Fitting dol contactor for 415 v3 phase fans

[seadog60]

I have to fit dol contactor for 415v 3phase fans where the contactor must switch at 110volt how is this done please.

 

[Dayo]

why must it switch at 110 volt?

 

[johnboy6083]

you need a contactor with a 110v coil

try this Contactors 110V Coil Control Voltage

 

[johnboy6083]

why must it switch at 110 volt?

on the systems im working on at the mo, all controls in the panel are 110v, and all plc controls are 24v

 

[seadog60]

Jonnyboy how does the 415v reduce to 110v with just fitting a coil.Thanks

 

[johnboy6083]

when you said that it needs to swich at 110v, i thought you meant that that was your coil voltage. can you clarify what type of work your doing, and what control gear already exists?

john

 

[Dayo]

seadog, why is it switching at 110 volt?

 

[seadog60]

I am fitting 2 new extraction 3 phase fans and on the specification the dol contactors must switch at 110v as i have not fit anything yet what would be the best way to do it

 

[Dayo]

where is the job then industrial? who did the spec?

 

[seadog60]

Yes it's industrial no idea who did the spec but it states that it is a regulation it must be 110v

 

[Dayo]

have you got a layout of dol starter emergency stops etc, or is the start / stop at one point

 

[Dayo]

the 110 volt is probably for safety if remote stop buttons or remote emergency stop buttons are required

 

[malcolmsanford]

There must be some sort of TX in the circuitry, but as jonny said a few posts ago are you sure it's not 110v control voltage.

 

[seadog60]

Thanks guys i shall have to have a look again at the spec as it could be that malcolm but i seemed certain it said it had to be 110v on the stop start for safety

 

[Dayo]

only if its remote from the start stop unit otherwise i would just use 415 volt coil, as there is no need for 110 volt

 

[seadog60]

Dayo it has just the start stop

 

[seadog60]

Sorry just the 0ne start stop

 

[Dayo]

well you can get away with a 415 volt dol unit but you will have to state you are not using 110 volt to cover yourself.
you would have to use a transformer to step down from 415 or 230 to 110 volts then this 110 volts is your control voltage powering the contactor coil via start stop & emergency stop buttons. if they wanted remote stop buttons in the future it may not be safe to run 415volt cables in the industrial unit

 

[seadog60]

Thanks Dayo is there a regulation that states it must be 110v because i haven't read it?

 

[Dayo]

no most coils controlling motor / fans are the same voltage as the motor / fan they are controlling especially when there is only one start stop unit.
if you think about it there is one cable coming in to the dol starter and one cable leaving, both are carrying 415 volts 3 phase