Voltage spikes on motor startup

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I am off-grid and I (naturally) experience voltage spikes each time an induction motor starts. In my case the major contributors are the fridge, well pump and air compressor. I can see on my Sense meter that the maximum values are well within the capacity of my inverter (Magnum MS4448PAE), but my question is, is this the best thing for the inverter, and, is there anything I can do to reduce the levels?

 

[timselectric]

If the spikes aren't overloading your inverter.
Then I wouldn't worry about it. Spikes (surges) are normal. And the Magnum should have no issues with them.

 

[photon_trap]

Thanks timselectric

 

[Farm Boy]

If the spikes aren't overloading your inverter.
Then I wouldn't worry about it. Spikes (surges) are normal. And the Magnum should have no issues with them.

Looking over the threads to find info on spikes related to inrush I found you here, so you'd probably be the best fellow here to ask. I checked the inrush and running amp of my compressor as the kpv is not starting it at this point. On the meter it shows 32amp on 1 leg and close to 40 amp on the other for about a second. After start up shows 16.5 A -leg 1 and 20 A - leg2 running amps. SS offers several soft starts. After looking them over if you have a chance, could you recommend 1 of them for this? I checked this close to the compressor for these reading. At the farthest point of the run closest to the inverter, the readings of inrush seem to be much less. These reading were done with utility grid. Reading on motor: Baldor Cat.No. 2023000868 / HP5 / V 230 / AMPS 22 / Frame 184T / HZ 60 /PH 1 / SER.F. 1,15 / code j / DES. L / CLASS F /NEMA NOM. EFF. 82.5% / P.F. 89%

 

[timselectric]

Looking over the threads to find info on spikes related to inrush I found you here, so you'd probably be the best fellow here to ask. I checked the inrush and running amp of my compressor as the kpv is not starting it at this point. On the meter it shows 32amp on 1 leg and close to 40 amp on the other for about a second. After start up shows 16.5 A -leg 1 and 20 A - leg2 running amps. SS offers several soft starts. After looking them over if you have a chance, could you recommend 1 of them for this? I checked this close to the compressor for these reading. At the farthest point of the run closest to the inverter, the readings of inrush seem to be much less. These reading were done with utility grid. Reading on motor: Baldor Cat.No. 2023000868 / HP5 / V 230 / AMPS 22 / Frame 184T / HZ 60 /PH 1 / SER.F. 1,15 / code j / DES. L / CLASS F /NEMA NOM. EFF. 82.5% / P.F. 89%

This is an air compressor?

 

[Farm Boy]

This is an air compressor?

Yes. it is a Quincy. 80 gal.

 

[timselectric]

Yes. it is a Quincy. 80 gal.

Quincy is a hard one to start. (But they last forever)
I would think that the 1P16-32 would help, if you can access all of the wiring.

 

[Vigo]

Im a little confused on what readings could be less near the inverter than they are near the compressor. If you are reading current on the same circuit at two different places, and there are no other loads or sources on that circuit, the readings should be identical (within the margin of error).

 

[timselectric]

Im a little confused on what readings could be less near the inverter than they are near the compressor. If you are reading current on the same circuit at two different places, and there are no other loads or sources on that circuit, the readings should be identical (within the margin of error).

I think that it was just the meters ability to see it quickly enough. Or the lack of.

 

[740GLE]

My guess is starting caps causing the spikes.

An 80gal compressor prob has a 1-3hp motor? Not an easy load to manage.

 

[Farm Boy]

I think that it was just the meters ability to see it quickly enough. Or the lack of.

I am kinda thinking that as at the inverter the wire run at that point is approx., 160' away.

 

[Farm Boy]

My guess is starting caps causing the spikes.

An 80gal compressor prob has a 1-3hp motor? Not an easy load to manage.

it has 2 large capacitors on top of the 5hp motor.

 

[timselectric]

I am kinda thinking that as at the inverter the wire run at that point is approx., 160' away.

It shouldn't matter.
Amperage is constant throughout the circuit.

 

[timselectric]

I think that the meter just didn't catch it.

 

[Farm Boy]

Meter is a Southwire, not sure how correct it is from one insulation type to another.

 

[Farm Boy]

I will check into the 1-p16-32. Thanks for your help.

 

[740GLE]

it has 2 large capacitors on top of the 5hp motor.

Yeah one is probably a starting cap the other is a run cap.

You also notice the same voltage spikes with other stuff? Or is it just a lesser degree?

 

[Farm Boy]

Yeah one is probably a starting cap the other is a run cap.

You also notice the same voltage spikes with other stuff? Or is it just a lesser degree?

Basically I was searching threads related to inrush and came to this one on voltage spikes and may have not been the proper place to ask but I seen timselectric here helping out and thought id ask. It's all about getting my compressor to start using my inverter which trips out trying with out a soft start. I really don't have any voltage spikes while on utility grid that ive ever cared to check into but with my inverter not able to start the compressor is when I started taking reading of amps at start up and found the inrush or possible spikes as referred to here where I brought this up. I guess I was thinking spikes and inrush were related but Ive been wrong a few times. Hope you have a nice day and thanks for your input.

 

[HarryN]

I am not sure if it would work on your compressor or not, but there are some fairly sophisticated motor controllers that ramp up the rpm slowly vs going right to full blast.

Sometimes they are called variable speed drives / variable frequency drives but there might be another name.

You do need to be careful to not run the motor at too low of rpm for a long time as they depend on the fan rpm to cool.

The price of these has been coming down a lot over the past 20 years.

 

[timselectric]

Basically I was searching threads related to inrush and came to this one on voltage spikes and may have not been the proper place to ask but I seen timselectric here helping out and thought id ask. It's all about getting my compressor to start using my inverter which trips out trying with out a soft start. I really don't have any voltage spikes while on utility grid that ive ever cared to check into but with my inverter not able to start the compressor is when I started taking reading of amps at start up and found the inrush or possible spikes as referred to here where I brought this up. I guess I was thinking spikes and inrush were related but Ive been wrong a few times. Hope you have a nice day and thanks for your input.

To clarify.
Your "spike" is "inrush" to start the motor.