Re-wiring Sprecher + Schuh 15hp Starter Box

[DeanBayley]

Hi Guys,

 

I'm trying to re-wire a Wye-delta open transition 3-phase motor starter...

 

Here is the box

 

And here is the motorbox

 

I have a very limited knowledge of motor starters, everything i know i've learned in the last few days of googling...

 

As you can see someone has been playing with this and they have left some wires hanging that have no obvious home..

 

Also please can you check the second picture of the motor box, i've labeled the terminals in white, have i got them right?

 

Any pointers would be greatly appreciated..

 

Dean.

[kana]

Hi Dean,

 

In the starter box, the 3 black cables terminated are the motor cables. Looks like the 2 red (marked) cables are terminated from the main contactor (C1) normally open contact. I'm not sure about the other red (unmarked) cable. It's best if you get a schematic diagram of the control circuit to guide you.

 

The 6 wires from the starter should be connected at the motor terminal in the following manner:

U1 - Red 1

W2 - Red 2

 

W1 - Yellow 1

V2 - Yellow 2

 

V1 - Blue 1

U2 - Blue 2

 

 

 

 

Regards,

Kana

 

 

[DeanBayley]

Hi Dean,

 

In the starter box, the 3 black cables terminated are the motor cables. Looks like the 2 red (marked) cables are terminated from the main contactor (C1) normally open contact. I'm not sure about the other red (unmarked) cable. It's best if you get a schematic diagram of the control circuit to guide you.

 

The 6 wires from the starter should be connected at the motor terminal in the following manner:

U1 - Red 1

W2 - Red 2

 

W1 - Yellow 1

V2 - Yellow 2

 

V1 - Blue 1

U2 - Blue 2

 

 

 

 

Regards,

Kana

 

But surely that would mean that the overload relay wasn't being utilised?

 

What are U3, V3 & W3 for?

 

Dean.

[kana]

Hi,

 

I was referring to the motorbox and not the terminal blocks in the starter board when i wrote this.

U1 - Red 1

W2 - Red 2

 

W1 - Yellow 1

V2 - Yellow 2

 

V1 - Blue 1

U2 - Blue 2

 

That's right the overload relay is not being utilised. The motor wires from C1 must be connected to the overload and then to the terminal block. I don't see a use for the U3, V3 & W3 terminal blocks. Have you got the schematic diagram?

 

Regards,

Kana

[marke]

Hello Dean

 

Welcome to the forum.

 

Have a look at http://www.lmphotonics.com/star_delta.htm

 

If you look at your starter, you can easily identify the star contactor (KM1), it has links across one side and is the left hand contactor in your photograph.

KM2 is the center contactor and KM3 is the right hand contactor.

 

The incomming three phase supply is connected to the top of KM2 and KM3 where the blue links are.

 

One end of the motor windings are connected to the thermal overload and the other end of the motor windings are connected to the bottom of KM3.

 

In the motor box, one end of the windings is te top row, and the other end of the windings is the bottom row.

 

There is additional circuitry in the box, and it is not possible to trace that from the photograph. You could trace that out by hand and get a clue.

 

Best regards,

Mark.