Starters and motors

[i=p/u]

was looking at a motor the other day and when I measured across all I got was 230v to Earth but not 400v between.

 

[i=p/u]

Rating ate.

 

[i=p/u]

What's this?

 

[davesparks]

View attachment 27775What's this?

A PCB with some wires connected to it.

 

[Pete999]

was looking at a motor the other day and when I measured across all I got was 230v to Earth but not 400v between.

Across what and between what?

 

[Darkwood]

What controls the motor? .... DOL, VSD, Star/Delta, Soft Start etc etc?
Has it got speed control?
What meter are you using to get your voltage?
What's the nature of this post... is something wrong with the motor or its operation?

 

[D Skelton]

The links are arranged in star formation. If you measure between each incoming phase to the star point of course you're only going to get 230V. That is of course assuming direct connection to the supply. What voltage are you getting between the incoming phase terminals? How is the motor started?

 

[ipf]

View attachment 27774Rating ate.

Did it taste good?

 

[i=p/u]

Ate screws and all.. Ipf

 

[i=p/u]

What controls the motor? .... DOL, VSD, Star/Delta, Soft Start etc etc?
Has it got speed control?
What meter are you using to get your voltage?
What's the nature of this post... is something wrong with the motor or its operation?

I know nothing about controls and motors. I measured 400v at isolator , which then goes to id say is a starter of some sort (pic). I then measured 230v at motor housing. I used martingale gs38 tester

 

[VoltzElectrical]

I know nothing about controls and motors.

Neither do I, that's why I leave it to others!

 

[davesparks]

I know nothing about controls and motors.

Then leave it alone and advise your client to hire someone who does

 

[baldsparkies]

I know nothing about controls and motors.

Sorry, but having said that !!
What exactly are you trying to achieve here ??
I think you should put that cover back on to be honest and get someone with you who does know about motors and control gear.

 

[i=p/u]

Guys and divas , I only check power at devices after that the boss sends it back for specialist which I asumme in this case is an electrical engineer .

 

[i=p/u]

Haven't even told you about the caretaker and your telling me to put cover on lol.

 

[i=p/u]

Neither do I, that's why I leave it to others!

Agree totally

 

[Marvo]

If it's supplied by a variable frequency drive there's a good chance your tester won't be able to make sense of the supply at the motor due to the high carrier/switching frequencies.

 

[i=p/u]

Is that not a drive in the pic Marvi

 

[Marvo]

I wasn't entirely sure what that was in the pic. Have you got another pic taken from a bit further away?

 

[i=p/u]

If it's supplied by a variable frequency drive there's a good chance your tester won't be able to make sense of the supply at the motor due to the high carrier/switching frequencies.

I measured 230v at all points on motor to earth but nothing between connections

 

[Marvo]

Was the motor running?

 

[davesparks]

Guys and divas , I only check power at devices after that the boss sends it back for specialist which I asumme in this case is an electrical engineer .

If you don't understand the basics of motor control then how do you know what you are testing for or what test equipment is appropriate/safe to use?

 

[i=p/u]

Dave not my job now so fuk it . Just a little interested .

 

[elevate]

Its not a drive in the picture, the circuit board looks like some sort of RC circuit, could be for soft start or noise suppression. Any wiring diagrams?

 

[i=p/u]

And out of interest its a band saw. With two emergency stops onit plus start stop button

 

[Marvo]

It's not a drive and it's a bit elaborate for a suppression board plus there's no ground on it. Maybe soft start but I can only see 2x components on the heat sink so also unlikely.

You didn't say if the motor was running or not. What was the fault they reported and what was the application or machine it was a part of?

 

[Silly Sausage]

View attachment 27778 Dave not my job now so fuk it . Just a little interested .

Who pulled all the inards out?

 

[Marvo]

My tying is too slow, it's probably the control board for the interlocks / estop etc. In that case the motor looks like it's direct on line so I give up about your weird test results in that case.

 

[i=p/u]

The fault was bandsaw not working. It also has a dust extractor tapped off it

 

[i=p/u]

But as said why only getting 230v motor connections,

why nit not just break live with e stops , forget control boards ...