VFD Alarm Troubleshooting

[@Magneticitist]

It's almost like someone else got confused over Sink and Source about halfway through the relay wiring.

[@kcomfortsystemshvac7060]

Hi ,,,nice information,,,,,,,intrestring ,,,,,,,I have little question,,,, 10 and 1 ,,,,are the switch,,,.?

[@building-automation]

@kcomfortsystemshvac7060 terminal 10 is the power supply, putting out 25vdc. Terminal 1 is the input that receives the signal back from the dry contact out the start/stop relay.

[@danieltolfo9332]

Hi this video is what I needed out on the field. Quick question.. does the 25v gets generated from the vfd or it's coming off the rib relay? Thanks.

[@christopherlalla4894]

Vfd the relay is a dry set of contacts

[@danieltolfo9332]

@@christopherlalla4894 are the dry set getting command from bas to enable the vfd? do you wire the cube relay in series with the end switches?

[@building-automation]

@@danieltolfo9332 The 25VDC is generated in the VFD on terminals 9, and 10. The Rib relay and the safety devices are all just dry contacts that allow the 25VDC to come back to the VFD terminal 1, which is configured as the "run enable" input. In this instance there is an added layer of complexity because the "Ice Cube" relays are energized by the safeties and break the 25VDC circuit on behalf of the safeties. Its kind of rare to see that setup. Most of the time the safeties break the 25VDC circuit themselves.

[@danieltolfo9332]

@@building-automation wires that come off the safety would to direct to the coil of relay? How would the other wires be relative to vfd?

[@building-automation]

@danieltolfo9332 yes, the wires from the safeties control the coils of the relays. The 25vdc is run through each relay on the contact side. Normally open and common.