Advice on electrical motor

[hermitish]

Hello all,

Registered in the hope that someone here would be able to give me some advice on a piece of equipment we have where the motor appears to be causing issues. It's a hay bale elevator, basically a conveyor belt that is driven by an electrical motor. It's been standing for a good few years but we've recently tried to get it going and although it runs and everything appears to move freely the motor cuts out after a couple of minutes, i've tried running it without the drive belt so that there is no load on the motor and the same thing happened so i think that the issue is either in the motor or the control box for the motor. it's a single phase 240 volts running off a standard 3 pin plug.

The motor turns very freely by hand and starts OK, have not stripped it down any further than taking the back fan guard off to clear our some cobwebs but it seems in good condition.

The control unit, has the name Brook Control Gear on it, is a little beyond what i am used to. Externally it's an on/off switch; internally, from the looking around i've done on-line, a magnetic switch with adjustable over current protection, in the bottom right of the picture by the blue plastic bit for the off switch and it's already set to the maximum 6 A. I've attached some pictures with labels attached to the unit etc.

Questions i've got are: would there be some issue with the motor that would cause it to draw too much current an trip the safety in the control box without it being obviously hard to turn by hand, in short - should i open up the motor to have a look on the inside? The other option is that there is some problem with the control unit, in that case would there be anything i could look at to confirm the problem and if not does anyone know where i would be able to find a replacement control unit?

Thanks in advance.

 

[Knobhead]

Sounds like a phase down, do you have any electrical test gear? If not I suggest you get an electrician to look at it.

 

[Richard Burns]

Looking at the plate if you are running it on single phase this would be 9 amps (over your trip set) and it looks like it should be running 3 phase in which case Tony's post applies.

 

[Hawkmoon]

You will not be able to identify any of these possible faults by looking so don't bother opening anything up - as Tony says, call an electrician.

 

[hermitish]

Thanks for the replies, with regard to test equipment we have a multimeter but nothing more advanced.

As for the three phase vs single phase question it always worked well before we left it standing for a few years and nothing has changed on the setup so it should just run. I noticed that the plate on the controller indicated it was compatible with a three phase supply but assumed that they had just used a bit of overkill on the controller when they originally put it together and were just running a single phase through it.

Will try to get someone to have a look but in reality unless its a really simple fix then we might as well scrap it.

 

[Marvo]

it's already set to the maximum 6 A.

If you set the thermal overload too high there'sagood chance you'll badly damage the motor.

You need test equipment to go any further, the windings need IR testing and you need to know the run current. You also need to establish the winding arrangement and wiring configuration of the motor. It's probably going to be cheaper and safer to call in someone with experience.

 

[clematis432]

Sounds like a phase down, do you have any electrical test gear? If not I suggest you get an electrician to look at it.

Phase down ? In a single phase motor.

 

[Darkwood]

Yep i noticed that too looks like 1ph with L looped back to 2nd pole assuming original set up judging by the dirty cable coming in stuffing gland ...... where has the motor and control been stood for yrs was it exposed to the elements or damp environment?? Looks like a rust bucket behind the control.

 

[hermitish]

If you set the thermal overload too high there's a good chance you'll badly damage the motor

Haven't increased it, was set to that position when I opened it up, guess we need to find out if the motor is actually trying to pull more than 6A

where has the motor and control been stood for yrs was it exposed to the elements or damp environment?? Looks like a rust bucket behind the controHas been stored in the barn so protected from direct exposure to the elements but its bound to have gotten at least damp.

Has always been stored indoors in the barn but it must have been exposed to at least some dampness over that time. We had a bag over the control and motor as a bit of extra protection as well.

 

[lewlec]

Hi
Is this motor single or three phase?
I imagine its single if it has been working on a plug top?
If single 1 st thing I would do is check out the capacitor, maybe it's a gone a bit weak after being sat idle and the power correction is all wrong. Does your multimeter have capacitor test facility? Hope this is of use.
Regards
Gary

 

[hermitish]

Single phase, multimeter doesn't have capacitor test facility but i have a friendly engineer that i can check with to see if they have something, thanks for the suggestion

 

[Knobhead]

You all know my eyesight is foooked.

Two liable culprits.

There will be a speed switch. After being stood for so long it’s liable to be seized or dirty contacts on the switch.

Or the capacitor, which is easy to test with a 250V Megger.

Given a prod in the side by the other lads, my bet is a dirty speed contact.

Sorry, but the “Megger” is a bit of kit any decent electrician will carry with him. Not something you’re multi-meter can do.

PLEASE, isolate (unplug) the belt before doing anything.

 

[ipf]

You all know my eyesight is foooked.

Two liable culprits.

There will be a speed switch. After being stood for so long it’s liable to be seized or dirty contacts on the switch.

Or the capacitor, which is easy to test with a 250V Megger.

Given a prod in the side by the other lads, my bet is a dirty speed contact.

Sorry, but the “Megger” is a bit of kit any decent electrician will carry with him. Not something you’re multi-meter can do.

PLEASE, isolate (unplug) the belt before doing anything.

Is it Stevie or Tony Wonder.....Just seen it, mate. :shades_smile: