Starter switch problem-UPDATE-sorted.

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Mr Ed

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One for any electrical types;

The starter switch on my metalworking lathe has broken. The internals are made of bakelite and the piece that actuates the stop button has sheared off. Presently it will switch on, but not off, which is obviously not ideal.

Am I right in thinking that this is just an early NVR switch and could be replaced with a modern equivalent, or is there more to it than that?

3292694611_d8ce242e54.jpg


3293516086_90e9a3a9a1.jpg


Any advice gratefully received

Cheers, Ed
 
Forgive my ignorance, but whats the difference between a motor starter and an NVR switch?

It does say its a starter on the label inside it (just had another look)

Cheers, Ed
 
NVR or no volt release switch is simply on or off, a motor starter starts the motor and ramps up so that the motor doesn't use too many amps as it starts, really to avoid overloading circuits. Often motor staters can be used in conjunction with micro switches on guards and doors for safety.
 
Ed, I think your switch possibly includes an overload protector under the black knob with the lettering on it.

This is not a fuse type action but a thermal device that ignores start current surges but will trip on continuous overload and causes the NVR to drop out and not allow restarting until the device has cooled down.

I suspect you need a NVR with overload protection. Looking/asking for these keywords in conjunction with the max current draw of your motor should get you what you need.

hth

Bob
 
Thats what a motor starter is, if you look at the toolstation site they do them separately.
 
Oryxdesign":2ieq4cm8 said:
Thats what a motor starter is, if you look at the toolstation site they do them separately.

What you described sounded like a soft starter to me. I don't think this what Ed has.

I agree that toolstation DOL starter fitted with a thermal overload relay sould fit the bill.

Bob
 
The one I posted a link to is the same but comes fitted with adjustable overload. It is confusing as they get referred to by different names
 
Thanks Bob. No toolstation near here, but Machine Mart have one in stock the right size for £26 so I'll probably call in there today.

Cheers, Ed
 
OK, got a starter from Machine Mart, but the next question is how do I get from this;

3293516086_90e9a3a9a1_b.jpg


to this

3296617031_ccfae5e441_b.jpg


i.e. what terminals on the old one relate to those on the new.

I am sure someone will tell me to get an electrician, but with a small amount of advice I can do it myself hopefully.

Cheers, Ed
 
Look at the instructions for the new switch, I suspect 1 end will be the input and the other the output.

Read which needs to be L, N and Earth then just disconnect the cables from the old switch and put them in to the new, Brown = Live, Blue = Neutral and Green / Yellow = Earth in case you didn't know.
 
EdSutton":24jt77hy said:
OK, got a starter from Machine Mart, but the next question is how do I get from this;

3293516086_90e9a3a9a1_b.jpg


to this

3296617031_ccfae5e441_b.jpg


i.e. what terminals on the old one relate to those on the new.

I am sure someone will tell me to get an electrician, but with a small amount of advice I can do it myself hopefully.

Cheers, Ed

Hi Ed,

there is a train of thought that goes like this. If you have to ask you need to get someone in who knows!

However if you feel suitably competent to do the wiring, then the input power goes to any 2 of the three odd numbered terminals and the motor is connected to the matching (in line) even numbered terminals. Normally one would use L1-T1 and L2-T2.
All the earth wires should go to an earth terminal on the left hand side.

I'm mildly surprised the unit is marked 400v. This might be that the overload switch will work ok at up to 400 volt or you might have bought and NVR with a 400v coil in which case you have bought the wrong one.
The NVR coil must be designed for 240v single phase.

Connect up the input first. apply power and switch on the nvr. It should clunk once and hold in and not buzz more than just above audibility.
If it drops out when you let go of the start button or buzzes loudly, then you have the wrong one.

I think you got it from MM but their website does no show their product range of NVR so I can't judge if you have the right one

HTH
Bob
 
9fingers":3puib6id said:
I'm mildly surprised the unit is marked 400v. This might be that the overload switch will work ok at up to 400 volt or you might have bought and NVR with a 400v coil in which case you have bought the wrong one.
The NVR coil must be designed for 240v single phase.

Connect up the input first. apply power and switch on the nvr. It should clunk once and hold in and not buzz more than just above audibility.
If it drops out when you let go of the start button or buzzes loudly, then you have the wrong one.

I think you got it from MM but their website does no show their product range of NVR so I can't judge if you have the right one

HTH
Bob

I'm a bit concerned about the 6A rating as well!!
 
OllyK":3eqau1gi said:
9fingers":3eqau1gi said:
I'm mildly surprised the unit is marked 400v. This might be that the overload switch will work ok at up to 400 volt or you might have bought and NVR with a 400v coil in which case you have bought the wrong one.
The NVR coil must be designed for 240v single phase.

Connect up the input first. apply power and switch on the nvr. It should clunk once and hold in and not buzz more than just above audibility.
If it drops out when you let go of the start button or buzzes loudly, then you have the wrong one.

I think you got it from MM but their website does no show their product range of NVR so I can't judge if you have the right one

HTH
Bob



I'm a bit concerned about the 6A rating as well!!

Why is that Olly? Ed said his motor was rated at 4.5 amps? If it then draws sustained 6 amps, then there is something wrong and should trip.

Bob
 
Dont panic chaps, its wired up and works fine... :D

Thanks for the help.

Its apparently a starter that suits either single or three phase.

The motor is rated at 4.5 amps so its the right size switch.

Cheers, Ed
 
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