Đang chuẩn bị liên kết để tải về tài liệu:
Ebook Type MVAJ Tripping and Control Relays

Ebook Type MVAJ Tripping and Control Relays presrent of safety section; installing, commissioning and serviecing; equipment operating conditions; older products; decommissioning and disposal; technical specifications. | AREVA Type MVAJ Tripping and Control Relays Service Manual R8015G HANDLING OF ELECTRONIC EQUIPMENT A person s normal movements can easily generate electrostatic potentials of several thousand volts. Discharge of these voltages into semiconductor devices when handling circuits can cause serious damage which often may not be immediately apparent but the reliability of the circuit will have been reduced. The electronic circuits of AREVA T D products are immune to the relevant levels of electrostatic discharge when housed in their cases. Do not expose them to the risk of damage by withdrawing modules unnecessarily. Each module incorporates the highest practicable protection for its semiconductor devices. However if it becomes necessary to withdraw a module the following precautions should be taken to preserve the high reliability and long life for which the equipment has been designed and manufactured. 1. Before removing a module ensure that you are a same electrostatic potential as the equipment by touching the case. 2. Handle the module by its front-plate frame or edges of the printed circuit board. Avoid touching the electronic components printed circuit track or connectors. 3. Do not pass the module to any person without first ensuring that you are both at the same electrostatic potential. Shaking hands achieves equipotential. 4. Place the module on an antistatic surface or on a conducting surface which is at the same potential as yourself. 5. Store or transport the module in a conductive bag. More information on safe working procedures for all electronic equipment can be found in BS5783 and IEC 60147-0F. If you are making measurements on the internal electronic circuitry of an equipment in service it is preferable that you are earthed to the case with a conductive wrist strap. Wrist straps should have a resistance to ground between 500k - 10M ohms. If a wrist strap is not available you should maintain regular contact with the case to prevent the build up of .