Woodward Vertex-Pro, Installation/Hardware Manual

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Manual 26489V1 Vertex-Pro Motor-Driven Compressor Control
Woodward 83
9.3.4—Replacing a Relay Box
If power has not been removed from the control system, power will
be active at the module and also at the cable connectors. It is
recommended that the cables not be removed until after the module
has been unseated. If cables are removed with power applied, care
must be used to avoid shorting cable connector pins.
HIGH VOLTAGE—If there is high voltage on the relay box terminal
blocks, there will be high voltage on the relay box connectors. For
this reason, all power should be removed from the relay box terminal
blocks before disconnecting any cables.
1. Carefully—to avoid shorting cable pins—disconnect all I/O cables from the
relay box, and secure cable ends to avoid damage or shorting of pins. The
I/O cables use a slide latch (to disengage, slide the latch to the release
position).
2. Disconnect all field wiring. Care should be taken to avoid shorting the wires.
3. Install the replacement relay box.
4. Reconnect all field wiring.
5. Connect all I/O cables to the relay box, being careful to avoid shorting cable
pins. Lock the connector in position by sliding the latch to the latched
position.
6. If power was removed, reapply power.
7. Put the CPU module back in run mode.
8. Verify that the new relay box is working correctly.
9.3.5—Replacing a Receptacle-mounted Relay
HIGH VOLTAGE—When there is high voltage on the relay contacts,
there will be high voltage on and around the relay itself. For this
reason, all power must be removed from the relay box before
replacing the relay.
1. If possible, remove all power from the control system and the Relay module.
2. Identify the faulty relay.
3. Move the relay’s hold down spring out of the way, and pull the relay out of its
socket.
4. Insert a replacement relay with same manufacturer’s part number into the
vacated socket, and re-engage the hold down spring.
5. Restore all power if previously removed.
6. Verify that the new relay is functioning correctly.