Help with motor from old grain mill

[Baffledron]

Hi,

Recently I bought a on old grain mill (c.1960) as a restoration project. The mill itself just needs a clean up and a couple of bearings to be replaced.

It's run from an old Newman electric motor, I'm guessing from its size (500mm overall length and weighs a ton) that it's about 5hp or 7.5hp. I'm guessing because the motor id/spec plate is not present (the rivet holes are though).

This is why I'm here!!

When I bought the mill it was already wired up to a DOL switch (MEM 252 ALS) and an isolator with a mixture of T&E, 3 core armour and 4 core armour. The chap I bought it from was selling it for his mother and he had never seen it running.

In my work as a joiner I've occasionally had to repair/service the single and three phase motors on my machines, but without the id plate I'm not sure what the motor on the mill is.

Presumably it's single phase, there's no capacitor so is it a split phase type?

You can see from the photos of the connector block on the motor that I've cut the connecting wires (red, black, yellow). The four labelled terminals are A1 A2 A3 and A4.

From the photos can any of you knowledgeable folk tell me more about it?

Is there a Newman Industries database archive?

Any help would be much appreciated.

Thanks

Ron

 

[Geoff1946]

Why do you think it's single phase? Is three phase present in the building? What does the starter you mention look like, (internally)?

 

[Baffledron]

Why do you think it's single phase? Is three phase present in the building? What does the starter you mention look like, (internally)?

Hi,

Whoever disconected the machine had left a length of T&E going to the isolator box. The connections to the terminal box of the motor (see photos) are just 2 wires (red and black). Presumably it was a single phase installation by the person who wired it up in its previous location. The starter is an MEM 252 ALS which is a single phase starter.

Cheers

Ron

 

[Andy™]

Why do you think it's single phase? Is three phase present in the building? What does the starter you mention look like, (internally)?

those connections do look like single phase

doubt its 7.5hp. even 5hp would be a push for single phase. youd be looking at 3kw (4hp) max on single phase usually

 

[Fleeting]

I agree the links suggest single phase. How many wires terminate at the terminal posts, eight?

 

[Baffledron]

Hi and thanks,

Attached is a photo of the isolator/DOL (as I got it).

Also attached is a photo of the motor terminals showing the 8 wires which come from the inside of the motor. Each wire has a label on it, some are a bit faded, these I've shown with the yellow lines. The terminal numbers are labelled in yellow.

Does this help to tell more about what the motor is?

Thanks

Ron

 

[David R Connell]

To me, this looks like a 3Phase isolator and starter the MEM starter number is a 3PH starter I'm from the 60s. Also, the Newman motor looks to me to be a 3PH motor that can run in star or delta. How this motor ever ran without a capacitor I do not want to guess or imagine running a 3PH motor on a single PH supply (with a capacitor) the power is reduced to 2/3rd of its 3PH capacity. You mentioned that the motor could be 5HP or a 7.5HP if this motor ever ran as a single PH motor I'm guessing the output required to run the mill must have been quite low because of the drop in output power something you will have to find out. As someone has already asked is there 3PH in the building if so, that is the road you need to go down in my humble opinion. Doing that, you need to match the motor to load requirements which you will have to work out. I can understand why the son has never seen it running.

 

[Fleeting]

To me, this looks like a 3Phase isolator and starter the MEM starter number is a 3PH starter I'm from the 60s. Also, the Newman motor looks to me to be a 3PH motor that can run in star or delta. How this motor ever ran without a capacitor I do not want to guess or imagine running a 3PH motor on a single PH supply (with a capacitor) the power is reduced to 2/3rd of its 3PH capacity. You mentioned that the motor could be 5HP or a 7.5HP if this motor ever ran as a single PH motor I'm guessing the output required to run the mill must have been quite low because of the drop in output power something you will have to find out. As someone has already asked is there 3PH in the building if so, that is the road you need to go down in my humble opinion. Doing that, you need to match the motor to load requirements which you will have to work out. I can understand why the son has never seen it running.

A split phase motor does not require a capacitor.

 

[Unicorn]

My tuppence worth:
I agreed with David R Connell in that it look like 3 phase with the links being for star or delta.
Its a 3 phase starter, a 3 phase isolator and if you look at the left hand side of Jpeg 8181 you can see RYB coming into the isolator on a bit of SWA.

 

[Baffledron]

Interesting...there are 8 wires at the motor terminal block.

If it's 3 phase, what are they for?
If it is single phase then what are they for?

It would be good if we could establish whether it is single or 3 phase.

Ron

 

[Fleeting]

My tuppence worth:
I agreed with David R Connell in that it look like 3 phase with the links being for star or delta.
Its a 3 phase starter, a 3 phase isolator and if you look at the left hand side of Jpeg 8181 you can see RYB coming into the isolator on a bit of SWA.

How do those links look three phase.

 

[Fleeting]

Interesting...there are 8 wires at the motor terminal block.

If it's 3 phase, what are they for?
If it is single phase then what are they for?

It would be good if we could establish whether it is single or 3 phase.

Ron

I suspect the eight wires are the ends of four windings for a dual voltage single phase motor but that is speculation.

 

[Unicorn]

How do those links look three phase.

 

[Geoff1946]

Have you got a resistance meter, e.g. an AVO or even a cheapo multimeter?

If you are happy to disconnect all the terminals measure the resistance between each one and every other one, if you understand me. It may then become evident how many windings there are and any hidden interconnections. DO NOT mix them up though. Make sure you can return it to present state then at least you wouldn't be going backwards!

You may find they are all in pairs, or whatever results may be clues to its form.

IF (BIG IF!) it's single phase there could be a centrifugal switch ?

The only other approach is to take it apart and see what the inside reveals. That could be a good idea anyway to clean and lubricate it.

You should also do an insulation test before any attempt to power it up.

 

[Unicorn]

I suspect the eight wires are the ends of four windings for a dual voltage single phase motor but that is speculation.

Yip could be, but why the 3 phase isolator and starter???

 

[Andy™]

View attachment 13289

er.. no. youll see there's only 2 links on the left & centre. there's none on the right. there's also not a cable connected to one of the terminals...

 

[Andy™]

Yip could be, but why the 3 phase isolator and starter???

because you dont usually get a single phase starter... you just use a 3 phase one...

 

[Andy™]

How do those links look three phase.

no comment... dont think he'd like my answer

 

[Fleeting]

View attachment 13289

Those links are for a three phase motor, the links in the OPs pics are typical of a single phase connection.

 

[Old Timer]

@Fleeting is correct, thats a single phase motor and probably split phase - and could be dual voltage as in the old days a lot of farms just had 2 phases

Anyone who thinks that is a 3 phase motor is a complete twat who shouldnt play with either 3 phase or motors......

The only way to tell the connections are to measure the resistance of all the wires etc by disconnecting the links and working it out with a drawing - thats a drawing you make yourself and not one you google - But remember where they were place by marking them before you lift them as if its the ends of the windings they are starts and finishes and wired up wrong and it wont work...

Fleetings scenarios of all winding wires brought out is the probable scenario yet i have never seen one labelled K, normally its A's, B's, U's & Z's with T (or K) for temperature sensing and then there would be 2 labelled this and never normally seen in an old motor like this