Mag starter noises.

[Rick Fisher]

Anyone know if reversed polarity would cause a mag starter to make a sound resembling a quality dishwasher?

(220V single phase)

I am stumped.

When the motor runs, there is no sound from the switch. When the stop button is locked inward, there is no sound. When I turn the stop button to release it and the green is not pushed, the switch makes an odd sound.

The motor is wired backwards, running in reverse. I havent fixed that part yet.

This may be a question for OWWM..

[Chip Lindley]

I have experienced "chatter" in mag starters with dirty contacts which cause an "almost" make/break of the current energizing the coil. Also the armature of the coil may chatter if rusty or dirty, not making solid contact with its mating part! Reversing a motor should have no effect on a mag starter. A cleaning may be in order!

[Rick Fisher]

This switch is brand new. Right out of the box. The motor is new as well.

I think I will disconnect the motor and try it with just the switch hot.

[Luciano Burtini]

Rick

There is no 'polarity' on AC. In addition, unlike 120v AC, 240v AC is 'hot' on both legs so there is no proper 'polarity' for connecting the starter.

A magnetic starter will have no power to the coil when the circuit is stopped. When you state there is a difference between the STOP button being locked in the 'off' position or not, I start to wonder what kind of starter you have. In a typical industrial starter, the STOP button on the control station is simply a normally closed (NC) momentary contact. It sounds as though your STOP button will latch in the Normally Open position thereby making the START circuit inactive. Unlatching the STOP button then closes the circuit to the START button again allowing the START button to start the machine.

The START button is a Normally Open (NO) momentary contact. When the START button is pressed, the coil engages and both the primary contacts to the machine and an auxiliary set of contacts close. The auxiliary contacts hold the START circuit in the latched position allowing the machine to run even after you release the START button.

The STOP button then breaks the circuit which releases both the primary relay contacts as well as the auxiliary contacts.

Do you have any history on the machine? Was it working previously? Did you modify any of the wiring? Did you change the operating voltage to the starter/machine? I suspect that your starter may be equipped with a 120 volt coil that you are trying to run on 240 volt? Can you confirm the supply voltage as well as the coil voltage of the starter?

Minor humming from a starter is normal, pronounced humming is often related to worn contacts. However, with the circuit off, there should be no humming.

[Rick Fisher]

Thanks for the reply.

The Starter is an NHD. Rated for 220V single phase or 3 phase.

This is a picture of it. The starter is rated for 18 amps - 29amps.



The motor is a Baldor 5hp. 23 FLA, Single phase. This is a picture



Both are brand new, never used.. The motor seems to have 3 capacitors which is new too me. ??

Anyhow. Unlocking the red stop button causes a sound similar to an electric pencil sharpener only quieter.

I disconnected the motor from the starter and plugged it in again. It made no sound. If the motor is wired to T1 and T3, I get the sound.

This confuses me more because the bottom of the switch should be dead without the contacters closed. So why the change?

I am wondering if the switch is kaput out of the box ?

[Rick Fisher]

I wired this switch with one hot on L1 and T1 and one hot on L3 and T3.
Basically copied the diagram for single phase.

The grounds went to the bar on the left.

The hot wires went into the top, L1 and L3 and T1 and T3 went to the motor.

The motor actually ran fine (but backwards ). There was no sound from the starter until I turned it off and unlocked the stop button. (twisted it so I could restart). If I hit stop again, the sound goes away.

There is a factory installed clip going from L1 to L2 and L3 to 13. I left those in place.


The power source is a 30 amp 220V plug which I use to run my planer. I ran the planer and the power is fine. Both the planer and the new motor are 5hp.

[Luciano Burtini]

EDIT

I just re-read your last post. You are stating that the starter works fine and is quiet without the motor connected but it starts to hum if the motor is reconnected?

Do you have a volt meter? If so, make sure that you have no voltage at T1-T3 when the starter is off (check both positions of the STOP button). Make sure that your coil and start/stop circuit is being pulled from L1-L3 (you should have nothing connected to L2).

Engage the start circuit without the motor connected. Ensure that you have 240v across T1-T3 (voltages may vary about 10%)

Double check the wiring on the motor to make sure that it is wired for 240v (there should be a connection diagram on the motor cover).

Is this a factory wired machine (in which case, leave everything alone and talk to your dealer), or are you attempting to wire a new machine/motor?

[Luciano Burtini]

Rick

Where is your START/STOP station? Is it part of the starter or is it separate? I am trying to follow the wiring but a photo is tough to troubleshoot ;-)

[Rick Fisher]

The Motor (Baldor 5hp PH1 220V) and starter are both new and being installed on a restored 24" SCMI Bandsaw. The saw is about 20 years old. I restored the saw for hobby use. It was in a factory for 20 years and was pretty much thrashed.

I figure this saw will last me another 20 years, or more, so I went with all new parts, Guides, Tires, Bearings, Motor etc.

I will bring a volt meter home tomorrow.

As I said before, the motor actually ran fine. Spun the lower wheel etc. It would fire up again. It draws 23 Amps FL and 10 amps Idling. The motor ran backwards which is simple enough to fix, I will reverse the wires.

I cant help but think that I have missed something simple, or the switch is faulty from the factory. I cant figure how a switch can make a sound like that. Its like something is spinning and grinding.

[Rick Fisher]

Rick

Where is your START/STOP station? Is it part of the starter or is it separate? I am trying to follow the wiring but a photo is tough to troubleshoot ;-)

The starter is just a normal old stationary tool starter. I dont have it attached to the saw because its easier to wire when I can hold it in my hands.

In the photo, I just put it on the motor. When I get it right, I will attach it.

Its an "all in one" unit. No different than you would find on any planer from Grizzly.

It looks exactly like this.

[Luciano Burtini]

Okay

So the START & STOP are contained within the starter. You should not have to do anything other than:

1. Ensure that the starter COIL voltage is 240v (and not 120 volt)
2. Connect your Power Lines to L1 & L3
3. Test the starter
4. If all is well, connect motor to T1 & T3

Did you get a wiring diagram with this starter? I have no idea why they would have placed a jumper from L1-L2. The jumper from L3-13 is to complete part of the start circuit. 17-18 appears to be your START button, but I don't see a STOP button leading me to believe that this starter may not use traditional 3 wire control. However, although I am familiar with most industrial starters, I am not familiar with these Asian copies, so this is speculation on my part.

BTW, reversing the motor leads between T1 & T3 will NOT correct rotation. Rotation will need to be addressed by changing motor leads in the motor J-box (assuming the motor is reversible). Follow the motor wiring diagram.

[James Walters]

Make sure the green starter button is fully releasing, it's spring loaded.
It happened to me!!!!!

[Rick Fisher]

I made a call to Baldor and asked about reversing the direction on the motor. They said to swap the red and black wires.

There are 3 black wires..

This is frustrating..