I have just purchased a Boxford Lathe

[Pete.]

The contactor and overload are separate usually. Disconnect the overload and the motor can be switched.

 

[123hotchef]

The contactor and overload are separate usually. Disconnect the overload and the motor can be switched.

I'll have a look

 

[123hotchef]

So it is I need to find a diagram for it maybe it's wired up wrong

 

[Richard.]

If your in there anyway I’d change the cap as well even if it’s not causing your problem they are cheap enough and makes sense to do it while your on. You want the uf value and spec the voltage above what your motor runs. Most are rated to 450v.

 

[123hotchef]

If your in there anyway I’d change the cap as well even if it’s not causing your problem they are cheap enough and makes sense to do it while your on. You want the uf value and spec the voltage above what your motor runs. Most are rated to 450v.

funny enough I have a new cap but that one is just fine I will mount it to the top of the motor though where it is suppose to be not with the cable threaded through the door hinges!

 

[123hotchef]

I think this overloader is not ratted high enough my motor draws 4.5 amps this appears to be 2.8

 

[Hopefuldave]

That could be a problem...
Looking at it, that may have been specced for a 3-phase motor, before the single-phase went in, they use a lower current but three times, so 2.8 amps is about right for an HP or so on 3-phase, and your 4.5 amps youre seeing on single.

Dave H
(the other one)

 

[Seadog]

Looking at it, that may have been specced for a 3-phase motor,

It is a 3-phase contactor, so precisely that reason.

 

[123hotchef]

It can be either that dol.
I presume I can just purchase a seperate overload and swap them over.

 

[Hopefuldave]

It is a 3-phase contactor, so precisely that reason.

Hard to find anything else rated for inductive loads, so most will use them for single-phase too!

Dave H. (the other one)

 

[Pete.]

You could see if you can isolate the neutral from the overload and put the feed through all three in parallel. That would effectively make it a 8a overload instead of 2.7a

 

[123hotchef]

You could see if you can isolate the neutral from the overload and put the feed through all three in parallel. That would effectively make it a 8a overload instead of 2.7a

that could work, so just use a chock block for the neutral and link the live through all 3 Live terminals I would need to alter the wiring of the actual DOL too 3 phase setup

 

[Pete.]

I dunno if it'll work or what hindrances there might be to it, It's just a suggestion. It looks like at the moment they have T2/L2 and T3/L3 wires in series. Dunno why that might be.

 

[123hotchef]

I dunno if it'll work or what hindrances there might be to it, It's just a suggestion. It looks like at the moment they have T2/L2 and T3/L3 wires in series. Dunno why that might be.

The destructions say it can be 1 phase or 3 phase the wire layout needs changing for each. It was also wired wrong according to the instructions but it still didn't change anything when I swapped them.about

 

[123hotchef]

thats the 3 phase set up single is different

 

[123hotchef]

what is the star delta starter? as it states only a max of 4.2 amps on that

 

[eLuSiVeMiTe]

what is the star delta starter? as it states only a max of 4.2 amps on that

Its when a motor is started in delta then switched to star after up to speed I belive.

 

[Hopefuldave]

Its when a motor is started in delta then switched to star after up to speed I belive.

Don't quote me on this, I think it's the other way around, to limit start-up current and torque on BIG motors - wound for delta on 415v, the star connection would need about 650 - 700 volts for full current, so the start current on 415 is reduced quite a bit, then once up to or close to speed it's switched to the delta connection and gets full (but not "locked-rotor" starting) current?

I must dig out my 1920's books on motors and starters....

Dave H. (the other one)

 

[Seadog]

Don't quote me on this, I think it's the other way around

I agree. The clue is in the name

 

[123hotchef]

I managed to find a overload switch in the 4 to 6 amp range 13 quid on eBay so I can just swap them over.