We will need an outage to replace the NI 9074 CompactRIO System Master Controller (SMC). Should only take about 30 mins but let’s say an hour at the longest. Have whoever is doing the outage to get familiar with where everything is and where to measure voltages before taking the outage.
Please let me know when you can schedule the outage so that I can be available with any questions.
Below are the steps to replace a NI 9074 CompactRIO System Master Controller (SMC):
WARNINGS:
1) DANGER HIGH VOLTAGE (APPROX 200 VAC) ON WIRES #: 411, 412, 413 and 495 on Module “NI 9225” in SLOT 7 of 8 as shown in the picture below:
2) DO NOT DISCONNECT CURRENT TRANSFORMER WIRES 407, 408, 409, 417, 418 or 419 FROM MODULE “NI 9227” IN SLOT 8 OF 8.
1) Before the outage, take a picture of the SMC modules and the SMC power plug (shown below) to remember what order they were in as they will need to be put back in the same order.
2) Switch control of the diesels from the SMC to the Easygens by changing all diesel Easygens into “MANUAL MODE”. This will keep any diesels currently operating from stopping
3) Open the feeder breaker for the outage.
4) Stop all the diesels and lock them out.
5) Confirm diesel bus is dead by measuring all phase to phase voltages and all phases to neutral.
6) Open the circuit breaker than powers the 24 VDC supply which is CB8 as shown in the picture below:
7) Measure AC voltage between the terminals with wires #: 411 and 495, 412 and 495 and 413 and 495 (as shown below) to confirm they are de-energized. 
8) Test “DC voltage” on multimeter between the terminal “V” (wire # 640) on the SMC power plug (highlighted in red below) with red probe and terminal (wire #: 28) with black probe to confirm 0 volts. If 0 volts, unscrew the connector and unplug it and secure it so it’s wires don’t touch any other wires or on the metal backplane of the Master Cabinet. Please send back the new SMC power plug along with the old SMC if reusing the old SMC power plug?!
If not 0 volts, stop and call FPS personnel.
9) Unplug the Ethernet cable going to port “1” on SMC and secure the cable.
10) Unplug all the SMC modules by pushing in on the silver latches (labelled #2 in picture below) on the top and bottom of each module and pulling towards you. After removing them from SMC, secure them so their wires don’t touch each other or the backplane of the cabinet. Here is a picture of how to install the modules:
11) Remove the SMC from its DIN rail mount by pulling down on the entire controller to compress the 2 springs and pulling the bottom towards you at the same time. Once the bottom is free, push the SMC upward to clear the top of the DIN rail. Here is picture of the DIN rail mount:
12) Unscrew the green ground wire from the chassis grounding terminal (labelled #1) of the NI 9074 with a #2 Philips screwdriver.
13) Unscrew the 2 screw holding the SMC onto the DIN rail mount with a No. 2 Phillips screwdriver.
14) Reverse the previous steps with the new compactRIO 9074 to install the SMC.
15) After powering up the new SMC, if the SMC is running properly, the “User 1” green LED on the SMC should start to flash after booting up for 5 minutes.