Can anyone advise on electrical wiring and electrical parts
|Nick Plumb 1||10/01/2020 12:12:27|
|3 forum posts|
I've recently acquired a Mk1 Bantam. Acting on advice I've purchased and have it running on a Clarke P20 phase inverter. Woo hoo... it runs! and so does the coolant pump! But on further examination the e-stop doesn't work and neither do the contacts that shut down power on the brake and also the gear cover. So in essence it's not safe to use. Further investigation revealed that the wiring inside the e-stop and speed selector box has been butchered !! The e-stop electro-mechanical switching unit is missing and all the wires have been taped-up. The 2 speed switch is functional.
So I'm not sure what to do now. Should I try to return it to the original wiring? I was giving a box containing the original e-stop electro-mechanical switch PLUS another similar looking ancient device that with 3 coils on. But I have no clue what this is or where it should be located in the machine and I don't know if the device was removed because it no longer worked properly.
If there is anyone who knows about these lovely old Bantams, I'd really appreciate some advice. I'm a mechanical engineer and whilst I know a little about electrical stuff, this one has me stumped. Any positive comments would be greatly appreciated .
|Ian McVickers||11/01/2020 16:18:26|
|174 forum posts|
Some photos will help to see whats going on. So the lathe start stop is still operated by the sliding lever on the front of the lathe which operates the built in contactor? Looks like the Clarke inverter does not have any interface for controls at all and just outputs straight power allowing for a contactor to be placed between the inverter and the motor. If this is the case then you could replace the cover and foot pedal switches and an estop switch in the supply line to the contactor but its a bit rough and ready and wouldn't be my preferred option. If your going to keep the lathe it might be worth while changing the motor to a 3 phase 230v and getting a single to three phase vfd to run it. Then you could refit the switches and add any other controls you like in circuit.
This is what I did to mine as the original wiring was crap. I now have all controls in one place.
|1450 forum posts|
Some pictures of the parts with the 3 coils may help identify what they are for, perhaps they are not parts for your Bantam.
The original starting and stopping arrangement does have issues if not set up correctly but has the bonus of providing almost instant arrest of the chuck and any material being held in it if the need arises.
The controls shown in Ian's picture are fine but for me they would not be within reach if I was cranking a long drill or reamer into the work using the tailstock so unable to stop the machine in an emergency, unless there is a stop button/switch not in shot.
|Ian McVickers||11/01/2020 17:18:11|
|174 forum posts|
Emgee the foot bar with an estop is still fitted to the machine so can be hit from anywhere in front of the machine.
|noel shelley||11/01/2020 18:02:45|
|90 forum posts|
Hi Nick the 3 coils sound like the guts of a contactor.
Good luck Noel
|Nick Plumb 1||14/01/2020 16:35:38|
|3 forum posts|
The phase inverter converts 220-240V single phase to 415V 3 phase and whilst I've not run it extensively is runs forward. There is a selector switch on the e-stop box on the front low down. This turns it on and selects either the blue or red speed range. So to my mechanical engineer way of thinking. All should run properly were in not for the absence of the e-stop and butchered wiring. I very much like what Ian has done and that is the way to go I think. Hope to be able to run it on the phase inverter. So will consult and research further. I'd post some pictures but can't for the life of me figure out how to do it on this forum. Once again thanks for the help.
|358 forum posts|
Nick, PM sent
|not done it yet||14/01/2020 17:34:40|
|4507 forum posts|
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