Replacement switch/ Motor Issue!?

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Chris152

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Might it be possible to get a replacement switch to fit the mount on the motor of my Sorby RS2, pic attached? It's about 20 years old, I think.
_MG_0197.jpg
 
I bought a very similar switch from a seller on amazon recently to replace one on an Axminster planer of similar age. If you check the codes printed on the body of the switch there should be plenty of choice, just watch the rated current as they do vary.
 
Thanks Tris. I'm searching but not finding!

What are the important bits of code? When I type the lot in, I get all kinds of stuff but not a switch.
 
This one?
link
Various current versions seem to be available. Your original looks like 8A - this one is 10A
That certainly looks the part. But the details say it's only 25mm wide, but 43mm deep, which doesn't look right in the pics. Mine's a 55mm wide plate, and 35mm across the raised bit with the switches. I'm assuming it's important to get 8A rather than 10? I don't actually use the switch, it's just left on and I control the lathe through the VFD.
 
10a is heavier than 8a so shouldn't matter. I assume you need it for the emergency "off" - if not just connect the wiring and blank it off.
Funny thing is, a friend connected the wires using the switch connectors (there's a male spade on the same terminal as the screwed in ones - sorry for the wrong terms! - which means live now connects to live, neutral to neutral) this morning, motor running great, very happy. So I decided to finish the piece I started before the problem, and after about 10 secs of trying to turn and getting no cut I realised it's running in reverse! ha, bizarre. I've read around a bit online and it seems with 3ph, you reverse two wires to achieve this effect. But as far as we can tell, we didn't reverse any wires. live to live, neutral to neutral.
I think I need to find an online electrics course for idiots.
I'll post a pic of what I have now in a mo
 
The live connects to live (brown to red, out of sight) the same way as blue to black which you can see clearly:
_MG_0199.jpg

Why would this cause the motor to reverse?!

ETA - before switching the wires, the brown and black wires occupied the top positions; in order to connect live to live, the brown had to drop to the lower position, blue came up to join with the black, as in this pic.
 
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Should I be connecting the neutrals to the lives?

eta - just found this!
_MG_0200.jpg

Does that mean I can just switch the positions of the two we moved, so in the switch brown now joins black and blue joins red?
 
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The answer to that one is 'yes'. Switched the leads and it turned the correct way.

But - while it runs perfectly smoothly at all speeds in reverse, turning the correct direction is stutters once it reaches the top 25% of speed.
Any thoughts what may be causing this? Clearly it's not the switch.
 
Anyone?! I really want to get using the lathe again but can't!
Why would the motor run smoothly turning in one direction, but stutter at higher speeds in the other direction?
I can't think of anything beyond the motor that would cause it to happen.
 
Not familiar with this equipment but just looking at comments and pics.Is it possible that as part of the "rewire" you have isolated out your dc motor supply and are feeding with mains ac power. Motor will still work but may explain symptoms
 
Anyone?! I really want to get using the lathe again but can't!
Why would the motor run smoothly turning in one direction, but stutter at higher speeds in the other direction?
I can't think of anything beyond the motor that would cause it to happen.
Is there not a forward/reverse switch?
 
Thanks for the reply, Tom - I know nothing about electronics, but as far as I can tell all we've done is bypass the switch on the motor. And the result is that the motor is behaving exactly as it did before we bypassed the switch. Except that we now know, as a result of switching the red/ black connections, that it works perfectly in reverse. :unsure:
 
I would suspect a fault in the motor, as long as you’ve eliminated downstream mechanical issues.
 
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No click as the motor comes to a stop, guineafowl. I've no idea about a centrifugal switch, but just had an online read - apparently they're on single and split phase motors, I was just assuming mine's 3 phase? I don't know if the above photo of the info plate tells you that?
Thanks
 
No click as the motor comes to a stop, guineafowl. I've no idea about a centrifugal switch, but just had an online read - apparently they're on single and split phase motors, I was just assuming mine's 3 phase? I don't know if the above photo of the info plate tells you that?
Thanks
Sorry, I edited my reply - got confused with another thread that is dealing with an AC motor. Yours is DC (not three phase) and there will be no centrifugal switch.
 
Sorry, I edited my reply - got confused with another thread that is dealing with an AC motor. Yours is DC (not three phase) and there will be no centrifugal switch.
Thanks guineafowl - I'm also harranging the good people over on AAW with this problem and they've established it's DC and therefore not a VFC but a converter with speed control (Dart). I had no idea. Seems like it might be the brushes? I thought it had none, but that's based on complete ignorance.
In order to keep the thread thrilling for everyone, I've made a vid of the motor running as I wind up the speed:

eta - sorry John, just saw yours. It's a Dart controller. Some of the discussion on AAW is whether the state of that's at issue or not.
 

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