Star delta fan wiring help please

Goldygoldy · Jul 23, 2015

Hello there

have been asked to fault find on a clients 3 phase star delta fain in a grain store.

the client purchased the fan second hand and I have power across the contractors but no power on the out going side.

no wiring diagrams either.

Can anybody give me some in what to check for and a website for a wiring diagram would be great (already googled it)

thanks in advance

shanky887614 · Jul 23, 2015

Goldygoldy said:
Hello there

have been asked to fault find on a clients 3 phase star delta fain in a grain store.

the client purchased the fan second hand and I have power across the contractors but no power on the out going side.

no wiring diagrams either.

Can anybody give me some in what to check for and a website for a wiring diagram would be great (already googled it)

thanks in advance

obvious question first, have you checked the fuses

Goldygoldy · Jul 23, 2015

I didn't check them no, there's been some cables just cut at the bottom
RHS of the control box (t5) like I said there is power at contractors.

just strange why some cables have been cut

Guest77 · Jul 23, 2015

Goldygoldy said:
Hello there

have been asked to fault find on a clients 3 phase star delta fain in a grain store.

the client purchased the fan second hand and I have power across the contractors but no power on the out going side.

no wiring diagrams either.

Can anybody give me some in what to check for and a website for a wiring diagram would be great (already googled it)

thanks in advance

Have you inspected the start stop system to se if there is a wire loose or a line fuse blown, or a stop button pressed in?

Darkwood · Jul 23, 2015

Hi Goldy - welcome to the forum

A few questions first :-

- Have you any experience with motors and control systems?
- If your self employed have you expressed to your insurance you are working on such equipment otherwise you may only be insured for single phase installs.
- can you take a photo front on so we can see the cut wires and where they are connected to or where they might have gone.
- what happened to the previous fan - the issue that led to its failure may be present still.

Be very careful here unless you are competent in such systems you shouldn't really get involved with them without supervision, a simple mistake with such a sized fan can have costly results, its sometimes better to be honest than get involved with equipment you have no knowledge of :thinking:

Goldygoldy · Jul 23, 2015

darkwood said:
Hi Goldy - welcome to the forum

A few questions first :-

- Have you any experience with motors and control systems?
- If your self employed have you expressed to your insurance you are working on such equipment otherwise you may only be insured for single phase installs.
- can you take a photo front on so we can see the cut wires and where they are connected to or where they might have gone.
- what happened to the previous fan - the issue that led to its failure may be present still.

Be very careful here unless you are competent in such systems you shouldn't really get involved with them without supervision, a simple mistake with such a sized fan can have costly results, its sometimes better to be honest than get involved with equipment you have no knowledge of :thinking:

Thanks for the reply...
i do have experience although along time ago I used to maintain air handling units for sainsburys
im also insured for three phase working

i have left the site now however the cut wires look as if they was in terminals 97 and 98 just below the first contractor.

the previous fans shaft went on it so they replaced it with this new one.
The new fan already came with the control box

Darkwood · Jul 23, 2015

Goldygoldy said:
Thanks for the reply...
i do have experience although along time ago I used to maintain air handling units for sainsburys
im also insured for three phase working

i have left the site now however the cut wires look as if they was in terminals 97 and 98 just below the first contractor.

the previous fans shaft went on it so they replaced it with this new one.
The new fan already came with the control box

That's fine.. just checking we haven't got a domestic brigade stepping into areas he shouldn't be in ...

Thats sorted now - the wires that may have been in 97 an 98 are usually signal wires to operate maybe a trip lamp, buzzer, relay etc anything that may have operated if the overload tripped basically.

Now back to the starter, do you get any operation of the star/deta contactor when you press the start button?
cf1 and cf2 are your fuses for the 400v control circuit are these both good, if not then you need to figure out why one or both have blown - you could follow the control cables through the start/stop button etc and just check for flash marks or damaged/loose wires.

Ask the customer the history behind having to buy a new fan, it may be the case it was mis-diagnosed and in fact the controls were faulty.

JD6400 · Jul 23, 2015

Hi Goldy , could you post more detailed photo's ?
At the moment I would guess that they are part of a remote start setup , but a guess is all it is without more detailed photo's .

And Darkwood is not scaremongering with his advise about it getting costly , it looks like you have a Brooke Cromton 18kw stand alone starter there . Those contactors are now obsoleat , and a replacement unit will be around £400 +vat