Three phase motor capacitor wiring help

[Smouser]

I have a VFD I could potentially use to test the motor. However, my VFD is only rated at 1.5kw and the kotor is 2.2kw.

Could my VFD be used to test the motor without a load?

 

[daleyd]

I have a VFD I could potentially use to test the motor. However, my VFD is only rated at 1.5kw and the kotor is 2.2kw.

Could my VFD be used to test the motor without a load?

Yes, I’ve run a big motor (2.2 kw) off smaller drive (0.5 kw) - with no load it should run fine

 

[Agroshield]

I have a VFD I could potentially use to test the motor. However, my VFD is only rated at 1.5kw and the motor is 2.2kw.

The 2.2kW is for pushing a wet, green, 4" thick oak plank through a blunt blade. A bare motor, maybe without even a pulley connected will desire way less than this.

For good, brand name VFDs, the rating is its 100% duty cycle (unlike most welders). They will stand 150% or 200% of their rating for a short time.

To really be conservative, set the VFD for a long ramp-up (greater than 5s) time. The VFD is smart enough to protect itself in case of an overload.

 

[Smouser]

The 2.2kW is for pushing a wet, green, 4" thick oak plank through a blunt blade. A bare motor, maybe without even a pulley connected will desire way less than this.

For good, brand name VFDs, the rating is its 100% duty cycle (unlike most welders). They will stand 150% or 200% of their rating for a short time.

To really be conservative, set the VFD for a long ramp-up (greater than 5s) time. The VFD is smart enough to protect itself in case of an overload.

Great. Thanks for the info.

I have got only branded VFDs. One Bosch Rexroth and two ABB VFDs. All three is 1.5kw.

The motor settings is going to be troublesome. I have NOTHING to go off by.

I might need to google the specs on a similar sized motor and try those settings.

 

[brightspark]

Great. Thanks for the info.

I have got only branded VFDs. One Bosch Rexroth and two ABB VFDs. All three is 1.5kw.

The motor settings is going to be troublesome. I have NOTHING to go off by.

I might need to google the specs on a similar sized motor and try those settings.

thats an old motor you have the modern ones dont have as many windings

 

[Smouser]

Small update.

I could not get the motor to run with my VFD when connected up as DELTA. I checked and re checked that I have the correct wires together.

When it tried to conduct the ID run it just threw up an error.

I tried multiple parameter settings but to no avail.

In desperation I tried to run it in STAR and it ran??

I am not all sure what the hell is going on there.

 

[Seadog]

You might have one of the phases reversed. Does the motor sit and hum rather than turn?

 

[Smouser]

It does absolutely nothing when in DELTA. No hum, no noise, nothing at all. When turning the shaft by hand while it is powered it is as free as it normally is when no power is applied to it.

I am at a loss with it to be honest.

 

[brightspark]

just get a second hand single phase motor and bang it on job done

 

[Smouser]

just get a second hand single phase motor and bang it on job done

You are right. BUT it will never be as cool as this old motor. It is so heavy and solidly built. I can't bear seeing it go to the scrap heap.

 

[brightspark]

It will definitely not just be scrapped! Too much copper in it, so it will def be recycled.

could you realy be botheredi save copper but only what i have taken out of jobs and have a machine i made for stripping cable real fast

 

[hotponyshoes]

could you realy be botheredi save copper but only what i have taken out of jobs and have a machine i made for stripping cable real fast

Have you checked the scrap price recently?

 

[Smouser]

My motor is NOT getting scrapped, recycled or otherwise disposed off. It WILL run!

 

[Agroshield]

Could you show us a picture of the way you have connected it for running in delta. There might be something subtle that you have missed.

 

[m_c]

What error did the VFD show?

 

[Smouser]

Could you show us a picture of the way you have connected it for running in delta. There might be something subtle that you have missed.

I did not take a photo and was typing a lengthy reply of how I am SURE I connected it up correctly explaining what I have done.

While typing I realised I did indeed make a mistake with the connections .

Oopsy.

Thanks for questioning the connections. I had myself convinced it was correct the first time but it was not.

I will try the motor later today with it CORRECTLY wired in DELTA.

 

[Smouser]

The motor runs in DELTA!

I feel very sheepish.

I will tell you how I wired it incorrectly.

The terminal block was wired like this below.

I stupidly did not check and just assumed the wiring block will be "ready" for wiring to DELTA with the black wires in the 'correct' order.

Just link the red and black wires from the top, middle and bottom terminals to make it delta (I did remove the wire connecting U2, V2 and W2).

But what I needed to do was to make sure the black wires were in the right order.

The order of the black wires should have been as indicated in the below photo.

A proper facepalm moment.

O well, you live and learn. The motor runs in DELTA and STAR on the VFD without any errors.

Now I can finally return to the original purpose of the thread of trying to make the motor run with capacitors.

 

[Seadog]

The block is wired correctly. Strapping across each pair should have worked.

Is the labelling taken from the wires or from the block? Or, are you assuming that the wiring plate information is as they are presented?

 

[Smouser]

The block is wired correctly. Strapping across each pair should have worked.

Is the labelling taken from the wires or from the block? Or, are you assuming that the wiring plate information is as they are presented?

The block is wired correctly now (second photo) and the motor runs in DELTA.

The way it was wired originally (first photo) it did not work.