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neksmerj
22nd December 2007, 09:33 PM
Dear members,

I have just purchased a new 240V single phase reversible motor for my lathe, and a reversing drum switch, similar to a Dayton.

The lathe came without motor and controls.:no:

I need some assistance in working out a schematic wiring diagram, showing the motor connections to the reversing switch and the mains.

I have attached a wiring diagram for the motor, and a wiring diagram of the reversing switch.

Any assistance would be greatly appreciated.:2tsup:

Merry Christmas,

Ken

neksmerj
22nd December 2007, 10:25 PM
Dear members,

I'm not an electrician's bootlace, but I think I may have figured out my own problem.

Please comment on the attached wiring diagram.

Ken

malb
23rd December 2007, 02:25 AM
Ken, your wiring diag looks ok, except that the configuration labelled Forward is the reverse configuration shown on the motor supply diagram, and vice versa.

If need be you should be able to change this by connecting the yellow to terminal 4 and the blue to terminal 1 of the switch.

Does the reversing switch have a centre off position so that you can use it as FWD OFF REV, or do you need to add an ON OFF prior to the rewersing switch? Also have you considered a Knock Off style isolating switch in case of emegency?

It is essential that the motor cannot be reversed while running, as this is dangerous to the motor and the can throw the chuck, endangering the lathe, work and user. For this reason alone, I would consider some form of mechanical lockout for the reversing switch handle.

neksmerj
23rd December 2007, 01:09 PM
Hi Malb,

Thanks for your advice. I won't know which way the motor runs until I try it, so swapping the leads should fix that problem.

The switch does have a centre off position, I just didn't show it on the diagram.

I have been informed that the motor will continue to run in the same direction, even if the switch is accidently knocked into the opposite direction. There's little chance of this happening, as the switch has really positive indents at the 3 positions, and takes a bit of effort to move the handle.

I'm not sure how to add a mechanical lockout, if this proves necessary. Any clues?

I do intend putting in a 2 pole emergency stop button at knee height, on the front of the cabinet.

A separate isolating switch won't be necessary, as the mains lead will be plugged into a power point.

Ken

neksmerj
23rd December 2007, 01:46 PM
Following advice from Malb, I have revised my wiring diagram.

If you have any comments, please let me know.

Ken

thatirwinfella
23rd December 2007, 05:09 PM
that last diagram seems correct, my only concern is the colour of the brown neutral; brown is typically an active conductor for appliances. Off the top of my head, it wouldn't make much difference to the operation of the motor.

an estop is a good way to go, a double pole is even better. As the motor does not have aappear to have a contactor, i would choose a latching estop. this way, when the estop is pushed the motor will not restart once pressure is released.

neksmerj
23rd December 2007, 06:29 PM
Hi Thatirwinfella,

The motor was made in India, (did not find this out until it arrived), so who knows what colour coding and terminology they use.

Is there a way to determine which lead on the motor is active, and which is neutral?

Good point about a making the emergency stop button, self latching.

Ken

malb
24th December 2007, 03:38 PM
Ken, I have a number of ES switches that I bought for my workshop about a year ago. Button 50mm round (red) x 20 deep, housing 32mm sq x 50 deep, with 1 set of NO contacts and an independant set of NC contacts. Rated 240VAC @6A, so would handle your motor according to the data supplied. Can drop one off for you gratis if it's any use for the lathe. Only problem I can see is that you can only switch active, rather than active and neutral. Send a PM if interested.

When I mentioned a mechanical lockout for the reverse position on the switch, the things that come to mind were a spring pin in the switch handle that you need to lift to move to reverse, or a hinged arc segment in accrylic that normally blocks the reverse section, but could be lifted to select reverse when required.

If you do have a strong detent set and the switch does have a an OFF position, a lockout system should not be required.

Mal