Edwards TCU 40/80

7.7.8 Lamp check/replacement
Electric Shock
Ensure all electrical power has been removed and
the main circuit breaker has been turned off due to
the presence of high voltage or current.
Caution
Should a lamp require replacement, notify the
appropriate personnel that an EMO condition will
occur.
Failure to follow these instructions may result in
the shut-down of the process tool and associated
equipment.
Visually verify that the POWER ON and RESET lamps are working. If either lamp needs replacement
and the proper authorization has been obtained:
1. Press STOP.
2. Turn off the main circuit breaker (CB1).
3. Disconnect power cord from mains power supply.
4. Locate the two securing screws on the front electrical panel and loosen . Open the electrical drawer.
5. If replacing the POWER ON lamp, locate contactor block (LPl) on the back side of the front
electrical panel. If replacing the RESET lamp, locate contactor block (PBl) on the back side of the
front electrical panel.
6. Pry up the metal retaining ring attached to the coupling plate. Remove the contact block assembly.
7. Replace the defective lamp.
8. Reinstall the contact block assembly by snapping it back onto the front clement.
9. Close the electrical drawer and tighten securing screws.
10. Reconnect mains power and turn on the main circuit breaker (CBI).. The POWER ON lamp should
be illuminated.
11. Press RESET. The lamp should illuminate. Press START to reactivate the TCU.
Figure 11 - Lamp replacement
TCU40/80 Temperature Control Unit
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