ATS not transferring to gen power

Automatic/Manual transfer switch repair, wiring & troubleshooting questions
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crossdw
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I have a NEXUS ATS (RTSD200A3), which has the 0H7376A controller, connected to a new Generac 20kW (G0070422). The 20kW generator replaced an older 17kW (0055040) which was originally installed with the ATS but died during hurricane Laura. When the new generator was first installed it tested and operated normally with the ATS. But recently during the last couple of outages the ATS detects the loss of utility power and signals the generator to start, but it never switches to generator power. I can manually switch it and everything is good. When utility power is restored the ATS switches back with no issues and the generator shuts down. I've checked the fuses with my multimeter Imageand they're good.
Could this be a controller problem or possibly the relay (0H7259)? What should I check to test this?
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Chris
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That little module in there actually doesn't have anything to do with utility sensing or transferring. The small ice cube relay behind it does the transferring and the generator's controller does the utility sensing. Id be looking for 12V on the 23 and 194 wires during an expected transfer and see if you have voltage. If not, start looking at the wiring for issues.
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crossdw
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I changed out the "ice cube" relay last week and no change in the behavior. I had some time to continue testing this week and so far here is what I have:

- At the generator, when I check voltage using <0-DC Ground> as my negative lead I get +15vdc on <194 - +12VDC> and +15vdc on <23 -Transfer>. I was getting really weird readings on the other end so I ran new wire for all three from the generator to the transfer switch. With the new wire connected - when I test at the generator I am now getting +22vdc on 194 and 23 and get the same voltage at the transfer switch. Not sure where I picked up the extra 7 volts. Now, at the transfer switch there is a terminal strip at the bottom of the cabinet labeled Customer Connections where the wire from the generator is connected for these three leads. The top half of this terminal strip appears to continue on and terminates on the Load Shed Module (0H7376A) on terminals 0-Ground, 194 +12v, and 23 Transfer. Prior to having this trouble, I remember the Priority 1 light being lit green when in Standby but now there is nothing lit on that panel. With this panel connected I get 55vdc on 194 and 23. If I disconnect the leads at the panel the voltage drops back to +22vdc on 194 and 23.

What do I check next?
murphy
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Check the meter you are using. There are no DC voltages that high in the generator.
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