Tic tracer motor rotation

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shputnik

shputnik

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Utah
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Expert wirenut installer
Is there a "tic tracer" type handheld tool that can be used to check motor rotation? Basically guy holds it to leads and can determine the motors rotation clockwise or counterclockwise

Someone mentioned that in Europe they had something like that
 
shputnik said:
Is there a "tic tracer" type handheld tool that can be used to check motor rotation? Basically guy holds it to leads and can determine the motors rotation clockwise or counterclockwise

Someone mentioned that in Europe they had something like that
Click to expand...
A rotation meter? Or something else?


Knopp Rotation Meter | Phase Rotation Meter | J Harlen Co

Knopp Phase Sequence Rotation Meter K3 With Case 4403050
www.jharlen.com

This one tests a motor before it gets connected so you can do it once and done.

 
A Fluke T+ Pro test for phase rotation. I used to have a meter that tested motor rotation, but it was easier to connect and see rotation. 50/50 chance on getting it correct.
 
Here's a dumb question. Haven't delt with many 3ph motors so not sure of phase sequencing. On a 3ph system if looking at the panel is there a standard of phase sequence that has A,B,C phase hitting peak in sequential order, and specific placement other than a highleg installation position requirements? Or is there enough randomness that you can never tell and would always need to have a meter that will judge the sequence?
Was just thinking as I do deal with some 208Y installation and do try to find way of install that makes the life of the next guy working on it easier. Any benefit to phase sequencing within the panel installation?
Also I suppose when replacing a 3ph panel marking of relative position critical especially where motor loads might be involved.
 
Fred B said:
Here's a dumb question. Haven't delt with many 3ph motors so not sure of phase sequencing. On a 3ph system if looking at the panel is there a standard of phase sequence that has A,B,C phase hitting peak in sequential order, and specific placement other than a highleg installation position requirements? Or is there enough randomness that you can never tell and would always need to have a meter that will judge the sequence?
Was just thinking as I do deal with some 208Y installation and do try to find way of install that makes the life of the next guy working on it easier. Any benefit to phase sequencing within the panel installation?
Also I suppose when replacing a 3ph panel marking of relative position critical especially where motor loads might be involved.
Click to expand...

There are no dumb questions…🙂

Much less headaches to just land your wires and get it right at the motor or drive.
You will never know how it turns out when the POCO connects anyway.

Had one installation where the electrician went through and made sure all his motors were wired the same so he would have them all correct when it was connected.. checked them with a rotation tester.
We connected our end.
He called back and told me our rotation was wrong with a pissy attitude. I quickly reminded him on new installs rotation wasn’t our responsibility. Look at the policy.
Once his attitude changed I decided to try to help him out. This was an asphalt plant, so it was several motors.
We went there and I had the guys simply switch the elbows on the UG PMT.

The original motor he checked was rotating correctly. He went through and checked more of them.
whoops, found one backwards..
Now another, this ones right, this one’s backwards… you get the gist…

I had the guys put the elbows back like original and he changed motor rotation on the ones that were wrong.

He would have saved a lot of headache by not worrying a day or two with the phase tracer and just connecting them and bump starting them to fix them.
 
Hv&Lv said:
There are no dumb questions…🙂

Much less headaches to just land your wires and get it right at the motor or drive.
You will never know how it turns out when the POCO connects anyway.

Had one installation where the electrician went through and made sure all his motors were wired the same so he would have them all correct when it was connected.. checked them with a rotation tester.
We connected our end.
He called back and told me our rotation was wrong with a pissy attitude. I quickly reminded him on new installs rotation wasn’t our responsibility. Look at the policy.
Once his attitude changed I decided to try to help him out. This was an asphalt plant, so it was several motors.
We went there and I had the guys simply switch the elbows on the UG PMT.

The original motor he checked was rotating correctly. He went through and checked more of them.
whoops, found one backwards..
Now another, this ones right, this one’s backwards… you get the gist…

I had the guys put the elbows back like original and he changed motor rotation on the ones that were wrong.

He would have saved a lot of headache by not worrying a day or two with the phase tracer and just connecting them and bump starting them to fix them.
Click to expand...
Would I be correct in that with motor running reversed swapping L1 and L3 would all be needed to correct? A little more complicated if motor only bumps not run, that could be L1/L2 or L2/L3 reversed?
 
Fred B said:
Here's a dumb question. Haven't delt with many 3ph motors so not sure of phase sequencing. On a 3ph system if looking at the panel is there a standard of phase sequence that has A,B,C phase hitting peak in sequential order, and specific placement other than a highleg installation position requirements? Or is there enough randomness that you can never tell and would always need to have a meter that will judge the sequence?
Was just thinking as I do deal with some 208Y installation and do try to find way of install that makes the life of the next guy working on it easier. Any benefit to phase sequencing within the panel installation?
Also I suppose when replacing a 3ph panel marking of relative position critical especially where motor loads might be involved.
Click to expand...
Problem is unlike a DC source where difference between poles of the source has definite characteristics AC sources don't have such definite characteristics. Single phase three wire, only thing that is definite is the center tap. Three phase (other than a neutral, grounded phase, etc.) there is no definite differences in the "phase conductors" either. There is phase rotation, but there is no definite A B or C until someone designates them. You could specify it must be clockwise rotation but still could pick any source lead and designate it A and then would need to examine actual rotation to determine which ones to designate B and C from there.
 
I usually just land the wires and then check rotation and reverse as needed. UNLESS the motor is hooked up to a pump or piece of equipment that could be damaged by spinning backwards. Some pumps have a ratcheting mechanism for rotation that could be damaged if the motor is stated DOL backwards.
 
Fred B said:
Would I be correct in that with motor running reversed swapping L1 and L3 would all be needed to correct? A little more complicated if motor only bumps not run, that could be L1/L2 or L2/L3 reversed?
Click to expand...
Pick any two.
 
SSDriver said:
I usually just land the wires and then check rotation and reverse as needed. UNLESS the motor is hooked up to a pump or piece of equipment that could be damaged by spinning backwards. Some pumps have a ratcheting mechanism for rotation that could be damaged if the motor is stated DOL backwards.
Click to expand...
For those types it pays to decouple then check
 
SSDriver said:
I usually just land the wires and then check rotation and reverse as needed. UNLESS the motor is hooked up to a pump or piece of equipment that could be damaged by spinning backwards. Some pumps have a ratcheting mechanism for rotation that could be damaged if the motor is stated DOL backwards.
Click to expand...
Typical irrigation well motors around here have ratcheting mechanism. We bump them all the time on first run to check rotation. If motor just hums it is wrong rotation. You only need to bump for however fast you can press the start button then hit the stop with other hand. Wait too long and you probably will blow a fuse before you damage that ratchet mechanism. The mechanism is mostly there so the well shaft doesn't spin backward when you shut it off and water is draining back down the well casing.
 
kwired said:
Typical irrigation well motors around here have ratcheting mechanism. We bump them all the time on first run to check rotation. If motor just hums it is wrong rotation. You only need to bump for however fast you can press the start button then hit the stop with other hand. Wait too long and you probably will blow a fuse before you damage that ratchet mechanism. The mechanism is mostly there so the well shaft doesn't spin backward when you shut it off and water is draining back down the well casing.
Click to expand...
After the local vertical pump guy told me they get them from time to time with all the ratcheting teeth shattered I don't do that anymore.
 
SSDriver said:
After the local vertical pump guy told me they get them from time to time with all the ratcheting teeth shattered I don't do that anymore.
Click to expand...
What size motors and are they direct drive or are they speed reduced by gearbox, pulleys, etc?

Most what I have done this with is 50-100 HP direct drive motors.

Most of them have like a 1000 feet or more of conductor to the source and that likely does limit starting torque to some extent also.
 
3 phase AC & Refrigeration compressors if they are scroll compressors (which they are all now) they are phase sensitive. Bumping it to check for a few seconds won't hurt it. Two ways to tell if its right or wrong. Put ac gauges on it, it won't pump much going backwards. Or check amps. Low amps it's going backwards.

We say 50-50 chance on rotation but I know of a job that the "contractor" turned on all the ac unit without having an ac guy out to check and they had to replace 80% of the compressors
 
kwired said:
What size motors and are they direct drive or are they speed reduced by gearbox, pulleys, etc?

Most what I have done this with is 50-100 HP direct drive motors.

Most of them have like a 1000 feet or more of conductor to the source and that likely does limit starting torque to some extent also.
Click to expand...
Most of the ones I deal with are direct drive 20-100HP for commercial pools and water slides. Starters are usually 5' to 20' away only. Newer stuff is all on VFDs so it's not an issue on those.

EDIT: Just to clarify I haven't seen it first hand but the local vertical pump company told me it does happen and to avoid reverse rotation if possible. Only takes me an extra 2 min to pull out my rotation meter and check. So far my meter has been correct.
 
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