Metex MXD 4660A free download

File name Precaution.pdf

Precaution 1. Precaution To avoid possible damages or electric shocks or exposure to radiation, follow the instructions below with regard to safety, installation, service and ESD. 1-1 Safety Precautions 1. Make sure all protective devices are properly installed including non-metallic handles and compartment covers when installing or re-installing the chassis or chassis assemblies. Make sure that no gaps exist between the cabinets for children to insert their fingers in to prevent children from receiving electric shocks. 6. Errors may occur when the resistance is below 1.0 or over 5.2 . In these cases, make sure that the device is repaired before sending it back to the customer. 3. Check for Electricity Leakage (Figure 1-1) Warning: Do not use an insulated transformer for checking the leakage. Use only those current leakage testers or mirroring systems that comply with ANSIC 101.1 and the Underwriter Laboratory's specifications (UL1410, 59.7). 5. Warning for Engineering Changes: Never make any changes or additions to the circuit design or the internal part for this product. Ex: Do not add any audio or video accessory connectors. This might cause physical damage. Furthermore, any changes or additions to the original design/engineering will invalidate the warranty. Warning - Hot Chassis: Some TV chassis are directly connected to one end of the AC power cord for electrical reasons. Without insulated transformers, the product can only be repaired safely when the chassis is connected to the earthed end of the AC power source. To make sure the AC power cord is properly connected, follow the instructions below. Use the voltmeter to measure the voltage between the chassis and the earthed ground. If the measurement is over 1.0V, unplug the AC power cord and change the polarity before reinserting it. Measure the voltage between the chassis and the ground again. 7. Some TV chassis are shipped with an additional secondary grounding system. The secondary system is adjacent to the AC power line. These two grounding systems are separated in the circuit using an unbreakable/unchangeable insulation material. When any parts, material or wiring appear overheated or damaged, replace them with new regular ones immediately. When any damage or overheating is detected, correct this immediately and make a regular check of possible errors. 2. DEVICE UNDER TEST TEST ALL EXPOSED METAL SURFACES 2-WIRE CORD ALSO TEST WITH PLUG REVERSED (USING AC ADAPTER PLUG AS REQUIRED) LEAKAGE CURRENT TESTER (READING SHOULD NOT BE ABOVE 0.5mA) 8. EARTH GROUND Fig. 1-1 AC Leakage Test 4. A high voltage is maintained within the specified limits using safety parts, calibration and tolerances. When voltage exceeds the specified limits, check each special part. 9. Check for the original shape of the lead, especially that of the antenna wiring, any sharp edges, the AC power and the high voltage power. Carefully check if the wiring is too tight, incorrectly placed or loose. Never change t