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I took a test for a plant electrician at an automated fruit packing plant. For the practical section I was supposed to connect a VFD to a motor. I can't recall if it was single or 3-phase. There were about 6 wires between the VFD and the motor where I was expecting 3 at most. I think the VFD was an AB Powerflex. I can't find manuals showing all those wires. Can someone please direct me to a manual or tutorial that describes this? Thanks
 

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Allen Bradley has Powerflex user manuals online.

Google will find you a PFD manual you can download in 5 secs or less.
 

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An AB manual won't help you with that.

A drive only has a spot for 3 T-leads unless the motor is DC or has tach leads with it.

You need to find out and understand the windings of the motot and how to connect multi lead motors to get the desired outcome.

Sent from my SAMSUNG-SM-N910A using Tapatalk
 

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It's not going to be in the manual for the drive, because this has to do with the motor. You need a wiring diagram for the motor and the nameplate data.

So if the motor was designed to have been started with a Star-Delta starter, as many refrigeration compressors are, then you will have 6 leads on the motor. You will need to find the motor wiring diagram to identify those 6 leads, then connect them in pairs to where the motor is in the Delta / Run configuration. The drive may or may not have terminals suitable for 2 wires per terminal, so you may need to land your motor leads to a splitter block or Polaris connector first.

Here is an example of a common Wye-Delta motor lead configuration, however there are many types, so this is not gospel.


The other possibility is that you have a 2 speed motor, in which case you must find the lead configuration that corresponds to the High speed and use that with the VFD.

2 speed has numerous connection patterns, you will need to know EXACTLY what you have.
 

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I took a test for a plant electrician at an automated fruit packing plant. For the practical section I was supposed to connect a VFD to a motor. I can't recall if it was single or 3-phase. There were about 6 wires between the VFD and the motor where I was expecting 3 at most. I think the VFD was an AB Powerflex. I can't find manuals showing all those wires. Can someone please direct me to a manual or tutorial that describes this? Thanks
The drive can have multiple wires, two or three are just for the motor, you might have thermistor, speed control, stop / start, remote reset, etc. With a PLC set-up you might have less unless there are some hard controls added.

Cheers
John
 
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