconnect the system from the primary power.
· Do not touch the Ho:YAG Cavity Module when the system is on - IT IS A SHOCK HAZARD. The Ho:YAG Cavity Module is electrically isolated from the chassis and can be at a voltage potential much higher than ground. A Neon lamp on the Starter Indicator PCB indicates lamp start high voltage is present when flashing. B+ is always on the pod's terminal block. The B+ voltage can be measured with respect to chassis ground.
· Ho:YAG laser emission is invisible to the human eye. Because the Ho:YAG laser energy can not be seen, there is no visible indication of the primary or reflected beam. Eye protection that attenuates the Holmium wavelengths to a safe level must be worn by all persons in the area of the laser system, whenever the laser is being serviced.
· The Ho:YAG laser light and its reflections are potential burn hazards and can ignite flammable materials. Use extreme caution when operating the system with covers opened or removed. The covers contain the beam and reflections safely within the console. Only those persons required should be present during servicing and eye protection that safely attenuates the Holmium wavelengths must be worn by all present.
· The Ho:YAG laser light and its reflections are potential hazards to the eye and skin. Use extreme caution when operating the system with the covers opened or removed. The covers contain the beam and reflections safely within console. Only those persons required should be present during servicing and eye protection that safely attenuates the Holmium wavelengths should be worn by all those present.
3.2
OPTICAL ALIGNMENT
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
CAL, ADJUST, ALIGN 3-2
Perform the Optical Alignment procedures whenever any optical or electro-mechanical devices have been replaced or adjusted in the optics bench or in the laser head. Note that the procedures should be performed in the order presented, from beginning to end. If only a portion of the procedures are done, the servicing engineer must consider the possible effect of doing just that portion of the procedures (i.e., there may be adjustments done earlier or later in the procedures that impact or are impacted by the portion performed).
3.2.1
Resonator Alignment
Required Special Tools:
Laser Safety Eyewear (glasses) Laser Safety Eyewear (goggles) FieldMaster Power Meter (from CAG) LM-150FS Detector Head (from CAG) Alignment Tool, Resonator Laser Footprint Paper Polyethylene Bags Lens Tissue Reagent Grade Methanol
0638-429-01 0638-430-01
0640-822-51 3207-0091 3804-0065
1.
Remove the AC power cord from the AC power source and remove the necessary optics covers.
2.
Replace, clean and inspect all optical surfaces as required.
3.
Remove the fiber focus assembly and install the alignment tool (P/N 0640-822-51).
Be sure the cross hair is out of the beam path.
4.
Disable Autocal (SW2 down), block the resonator and turn the system on. Set the system into SERVICE MODE by moving SW1 on the Controller PCB and set the following operating parameters:
Rate Lamp Energy
5Hz 50 J
5.
Remove block from resonator, then place the system into READY.
6.
Fire the laser and adjust the HR until the resonator is lasing.
7.
Reduce the Lamp Energy to 30 J.
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
CAL, ADJUST, ALIGN 3-3
8.
Take burns after the alignment tool and adjust the HR for the best mode.
Mode specification: A "bulls eye" pattern with at least three distinct rings in addition to the central ring must be visible.
9.
Flip the cross hair into the beam and take burns after the alignment tool.
Adjust the OC to center the beam on the cross hair.
10. Repeat steps 8 and 9 until the beam is centered and the mode is in specification.
11. Tighten the lock nuts on the HR and OC.
Verify that the beam is still centered and the mode is in specification.
12. Place the laser is STANDBY mode.
Remove the alignment tool from the beam path and position the detector head in the beam path.
13. Set the system to the following operating parameters:
Rate Lamp Energy
12 Hz 75 J
Place the system into READY
14. Fire the laser and record the maximum power.
Maximum Power Specification: > 25 Watts
Measured Power = ________________ Watts
15. Re-install the fiber focus assembly and the resonator cover.
16. Perform the Fiber Focus Alignment procedure.
CAL, ADJUST, ALIGN 3-4
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
3.2.2
Fiber Focus Alignment
Required Special Tools:
Laser Safety Eyewear (glasses) Laser Safety Eyewear (goggles) Transimpedance Detector Kit Oscilloscope Service Attenuator Optic Assembly Fiber Port Alignment Tool Test Fiber Red Permanent Marker Inspection Microscope
0638-429-01 0638-430-01 0614-868-51 0641-226-51 0641-236-51 0621-675-01 0623-171-51
1.
Remove fiber nut plate from SMA threads and install Fiber Port Alignment Tool (0641-236-51) to the focus assembly wall. Loosen SMA plate screws (x3) slightly, then clamp alignment tool set screw to SMA plate.
2.
Install Service Attenuator Optic Assembly (0641-226-51) on shutter blade, then install Transimpedance Detector (0614-868-51) on SMA threads. Connect detector amp to oscilloscope.
3.
Disable Autocal (SW2 down), block resonator, and turn laser on. Go to service mode, and open shutter.
4.
Remove block from resonator and fire laser at 10Hz, 50J pump energy. Set oscilloscope to 1V/DIV with sweep time of 50 microseconds, positive trigger. Adjust scope to capture pulse.
5.
Use fixture adjustment screws to "push" the SMA plate left/right and up/down to peak the signal on the detector. Tighten the SMA plate screws (x3).
6.
Remove Service Attenuator Optic Assembly from shutter and connect an "inked" burn test fiber to the fiber port. Fire a few shots on the fiber (at 50J) and use microscope to inspect burn pattern.
7.
If burn is well centered, remove Fiber Port Alignment Tool and reinstall fiber nut plate. Otherwise, repeat alignment on detector until signal is better peaked.
3.2.3
1.
Pyro Detector Alignment
Connect the oscilloscope probes to TP4 (MAIN), TP1 (SAFETY), and Ground on the Pyro PCB or TP6 (MAIN), TP7 (SAFETY) and Ground on the Controller PCB.
NOTE: Be sure to attach the ground lead to the ground test point. VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A CAL, ADJUST, ALIGN 3-5
2.
Disable the safety shutter.
NOTE: By disabling the shutter, the shutter will remain closed.
3.
Set the laser parameters to 10 Hz, 40 J and place the laser in READY mode.
4.
Fire the laser and sweep both the X and Y pyro imaging mirror adjustment screws to find the center of travel. Be sure both energy signals are peaked on the oscilloscope.
5.
Lock down both the X & Y lock nuts, and remove the oscilloscope probes.
3.2.4
1.
Aiming Laser Alignment
Attach the power calibration fiber (P/N 0623-973-01) to the fiber port.
2.
Sweep both X and Y diode laser mount adjustment screws to get the optimal beam output out of the fiber.
The optimal beam should have a bright center, and the beam should not exhibit a halo (outer ring) or a donut (dark center).
A C C EP TA BLE (Id ea l)
U N A C C EP TA BLE (Br ig h t H a lo )
U N A C C EP TA BLE (A im in g Bea m is o u t o f A lig n m en t)
FIG. 3.1: AIMING BEAM PROFILE
CAL, ADJUST, ALIGN 3-6
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
3.3
ELECTRICAL ADJUSTMENTS
The following procedures calibrate the energy out of the VersaPulse PowerSuite Holmium 20 Watt laser system. It sets the Pre-Amp gain stage and the Integrator Amp gain stage as addressed in Subtopic 3.3.1.1 and 3.3.1.2. The following test equipment is required for calibrating the system:
Oscilloscope External Power Meter Test Laser Fiber Digital Voltmeter (DVM)
0623-973-01
3.3.1
Energy Calibration
The following procedure prepares the VersaPulse Power Suite Holmium 20 Watt laser for calibration.
WARNING: Energy calibration is a procedure to be performed only by Lumenis -certified service engineers or customers who have taken and passed a Lumenis Service Certification course. Adjustment by anyone other than a trained Lumenis service engineer or a certified customer voids any existing manufacturer's warranty on the equipment. Possession of this manual and/or service tools does not authorize repair or modification of Lumenis equipment by uncertified personnel.
1.
Turn the laser on and access the SERVICE MODE by flipping the service switch (SW1) on the Controller PCB.
2.
Attach the test laser fiber and set up the external power meter.
3.
Set the Rep Rate to 10Hz and place the laser in READY mode.
3.3.1.1 Pyro Pre-Amplifier Gain Adjustment
1. Depress the footswitch and adjust the LAMP ENERGY in increments of 5 Joules until a value of 6 ±0.25 Watts are measured out of the fiber on the external power meter.
2.
Set the shutter to closed, attach an oscilloscope probe to TP6 (MFDIF) and Ground on the Controller PCB and set the oscilloscope to 1V/div, auto trigger.
3.
Depress the footswitch and adjust the potentiometer R1 (MGAIN) on the Pyro PCB until a peak of 4.0 ±0.1V is measured on the oscilloscope. CAL, ADJUST, ALIGN 3-7
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
4.
Move the oscilloscope probe to TP7 (SFDIF) on the Controller PCB.
5.
Depress the footswitch and adjust the potentiometer R2 (SGAIN) on the Pyro PCB until a peak of 4.0 ±0.1V is measured on the oscilloscope.
3.3.1.2 Integrator Amplifier Gain Adjustment
1. Set the shutter to normal, depress the footswitch and adjust the LAMP ENERGY to obtain 10 Watts of delivered power out of the fiber (PULSE RATE @ 10 Hz).
2.
Set the shutter to closed, attach the oscilloscope to GND and TP5 (MERG) on the Controller PCB.
NOTE: You can also use a DVM to monitor the signals by attaching the DVM leads to TP24 and GND.
3.
Depress the footswitch and adjust the potentiometer R3 (MGAIN0) on the Controller PCB until 2.0 ±0.02 V is measured across GND and TP5 (or TP24 if using a DVM).
NOTE: 2V = 1J/Pulse
4.
Move the oscilloscope ground lead to TP10 on the Controller PCB.
NOTE: If using a DVM, move the negative lead to TP20.
5.
Depress the footswitch and adjust the potentiometer R17 (SGAIN0) on the Controller PCB until 0.00 ±0.02 V is measured across TP5 and TP10 (TP20 using a DVM).
6.
Push the READY button and then the CALIBRATE button. (Hold the "CALIBRATE" button until the laser fires by itself).
7.
Access USER MODE by flipping the service switch (SW1) on the Controller PCB or the USER button on the screen.
8.
Verify all rep rates and energy combinations deliver the requested energies ±10%.
9.
Verify Autocal (SW2) is enabled.
NOTE: Up = Enabled CAL, ADJUST, ALIGN 3-8 VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
10. Turn off the system and back on again. Verify that no error codes/messages appear on the screen.
3.4
OPERATIONAL AND SAFETY CHECKS
CIRCUIT BREAKER AND KEYSWITCH CHECK:
1.
Insert the key into the keyswitch, rotate it to each position and verify that the key can only be removed in the OFF position.
2.
Turn the circuit breaker ON and verify that the switch stays in the UP position.
3.
Rotate the key to the START position, hold for two seconds and release the key.
Verify that the laser turns on and the key automatically returns to the ON position.
4.
Turn the key to the OFF position and verify that the laser shuts off.
5.
Turn the laser back on and turn the circuit breaker off.
Verify that the laser shuts off.
EMERGENCY OFF SWITCH CHECK:
1.
Press the Emergency Stop Switch and rotate the key to the START position.
Verify that the laser does not turn on, then release the E-Stop switch.
2.
Turn the laser ON.
3.
Press the Emergency Stop Switch and verify that the laser shuts off.
FLOW SWITCH CHECK:
1.
Verify the laser remains OFF, disconnect the cable from J12 on the Controller PCB and place an ohmmeter across pins 1 & 2 of J12.
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CAL, ADJUST, ALIGN 3-9
2.
Verify an "Open Circuit" condition ( ohms).
3.
Turn the laser ON.
4.
Verify a "Closed Circuit" condition (<1 ohm), then turn the laser off.
5.
Replace the cable in J12
INTERLOCK CONNECTION CHECK:
1.
Turn the laser ON.
2.
Locate and remove the remote interlock plug at the rear panel.
3.
Verify that the display panel indicates F431 or shows the interlock icon.
4.
Replace the remote interlock plug.
FOOTSWITCH CHECK:
1.
Turn the laser OFF.
2.
Depress and hold the footswitch and turn the laser ON. At the main screen, press READY.
Verify that F401 or "REALEASE FOOTSWITCH" message is displayed. Release the footswitch and turn the laser OFF.
3.
Release the footswitch.
Verify that no footswitch fault messages appear.
4.
Disconnect the footswitch and verify the display indicates F404 or shows the footswitch icon.
5.
Reconnect the footswitch.
CONTROL PANEL CHECK:
CAL, ADJUST, ALIGN 3-10
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
1.
Turn the laser ON and verify that the entire screen is illuminated (backlight working).
Verify that the proper icons are displayed.
2.
Touch each button on the LCD display and verify that the LCD display responds accordingly.
Enter and exit all menu and sub-menu screens.
3.
Switch the laser to SERVICE MODE and repeat step 2 with all service buttons.
AIMING BEAM QUALITY CHECK:
1.
Turn the laser ON and locate a power calibration fiber (P/N 0623-973-01).
Verify the integrity of both the proximal and distal ends of the fiber.
2.
Attach the fiber to the SMA port and turn the aiming beam ON.
Verify that the beam shape does not have a halo or does not look like a donut.
3.
Vary the intensity of the aiming beam using the LCD display controls to distinguish each of the following steps:
OFF LO MED HI
4.
Select the BLINK mode and verify the aiming beam blinks ( 2 Hz).
5.
Return to STEADY mode and disconnect the fiber.
FIBER ALIGNMENT CHECK:
1.
Turn the laser ON and enter into SERVICE mode.
2.
Locate the ink/burn test fiber (P/N 0621-675-01) and verify the integrity of the proximal end of the fiber.
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
CAL, ADJUST, ALIGN 3-11
3.
Apply a small amount of red permanent ink to the fiber end face and verify the complete coverage by inspecting under a microscope.
4.
Enter the "centration" menu and set the following parameters:
a. Shots = 5
b. Lamp Energy = 50 Joules
c. Rate = 5 Hz
d. Mode = READY
5.
Attach the fiber to the SMA port and depress the footswitch.
6.
Remove the fiber and inspect the fiber end face under a microscope.
Verify that the burn is centered within the fiber core. (Refer to Fig. 3.2)..
Cladding Core Footprint
ACCEPTABLE
NOT ACCEPTABLE
NOT ACCEPTABLE
Examining the test fiber end with the 100x microscope - The footprint will not always be circular, but it should be approximately centered in the fiber and away from contact with the cladding.
FIG. 3.2
CALIBRATION CHECK CAL, ADJUST, ALIGN 3-12 VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
1.
Set up a calibrated FieldMaster® with an LM-150FS detector head.
NOTE: An equivalent external power measurement equipment is acceptable.
2.
Turn the laser ON with AUTO-CALIBRATION enabled. Remain in USER Mode.
3.
Locate a power calibration fiber (P/N 0623-973-01) and verify the integrity of both the proximal and distal ends of the fiber.
4.
Attach the fiber to the SMA port and turn on the aiming beam.
5.
Direct the aiming beam to the center of the detector head.
Adjust the distance between the fiber end and the detector surface to achieve a 1 cm spot size.
6.
Place the laser in READY mode.
7.
Fire the laser at each operating point (energy & rate combination) and verify the delivered power (as measured by the FieldMaster) is within ±10% of the requested power.
8.
Disconnect the fiber.
FLASHLAMP CALIBRATION VALUE:
1.
Enable AUTO-CALIBRATION, turn the laser ON and enter into SERVICE MODE.
2.
Go to the calibration screen to view the flash lamp calibration value.
NOTE:
· On new systems (less than 3 months from date of manufacture) the following values must be seen.
0.5J (lo) 2.0J 2.5 (hi)
< 45J < 80J < 90J CAL, ADJUST, ALIGN 3-13
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
· On used systems (age greater than 3 but less than 12 months from date of manufacture) the value must at the following:
High lamp Joules < 110J. · On Service Contract systems, repair if the maximum lamp Joules 115J. If out of warranty and no service contract, owner to pay for repairs before establishing a service contract with Lumenis.
3.5
PERIODIC MAINTENANCE
The VersaPulse Power Suite Holmium 20 Watt laser system requires periodic maintenance on a routine basis in order for the system to perform at original factory specifications. Perform the following maintenance annually or more often as required:
CLEAN INTERIOR AND EXTERIOR
PERFORM A VISUAL INSPECTION
1.
Remove the covers and check for the following:
· Loose hardware
· Broken pieces
· Missing parts
· Abnormal wear
· Water stains
· Cuts or frays in electrical wiring
· Contaminated optics
2.
Replace the particle filter.
3. Replace the DI cartridge. CAL, ADJUST, ALIGN 3-14
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
4.
Tighten all hose clamps
5.
Check the coolant level.
Top off as required with distilled or de-ionized water
6.
Check/replace blastshield optic.
7.
Perform the Operational and Safety Checks.
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CAL, ADJUST, ALIGN 3-15
THIS PAGE IS INTENTIONALLY LEFT BLANK
CAL, ADJUST, ALIGN 3-16
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-03 REV. A
4.0 THEORY OF OPERATION
4.1
INTRODUCTION
4.1.1
Operational Overview
The VersaPulse® PowerSuiteTM Holmium 20 Watt laser system is designed for use in multi-specialty surgical applications. The treatment laser delivers a pulsed 2120nm wavelength energy (invisible) through a user attached delivery fiber in response to the depression of an attached footswitch. The pulses continue until the footswitch is released. A diode laser provides a visible (red, 650 nm) aiming beam. An equipment description, specifications and detailed user operating instructions are included in the VersaPulse PowerSuite Holmium 20 Watt Operator Manual.
A key is required to turn the system on. At turn-on the system undergoes a series of self tests (approximately 60 seconds), then, if no malfunctions are detected during the self tests, goes to its STANDBY condition. If the self testing process detects any malfunction, an error message or fault code will be displayed and the system will not be enabled until the fault condition clears.
Once the unit is in STANDBY the user selects the desired operating parameters through an LCD color display. Controls include aiming beam intensity, pulse energy, and pulse rate. Selections are displayed on the LCD color display.
Aiming beam intensity can be turned off or adjusted for high, low or medium.
Pulse energy and pulse rate combine to determine the average power.
(ENERGY/PULSE)*(PULSES/SECOND) = Average Power in Watts
Holmium:
Pulse energy is adjustable in increments from 0.5 to 2.5 Joules. Pulse rate is adjustable in increments from 5 to 20 Hz. The combination of pulse energy and pulse rate define an operating point. Not all combinations of pulse energy and pulse rate are valid. Consult the Operator Manual for detailed information on the operating points.
A total energy display with a clear function allows the user to keep track of the total energy used from the last time the display was cleared. VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-04 REV. A THEORY OF OPERATION 4-1
A delivery system fiber is attached to a fiber port on the front of the system console. The delivery fiber comes in a number of styles to meet the requirements of various applications (angled, etc.). The system will not fire without a delivery fiber attached.
Once the system operating parameters are selected, the user selects the READY mode, positions the fiber output at the treatment site, then depresses the footswitch to deliver treatment pulses at the rate and energy selected. The treatment delivery will continue until the footswitch is released. The shutter opens and treatment delivery begins without delay.
Fault monitoring continues for as long as the system is turned on, and any detected fault is reported on the LCD color display.
An emergency off button is located on the console next to the key switch. Depressing it will turn the system off. The system may also be turned off by moving the key to the off position or by turning the main breaker off.
NOTE: The "OFF" position is illustrated by this icon
4.1.2
Functional Overview
The VersaPulse Powersuite Holmium 20 Watt consists of only one Ho:YAG rod.
Refer to the VersaPulse PowerSuite Holmium 20 Watt Block Diagram in Section 8 page 8-3. The Ho:YAG cavity includes a rod, flash lamp, high reflector and an output coupler.
The Holmium 20 Watt laser contains the following:
· Flash lamp supply switching - The VersaPulse PowerSuite Holmium 20 Watt uses a combination of capacitor storage and rectified AC voltage to supply the current required to turn on the flash lamp. The lamp current, pulse width, and voltage level of the charge on the capacitor determines the amount of light energy out of the lamp, and therefore, the pulse energy out of the rod. The VersaPulse PowerSuite Holmium 20 Watt laser uses Isolated Gated Bipolar Transistors (IGBT) to switch the reservoir capacitor bank voltage through the flashlamp.
· Control - The VersaPulse PowerSuite Holmium 20 Watt laser uses a Hitachi RISC based HD64F705 microprocessor.
For the purposes of this discussion, the VersaPulse PowerSuite Holmium 20 Watt laser is divided into the following functional subsystems. The remaining topics in this section provide a detailed description of each subsystem.
Power Switching, Conditioning, Distribution (4.2) - Provides switching and conditioning of the primary power input, converts the AC line voltage to DC voltages used within the system and distributes the various voltages throughout. It includes the turn-on and turn-off circuitry. It does not include the high voltage power supply. THEORY OF OPERATION VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 4-2 0640-665-04 REV. A
Cooling (4.3) - The cooling system removes heat from the Ho:YAG cavity. It is a closed loop distilled water system including a pump, reservoir tank, fill tank, heat exchanger, variable speed fan, D/I filter, particle filter, flow switch, temperature sensor and a conductivity sensor.
Control Electronics (4.4) - The control electronics executes the software instructions to provide overall control to the VersaPulse PowerSuite Holmium 20 Watt laser. It includes a microprocessor, a Flash PROM, Erasable Programmable Logic and its associated circuits (DIO, ADC, DAC), LCD color display, and a number of electronic and electro-mechanical devices.
Flash Lamp Supply Circuits (4.5) - The flash lamp supply starts and simmers the flash lamp, responds to control electronics commands to charge the capacitor bank and discharge the capacitor bank through the flash lamp. It includes the capacitor bank, IGBT driver circuitry, flash lamp select IGBT's, starter transformer, flash lamp and simmer/start controller. The flash lamp is simmered at a low current 150mA between flashes (flash lamp is kept on in order to allow instantaneous IGBT turn on). The simmer circuitry provides the simmer current to the flash lamp and a transformer is used to generate a starter pulse to ionize the flash lamp.
The Ho:YAG pulses of laser energy are controlled by command signals from the control electronics. Prior to each pulse the control electronics send a set of parameters to the HVPS. The parameters will set the following:
· Lamp volts
· Lamp current/energy
· Pulse width
The HVPS will then charge the capacitor bank to the indicated voltage. To get a pulse of treatment energy the control electronics triggers the IGBT. The IGBT turn-on creates a current path for the capacitor bank through the flash lamp.
Optics (4.6) - The optics include the portions of the system that operate on the Ho:YAG beam and/or diode aiming beam. The rest of the beam path includes the following optical components.
Wedge Optic - A wedge optic is required to monitor the power. Two samples are reflected off the wedge. An imaging mirror directs the sample toward two pyrodetectors mounted on the Pyro PCB (TP5 & 2). The pyro circuitry translates the energy sample current into a voltage proportional to the energy of the YAG pulse.
Safety Shutter - Blocks the treatment beam path when de-energized.
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-04 REV. A
THEORY OF OPERATION 4-3
If the laser is fired with safety shutter closed (during autocal), all energy is directed into the beam dump.
Aiming Beam Diode, Folding Mirror, and Combiner Optic - Aiming beam is provided by a 650 nm diode laser. The user can select high, low, or medium intensity; or turn the aiming beam off. The diode mount is adjusted to place the aiming beam coaxial with treatment beam.
Fiber Focus Lens - Focuses the beam into the end of the fiber to approximately 260µm diameter spot.
Blast Shield - Protects the fiber focus lens from debris ejected from the proximal end of the fiber in the event of a fiber failure.
Delivery Fiber - A number of delivery fibers are available for use with the VersaPulse PowerSuite, each providing features suiting it to certain applications, such as orthopedic, endoscope, laparoscope, laser assisted disk surgery, etc. Most fibers are designed for a single use and are not reusable.
Software (4.7) - Software instructions are provided for the microprocessor to operate the system in response to user inputs. It also provides instructions for the firmware (i.e., EPLDs) in the monitoring and responding to any potential unsafe condition. The software is stored in a Flash PROM and in the EPLDs on the Controller PCB. Software upgrades can be accomplished by replacing the software Flash PROM and/or reprogramming the EPLDs.
4.2
POWER SWITCHING, CONDITIONING, DISTRIBUTION
Refer to schematic 8-4, 8-5 & 8-6 in Section 8.
The power switching, conditioning and distribution section of this system contains a number of components to perform the following functions:
· Switch and filter mains power
· Detects mains voltage
· Energize a low voltage interlock loop
· Soft start the main isolation transformer
· Distribute alternating current to various loads
THEORY OF OPERATION 4-4
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-04 REV. A
The primary components of the system are the current circuit breaker, the AC Control PCB and the Voltage Sense PCB. The description of the components and their functions are described in the following sub-sections. Refer to Section 8, AC Control PCB schematic.
4.2.1
Mains Input Power
The VersaPulse PowerSuite Holmium 20 Watt laser operates off of 110 VAC ±10% @16 Amps 50/60 Hz or 220 VAC ±10% @ 10A 50/60 Hz line voltage. The main circuit breaker is rated at 20 Amps. The mains power is brought into the system from a specifically rated "Hospital Grade" plug through a 15 foot (4.5 meter) long 3-conductor, 14 AWG cord. Two hot conductors are connected to the input of the circuit breaker, and the third conductor, earth ground, is connected to the system chassis. Power is switched through a 16 Amp circuit breaker to a line filter and to the terminal block, TB1 on the AC Control PCB. The circuit breaker is the primary power switch. For systems connected to 220VAC, a 10 Amp time lag fuse (F13) protects the system from an over current condition.
4.2.2
Power Distribution
All power from the main isolation transformer secondary is directed in parallel through the fuses (except to the high voltage power supply), then to the individual loads (refer to Subtopic 4.2.2.5).
4.2.2.1 AC Control Board
The AC Control PCB contains surge protection circuitry, a low voltage power supply module, the interlock circuit, soft start resistors, a soft start relay, two voltage tap relays, transformer secondary side fusing to the loads, and an isolated low voltage power supply.
Mains power enters the AC Control PCB at TB1. At J49, the two surge protectors are connected across the mains and in series with a spark gap to earth ground.
NOTE: Remove the surge protection devices by disconnecting J49 if performing high potential (hi-pot) tests.
Once past the surge protection, mains voltage is directed through the soft start resistors, R3 and R4, to terminal block TB2, to the soft start and voltage tap relays, as well as to the low voltage power supply module, PS1 and to the voltage sense transformer T1. The low voltage power supply module PS1 generates +24 VDC to power the Voltage Sense PCB at J50 and the interlock loop.
4.2.2.2 ±15 VDC Isolated Power Supply
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-04 REV. A
THEORY OF OPERATION 4-5
The AC Control PCB contains the circuitry for an isolated ±15 VDC Power Supply. The circuit consists of a fused AC input to a full-wave rectifier BR1, filter capacitors and zener diode limiters at the input of the positive and negative voltage regulators U1 and U2 respectively, and capacitor filtered, fixed voltage output stages. The AC input is connected to J47, and the ±15 VDC Isolated Power Supply output is available at connector J30. Both the input and output of this power supply are not connected to the chassis ground and therefore, is completely electrically isolated from the rest of the system.
4.2.2.3 Voltage Sense PCB
The Voltage Sense PCB, connected to the AC Control PCB at connector J50, is responsible for determining mains line voltage, controlling voltage tapping relays and a soft start relay. Mains voltage is determined in order to energize the correct voltage tapping relay (which connects mains to the main isolation transformer TR1) when the key is turned from OFF to the RUN position. The soft start relay is energized (removing the soft start resistors from the mains path) when the key is turned to the START position. Power to this board is +24VDC, which is supplied by PS1 on the AC Control PCB. A +10VDC reference voltage is made by U4, which supplies Vcc to all circuitry on this board. The mains voltage monitor circuit is sent a small AC signal proportional to the mains voltage through a 700:1 step-down transformer T1 on the AC Control PCB. The AC signal is rectified and filtered, and finally generates a DC level of 3.0 VDC for every 100 Volts of mains voltage out of U7 at TP5. This 3V/100V signal is sent to the amplifier with a gain of one-third, generating a DC level of 1.0 VDC for every 100 Volts of mains voltage at TP6. This signal is then sent to the Controller PCB to be measured by an Analog-to Digital Converter circuit.
The 3V/100V signal is also sent to two window comparator circuits (U5C & U5D). If TP5 is greater than 2.4VDC, the output of U5D will be a high input signal to the D Flip-Flop U3B. If TP5 is greater than 4.5 VDC, the output of U5D and U5C will both output high input signals to the D Flip-Flops (U3B & U3A), respectively. When the D Flip-Flops are clocked, by way of the key turned to the START position and after a short R16/C6 time delay, both inputs to the AND gate U6B are high, causing Q4 to turn on, pulling /230_RELAY_DRIVE_NOT/ signal low, energizing the 230V relay (K5) on the AC Control PCB. If TP5 is greater than 2.4 VDC but less than 4.5 VDC, the output of D Flip-Flop U3B will be high, the /Q/ output of the D Flip-Flop U3A will go high, causing the AND gate U6C to be high and Q2 to turn on, pulling the /115_RELAY_DRIVE_NOT/ signal low, energizing the 115V relay on the AC Control PCB (K4). If the signal at TP5 is less than 2.4 VDC, neither the D-Flip-Flop input will be clocked through and neither voltage select relay will be energized.
Approximately 500 milliseconds after the voltage tap relay is energized by the R18/C8 time delay, the output of U5A drives high, resulting in the output of the AND gate U6A to drive high, turning on Q3, pulling the /SOFT_START_RELAY_DRIVE_NOT/ signal low, energizing the soft start relay on the AC Control PCB (K3). Once K3 is energized, the mains current goes directly through the K3 contacts, bypassing the soft start resistors, R3 and R4, on the AC Control PCB.
4.2.2.4 Interlock Loop
The interlock loop is powered by +24 VDC, the output of PS1, which is protected by fuse (F12). If +24 VDC is present, LED10 will be on. The DC signal is passed off to the Emergency Stop Switch, and if closed, will return +24 VDC and illumine LED9. The DC signal is then sent to the thermostat in the Main Isolation Transformer T1, and if less than 110º THEORY OF OPERATION 4-6 VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-04 REV. A
C, will return +24 VDC and illuminate LED8. The DC signal is then passed on to the keyswitch SW2. When the key is turned from OFF to the RUN position, LED7 illuminates and +24 VDC is sent to the Voltage Sense PCB to preset the voltage selector D Flip-Flops. If the key is turned from the RUN to the START position, SW1 is closed, illuminating LED6, supplying +24 VDC to the Fan PCB and to the control relays, as well as supplying the KEY_24VDC signal to the Voltage Sense PCB to drive the voltage control and soft start relays as well as to the High Voltage Power Supply interlock loop.
In order for the laser to remain on after the key is released from the START position, either the CPU Defeat Jumper must be installed or the CPU Holding Relay must be energized. Normally, the combination of +5 VDC from the Low Voltage Power Supply and the REL- signal from the CPU will energize the CPU Holding Relay.
4.2.2.5 Isolation Transformer
The Isolation Transformer TR1 is a 3KVA toroid with a split (balanced) primary and two secondary outputs, with an internal automatic resetting 110º C thermal fuse (thermostat). The primary side has two 110V windings, which are connected (via voltage select relay) in parallel for 110V operation or in series for 220V operation. The secondary outputs are 220V for the main loads, and 390V for the high voltage power supply.
The loads connected to the isolation transformer secondary consist of the following:
· High Voltage Power Supply (flash lamp drive)
· A water pump
· A Low Voltage Power Supply (control electronics)
· An auxiliary 30W transformer.
All secondary loads are fuse protected.
4.2.3
Turn On
The following sections describe the sequence of events starting from the time the system circuit breaker is turned on to the completion of the self-test routine after the keyswitch is set to the run position.
4.2.3.1 Turn On Sequence
If all necessary components are installed, connected and functional, the turn on sequence is as follows: VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual THEORY OF OPERATION 0640-665-04 REV. A 4-7
a. The circuit breaker is closed.
· Energizing the power supply module PS1 to generate +24 VDC for the voltage select circuitry and the interlock loop.
· Energizes small signal transformer T1 to establishing the mains voltage level for the voltage select comparator circuitry.
b. The key is rotated from the OFF position to the START position, causing the voltage select Flip-Flops to be preset.
c. The key is rotated from the RUN position to the START position.
· +24 VDC to be available to the voltage select and soft start relays
· Sending the KEY_24VDC signal to the voltage select circuitry causing the voltage select relay and soft start relays to energize
· Supplies +24 VDC to the HVPS interlock circuit.
d. The correct voltage select relay is energized, supplying a low current to the isolation transformer T1.
e. The soft start relay is energized, shunting the current around the soft start resistors and supplying full current to the isolation transformer T1.
f. The loads are energized, specifically the low voltage power supply, turning on the control electronics and enabling the CPU Holding relay to be energized.
h. The key is released from the START position and returns to the RUN position.
4.2.3.2 Turn Off
The laser will remain ON until any of the following occur:
a. Mains power is interrupted or lost.
b. The circuit breaker CB1 is opened. THEORY OF OPERATION 4-8 VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-04 REV. A
c. +24 VDC power supply module fuses F8, F9 or F12 fails.
d. The Emergency Stop Switch is pressed.
e. The key is turned to the OFF position.
f. The LVPS fuse F5 fails.
g. A hazardous fault is detected by software de-energizing the CPU Holding Relay K2.
h. Any related electronic component or connection fails.
4.3
COOLING SYSTEM
Refer to the Coolant System Simplified Diagram (Fig 4.x). The purpose of the cooling system is to remove heat generated by the laser system during the normal course of use. The plumbing loop consists of aluminum and stainless metals, reinforced plastic tubing and nylon fittings to prevent contamination and conduction. A positive displacement vane pump circulates the coolant around the loop where heat is added by a flash lamp and High Voltage Power Supply and then is removed in a forced-air liquid-to-air heat exchanger. A de-ionizing cartridge removes conductive contaminants from the coolant and particle filter traps. Any suspended particles (pump vane wear). Sensors monitor coolant temperature to control fan speed. The cooling system loop and the system components are described below.
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THEORY OF OPERATION 4-9
FILL TANK
LASER MANIFO LD
HEAT EX CHANGER
HVPS COLD PLATE
W ATER PUMP
PARTICLE FILTER
FLO W SW ITCH
DRAIN
FIG. 4.1 SIMPLIFIED COOLING DIAGRAM
4.3.1
Coolant
The coolant consists of approximately one gallon (3.79 Liters) of distilled/de-ionized water. Do not mix any solvents or anti-freeze with the coolant, as not all components of the cooling system are solvent compatible. Since the laser contains only water, do not FREEZE! Permanent damage will result if laser is allowed to freeze. THEORY OF OPERATION 4-10 VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-04 REV. A
DI CARTRIDG E
4.3.2
Fill Tank
A 1 quart (1 Liter) molded plastic tank is part of the cooling loop. The tank is the highest point of the loop and is used to fill the cooling system. Coolant circulates through this tank, and the level is generally maintained at one-half of maximum capacity. The cap must be secure to prevent leaks, and the cap must be removed when draining the system.
4.3.3
Heat Exchanger
The heat exchanger is made of single-row aluminum construction. Warm water enters at the top, flows down through the rows under gravity and is picked up by the water pump. A fan blows air across the heat exchanger to remove the heat.
4.3.4
Fan
The variable speed cooling fan is capable of moving 300 CFM across the heat exchanger. The fan is driven by a DC motor which is speed controlled based upon the output temperature of the air exiting the heat exchanger. The speed of the fan increases as the temperature of the air increases. The fan speed control electronics are self contained in the fan.
4.3.5
Pump Head
The pump head, manufactured by PROCON, is a stainless steel, positive displacement graphite vane pump. Coolant is drawn into the pump head by way of gravity feed, and coolant flows out of the pump head at a rate of 3.3 gpm) @ 90 psi (15 lpm @ 63,276 kg/m2). The pump head has a built in, pre-adjusted overpressure relief valve. The pump is mechanically attached to the pump motor by means of a "V-band" clamp. The output side of the pump head is connected to the pump head manifold.
4.3.6
Pump Head Manifold
The pump head manifold is made of plastic and is attached to the output side of the pump head. Connected to the manifold are the conductivity sensor, a plug (spare sensor connection), and a fitting to connect the output hose.
4.3.7
Pump Motor
THEORY OF OPERATION 4-11
VersaPulse® PowerSuiteTM Holmium 20 Watt Service Manual 0640-665-04 REV. A
The motor, made by General Electric, is a 1/3 HP thermally protected AC motor that continuously drives the pump head. The shock-mounted motor is mechanically attached to the pump head by means of a "V-band" clamp. The motor contains sealed shaft bearings and therefore, no service is required.
4.3.8
Flow Switch
A switch is used to monitor the coolant flow. The switch is a pressure activated, magnetic reed spring-loaded float. As water is forced up from the bottom of the switch, the float is pushed back toward the magnetic reed closing the switch. When coolant flow has stopped, the spring returns the float to the open position. The top of the switch can be removed for cleaning and/or inspection. The flow switch electronics are described in the Control Electronics section.
4.3.9
Particle Filter
Installed in the cooling loop is a particle filter housing which contains a replaceable 0.2µm filter cartridge. The purpose of the filter is to trap any suspended particles that are larger than 0.2µm is size. Since the cooling loop is a closed system, the filter should remain clean. Normal pump head wear will make the filter turn from white to black. Brown or green contaminants are generally caused by biological growth. The filter is typically replaced on an annual basis.
4.3.10 Drain
Located on the underside of the system chassis is a quick-connect, self-sealing drain valve that permits the coolant to be drained from the cooling system. A mating connector and drain hose is required to activate the valve. The fill tank cap and laser manifold vent screw must be opened to allow the coolant to drain.
4.3.11 DI Cartridge
Installed in the cooling loop is a replaceable de-ionizing filter cartridge manufactured by IONICS. The filter cartridge is connected in parallel across the high voltage power supply and is flow direction sensitive. The purpose of the filter ca