Fuse blowing to one side of a pair of electric gates - Any ideas

[gray]

I have a pair of electric gates, with underground motors.

One side works OK, the other side works when closing, but blows its associated fuse when opening.

Swopped all the connections over, and ascertained its not the controller thats faulty.

The motor has 3 wires going to it. I am not sure if this is 3 phase or if the motor has 2 windings one for forward the other for reverse with a common.

The fuses are 5mm x 20mm F1.6AL which is a quick blow (so I assume the fuses are also protecting the semiconductors in the control box). The leaflet says the fuses are 'motor' fuses, so I would have thought they should be slow blow. But as its been running OK for over 1 year, I will leave them as quick blow.

Any body got any clues or ideas.

Also has anyone ever had any dealing with 'Proteco', especially in trying to get something repaired / replaced under there 3 year manufacturers warranty.

[R]

Unless you've 3 phase at the property it's unlikely to be that. More like , as you say, a common return with the switched positives for forward/reverse. Try swapping the motor 2 positives, if it then blows the fuse when operating the opposite way you can narrow it down to the motor itself. Could be as simple as water ingress or a dodgy winding somewhere. Unless the gearing is sticking as well causing an overload.

1.6a sounds a little low. Perhaps protecting other electronics as well.

[RubberBiker]

Might be a servo motor:

[Peter]

Spent some time today on a simelar problem. In this case three wires were live to open gate...live to close... neutral.(doubled up for two gates)

His problem was that one gate was tripping the rcd and mr. gateman offered him £350 worth of new motor.

I connected neutral from the power cable to neutral from motor. power live alternately to motor open/close lives in an attempt to trip the rcd.

S'not the motor.Summit in the gate control, maybe relays, but a new board is £100, somewhat less than a new motor.

Peter

[gray]

There is no earth fault as Earth Leakage does not trip.

I have just found the instructions, and it looks like 2 seperate windings in the motor.

OPEN (Brown cable) Common (Blue or Grey cable) CLOSE (Black cable)

Seperate capacitor across OPEN and CLOSE terminals.

I suppose I could check resistance of the 2 windings and see if they are different.

Hopefully it will be a valid warranty claim as its 3 years.

I will have to speak to suppliers on Monday.

Will they need the board and the single motor.

I have tried buying spares before from 'them' and they only want to sell a complete boxed kit of parts, but at £600 ish thats too much.

[gray]

I believe all sevo motors are 2 wire with pulse width determining which rotation. But I am not 100%

1.0ms +45° (clockwise rotation) 1.5ms zero position 2.0ms -45° (anti clockwise)

Would the signal be a DC signal or AC.

[<me9]

I suspect that they will be split phase induction motors, with a capacitor connected permanently between the two 'lives', either in the motor or the controller. Swapping the live feed will reverse the motor. This is the standard method used in tumble driers to reverse the drum.

[gray]

Yes there is a cap between forward and reverse in the controller.

Not knowing much about tumble driers, I suppose that each winding is just pure 240v AC then.

[John]

Are you positive that the mechanism is as friction free as possible. I see some that are really in need of a bit of lubrication.

[gray]

Yes - all I have is the shaft and chain wheel sticking out of the motor / gearbox. Nothing else connected.