Kohler 180-400REZX, 180-400RZX Industrial Generator Sets Wiring Diagrams (tp6713)

These Kohler 180–400REZX / 180–400RZX industrial generator sets usually sit in plants, hospitals, or commercial buildings, kicking in when the mains drop. This wiring diagram set is what I’d pull out when I need to trace control circuits, confirm terminations, or make sure a harness repair matches factory routing. If, for example, the set won’t start from the automatic transfer switch but cranks fine locally, this is the document I’d use to follow the signal from the ATS, through each connector and relay, until I find where it dies.

Applications & Use Cases

• Trace wire routing from control panel to engine, alternator, and sensors to verify correct harness installation.
• Isolate faults by checking which connectors, relays, or terminals sit between a dead circuit and its power source.
• Continuity-test repairs after splicing or replacing sections of loom, confirming pin-to-pin paths match the diagram.
• Plan retrofits for monitoring, remote start, or alarms by identifying safe tie-in points and return paths.
• Verify connector logic so each pin is carrying the right signal before you power the system back up.

FAQ

Q: Can I use this on a tablet in the field?

A: Yes, it works well digitally; you can zoom into connector callouts and wire labels without losing detail.

Q: Is it worth printing parts of it?

A: I’d print the specific diagrams for your exact model and keep them laminated near the set for faster fault tracing.

Safety Note

Always lock out the generator and verify all circuits are de-energized before opening panels or probing any wiring.

Kohler 180-400REZX, 180-400RZX Industrial Generator Sets Index:

Wiring Diagram Cross-Reference
Generator
Set
Model No. Hz
Generator Set
Spec No.
Wiring
Diagram
Version No.
180REZX 60 GM66347-GA1, 5 1
180RZX 50/60 GM66347-GA3, 7 1
200REZX 60 GM66347-GA2, 6 1
200RZX 50/60 GM66347-GA4, 8 1
250REZX 60 GM65754-GA1, 3 2
250RZX 50/60 GM65754-GA2, 4 2
300REZX 60 GM71300-GA1, 2 3
300RZX 50/60 GM71300-GA3, 4 3
350REZX 60 GM71300-GA5, 6 3
350RZX 50/60 GM71300-GA7, 8 3
400REZX 60 GM69630-GA1, 3 3
400RZX 50/60 GM69630-GA2, 4 3

Kohler