3 Phase motor wiring - help please

[jimboallen]

Hi, Sorry i'm new to the forum so I hope this hasn't been discussed before.

I have just brought a second hand 3 phase motor connected to a hydraulic pump, unfortunately the plug has been cut off so i'm unsure of which wires do what.

There are 3 wires in the junction box and an earth, so 4 in all. I am assuming its a 3 phase motor not 2 phase??? do you get 2 phase motors?

Below is a picture to help, i would like to know which wire goes to where.

Thanks in advance

James

 

[telectrix]

i am assuming that the black cables on the right side of your pic. are the incoming from the plug. if so, connect the 3 blacks to L1,L2,L3, on a 3 phase 4 pin plug. connect earth to earth terminal. try it. if motor runs backwards, swap any 2 phase over.

 

[davelerave]

seems to be 3-phase star connected alright

i assume you're going to need starter+overload for this

check your direction as said and you can read the FLA off nameplate

 

[jimboallen]

Thanks Telectrix thats exactly what i was hoping!

Next question if you dont mind, what cable would I need to run 30m, options are ideally 4 core x 1.5mm, 2.5mm or 6mm as thats what I have available. Name plate is attached, cant see an FLA on there though dave?

Thanks

 

[silva.foxx]

Nameplate states: under the 50Hz spec;

1.5kw
400v Y
3.7A (FLA)
1400rpm

You'd have to calculate the run with regard to volt drop, etc...
I'd probably go 1.5mm...

.

 

[davelerave]

you won't drop much on a 1.5sq 30mt run anyhow-it's only a few volts at FLA ,and up to about 5% at most for startup

you can check supply voltage and total VD to be sure

 

[SirKit Breaker]

Drop the pump off just in case the motor runs in reverse, i know of some pumps which have been destroyed when this happens.