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Newlec starter switch wiring

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Good Afternoon All,

I have just bought second had elderly lathe off eBay.co.uk. It is fitted with a single phase motor and all works OK except the red "off" button on the Newlec starter switch does not function. I would like to rectify this. It is wired up with the live feed into T1 connection. I am wondering if the previous owner wired it up wrong.

Can anybody supply a wiring diagram please?

I will try and upload a picture of the inside of the switch.

Thanks in advance.

IMG_0518 (1).jpg
 
it's just possible that the lathe originally had a 3 phase motor and someone has replaced with a single phase unit, making a cock-up of modifying the starter. the label seems to indicate 400V for the control circuit.
 
If as mentioned the contactor coil is 400v then you cannot correct what is a mess up of the wiring, if however the coil is 230/240v ac then its just a matter of altering the wiring, be very careful here, the purple wire is taken of the live side of the isolating switch and can be dangerous if you are unsure of what you are doing here, ensure you have disconnected the whole unit further upstream and not just by the rotary switch on the front.

So to recap -
-The wiring is totally wrong, the overload won't cut the power if it operated and explains why the stop doesn't work.
-The coil on the contactor is possibly the wrong rating
-The wiring poses a hazard if not isolated properly upstream of the unit
 
If as mentioned the contactor coil is 400v then you cannot correct what is a mess up of the wiring, if however the coil is 230/240v ac then its just a matter of altering the wiring, be very careful here, the purple wire is taken of the live side of the isolating switch and can be dangerous if you are unsure of what you are doing here, ensure you have disconnected the whole unit further upstream and not just by the rotary switch on the front.

So to recap -
-The wiring is totally wrong, the overload won't cut the power if it operated and explains why the stop doesn't work.
-The coil on the contactor is possibly the wrong rating
-The wiring poses a hazard if not isolated properly upstream of the unit
Very many thanks Darkwood. I think Telectrix said it all, for the cost, buy a new unit and bin the old one. It's not worth the risk.

Thank you all for your advice, it's very much appreciated.
 
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Mate I wouldn't buy a new unit if the coil is 230V - 240V which I suspect it is as I'm pretty sure I've used that model on single phase before. If the coil has the correct voltage then all you need to do is connect it up correctly and it should work. As darkwood says isolate upstream due to that silly purple cable.
 
5his is for a 3 phase starter, but can be used on single phase using 2 of the poles for L and N.

direct-online-starter-dol..png


ignore the remote stops in above. the yellow wire would go to N if you have a 240V coil.
 
Mate I wouldn't buy a new unit if the coil is 230V - 240V which I suspect it is as I'm pretty sure I've used that model on single phase before. If the coil has the correct voltage then all you need to do is connect it up correctly and it should work. As darkwood says isolate upstream due to that silly purple cable.
Thanks Sintra, I take your point which brings me back to my original question, how do I find a wiring diagram to start from scratch.
 
How did we all manage before the internet?

we had more time to work it out with those funny obsolete tools called pencils.
 
What size motor is the starter protecting? looks like the purple wire is a short to remove the overload contacts from the circuit. Possibly the overload was set too weak or it has failed. The coil voltage is usually written on the coil of this unit.
IE The motor has overloaded and the overload would not reset or it was set too low causing constant overloading. Therefore somebody "fixed it" in a dangerous way by adding the purple link.
Please check the motor size to see what the full load amps are or post a photo of the plate.

ps did you notice the nipped cable?

dol.png
 
What size motor is the starter protecting? looks like the purple wire is a short to remove the overload contacts from the circuit. Possibly the overload was set too weak or it has failed. The coil voltage is usually written on the coil of this unit.
IE The motor has overloaded and the overload would not reset or it was set too low causing constant overloading. Therefore somebody "fixed it" in a dangerous way by adding the purple link.
Please check the motor size to see what the full load amps are or post a photo of the plate.

ps did you notice the nipped cable?

View attachment 34879
I have had a good look at the motor but there is no plate or information on it. I was told it had been rewound recently to single phase (at vast expense). The motor is big! 25cm across!

I have installed another starter switch, I had in stock. A normal single phase unit, the same as on my single phase four post car lift. But the lathe will not run using that switch. So I don't know.
 
Can you link me to the lathe on ebay or if its not there now give me the lathe details. There may be a plate on the lathe?

Are you running this on a 13A plug top?

In France we do not have fused plugs, just individual circuits for each socket. This circuit is fixed at 16 amps and does not seemed bothered by the load. The lathe is a 1940 Colchester Master. I will take some photos a bit later this evening.
 
In France we do not have fused plugs, just individual circuits for each socket. This circuit is fixed at 16 amps and does not seemed bothered by the load. The lathe is a 1940 Colchester Master. I will take some photos a bit later this evening.
mykey: photos as promised. When advertised on eBay she did look rough. I have since serviced it, given it a coat of paint and plenty of oil in the right places. It's just that starter switch that I would like to get right.

Colchester Master 1940.jpg


Colchester motor.jpg
 
Whithout a motor plate you are kinda buggered tbh, as its been rewound it may be a idea to try trace the company that did it and see if they can tell you its rating etc, if you cannot trace this then see if the motor has a thermal trip or thermistor in it and ensure you use this as a backup protection .. if we were to assume the old overload was rated for the motor when it was a 3ph then it may have been a 2.2kw or a 3kw judging by the range on it, if this was rewind to a single phase then we could expect it to be rated the same but the current will be approx x3 so we would be looking at a 6.5 - 9amp FLC rating ... running the machine and clamping it in its heaviest gear will give an idea where abouts we sit with the actual rating of the motor but again I stress we are making a guess based on a presumption. Your motor is required to be protected from overload so you need to achieve this somehow with protection design for motors.

You could always look up the original lathe 3ph motor rating and work it from there.
 
Whithout a motor plate you are kinda buggered tbh, as its been rewound it may be a idea to try trace the company that did it and see if they can tell you its rating etc, if you cannot trace this then see if the motor has a thermal trip or thermistor in it and ensure you use this as a backup protection .. if we were to assume the old overload was rated for the motor when it was a 3ph then it may have been a 2.2kw or a 3kw judging by the range on it, if this was rewind to a single phase then we could expect it to be rated the same but the current will be approx x3 so we would be looking at a 6.5 - 9amp FLC rating ... running the machine and clamping it in its heaviest gear will give an idea where abouts we sit with the actual rating of the motor but again I stress we are making a guess based on a presumption. Your motor is required to be protected from overload so you need to achieve this somehow with protection design for motors.

You could always look up the original lathe 3ph motor rating and work it from there.

I tracked down a users handbook for this model and it states " The standard motor is 1. 1/2 H.P. 2-phase or 3-phase, but D.C. and Single phase motors are fitted to order at extra cost..."

I am wondering if it might be better to start from scratch, buy a 1. 1/2 H.P. single phase motor and fit a new matching starter switch.
 

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