3ph contactor

[Benny_Boy]

Afternoon chaps,

I've got a mate with a rather 2nd hand 3ph compressor he would like me to connect.

I don't do a great deal of commercial work as many of you who know me will know but I want to help him out and gain some experience along the way.

There's an old 3ph panel in his garage with 3x 32a bs3036 which Currently supplies a 3ph+n+e socket outlet in 4mm swa via a 20a 3ph mcb in its own housing.
The compressor has a 5.5kw motor.
I'm happy enough with Sph contactors but haven't a scoobys how this one needs to be connected to allow safe operation.

Can one of you friendly industrial chaps throw some light on it. (pic attached)
any info (or light) muchos appreciated.
Apart from the 6 obvious terminals I'm at a loss.

I await the flames!

cheers

 

[Knobhead]

Where abouts in Notts are you?

If you can pick me up I’ll show you how to do it.
Sorry but I can’t drive now.

Charge will be 2 pints of good bitter J

 

[silva.foxx]

That's a very generous offer by Tony... cheap at half the price!

First off... your 5.5kw motor will have an FLA rating of at least 10amps so that contactor and overload should be checked to ensure the overload can be set to the FLA. (It appears to be a 32A o/l but what's the lowest rating on the dial?)

Second... is the contactor coil voltage 240v or 415v (or other)?

And lastly... is the start stop on the front of the DOL housing, or are they remote? Where does that cable go?

.

 

[Benny_Boy]

No idea what voltage the coil is, I was hoping someone would have seen this particular chappie before.
I'm thinking a pm to tony may be the answer!!

 

[Engineer54]

No idea what voltage the coil is, I was hoping someone would have seen this particular chappie before.
I'm thinking a pm to tony may be the answer!!

Well, i don't think you'll find anyone better here, when it comes to motor controls Benny. Think yourself dammed lucky he's there on your doorstep too ..lol!!!

 

[Benny_Boy]

Well, i don't think you'll find anyone better here, when it comes to motor controls Benny. Think yourself dammed lucky he's there on your doorstep too ..lol!!!

I've PMd Tony, and am hoping the offer of 5pints may get him out! cheers eng

 

[Knobhead]

Have sent you my number Benny

 

[malcolmsanford]

What a great advert for this forum .....................always thought Tony was a gentleman, though must be a bit touched wanting to work on all that "proper" electrics.........

 

[Knobhead]

No plastering or making good, can’t beat it! I’m an artist with a jackhammer.
My last ten years were spent mainly on PLC control systems, great fun with the lunatic boss I had. I loved his reaction when we damaged a £.2M bit of kit “Oh well, sh*t happens”.

It’s each to his own J

 

[Knobhead]

Drawings sent J

 

[Benny_Boy]

You're a scholar and a gent Sir.

 

[cantabrian9]

didn,t you learn about 3 phase at TECH ?? Benny Boy? (we had them in the Falklands)

 

[Knobhead]

I learnt about domestic ring mains, cantabrian9. But never having any need of them I’ve never kept up to date with them. We all have our fields, the lads on this site can run rings around me when it comes to regulations regarding domestic installations.

We’re here to help each other!

 

[johnboy6083]

hear hear tony! nice to see a bit of humility ( i think thats the word)

 

[Knobhead]

It may be humility, but it’s also a straight statement of facts.

 

[Knobhead]

How did you go on with this ?

 

[Benny_Boy]

How did you go on with this ?

Ha, Well I went down the other day and the contactor was knackered. But he said "Don't worry, I was wired straight into that thing anyway" (pointing at the pressure switch).

I told him I wouldn't wire it up without OLP for the motor and he didn't want to pay for a new contactor, so I've left him with it!
No doubt he'll be cremating himself as we speak.

Thanks for your input Tony anyhow.

 

[Knobhead]

Some old compressors (and I mean old) did have three phase pressure switches. I’ve not seen one for years.

 

[Benny_Boy]

Some old compressors (and I mean old) did have three phase pressure switches. I’ve not seen one for years.

it was this type of jobbie but bigger, older, and more battered.

Air Compressor Pressure Switch 415v 3 phase | eBay UK

 

[Knobhead]

Oh well, so long as he knows there’s no O/L protection it’s up to him.

 

[jeffducati]

thats what i like about us all we are all willing to help and thats a genuine chap and two pints only you old softy!!!
any way another quick check is the actual wiring to to contactor if there is no neutral arouind then assume 230 usully around there on side or look at top the answer is there for stitching
but your problem is solved and you will learn something valuable