Siemens 7SA511 manual Electrostatic Discharge Possible equipment damage

7SA511 Line Protection Relay Chapter 8

8. Maintenance

The 7SA511 relay is designed so that no special testing, calibration, or maintenance is required. All measurement and signal processing circuits are fully solid state and, with the exception of the internal backup battery, require no periodic maintenance. The following basic maintenance procedures are provided in this section

Inspecting the power supply fuse

￿Replacing the backup Erasing stored data

To inspect the power supply fuse or replace the backup battery, the relay’s front cover must be removed and the relay removed from its housing. If required, see Chapter 4 “Installation” for procedures on removing the front cover and removing or replacing relay modules.

DANGER

Hazardous voltages in the equipment. This can cause severe personal injury and equipment damage.

Testing should be performed only by qualified personnel. Follow all safety instructions contained herein. Do not insert or withdraw the module under power. Do not make wiring connections or changes under power.

CAUTION

Electrostatic Discharge

Possible equipment damage.

The relay module contains CMOS circuits. The module must never be withdrawn from or inserted into the housing with power connected.

Electrostatic discharges into or around the uninstalled relay or any of its components must be avoided.

The use of grounding straps or touching a grounded metal surface before handling the uninstalled relay is essential.

July 27, 1995 8-3