Removal and Replacement Procedures
74 of 82
5
Reinstall in reverse order.
10.4.6 Solid State Relays
Mark all wiring before removal. To replace the SSRs, proceed as follows:
1
Remove system AC power at the source.
2
Disconnect the DC control wiring, right side of SSR, screws 3 & 4.
3
Disconnect the AC control wiring, left side of SSR, screws 1 & 2.
4
Remove the screws holding the SSR to the white backing panel.
5
Reinstall in reverse order.
10.4.7 Valves
If an electrical valve should fail, it can be replaced as follows.
1
Remove Glovebox AC power. Do not assume that the valve is off and will stay off, because
the PLC can switch a valve on due to an external event.
2
If the GA valve is being replaced, ensure that the gas supply is off.
3
If the VA valve is being replaced, ensure that the vacuum source is off.
4
Remove the electrical connection by loosening the center screw.
5
Remove the solenoid by removing the four top screws.
6
Replace the new solenoid in reverse order.
7
Turn on the gas and vacuum supply, and power on the system.
8
Test the new valve for operation and for leaks.
10.4.8 Vacuum Pump
To replace the vacuum pump, proceed as follows.
1
Remove box AC power. If the vacuum pump is powered separately from the system, ensure
that the power is removed.
2
Disconnect the clamp from the pipe.
3
Disconnect the AC line cord.
4
Remove the bolts that secure the pump to the box frame.
5
Remove the old pump.
6
Install the new pump in reverse order.
7
Ensure that the new pump has the proper oil and that the oil level is correct.
8
Power on the system and test for proper operation.
159
