3 Phase Motors & Control Gear

[dldavies]

I am wiring 3 3 phase motors, 1.1 KW each via 3 STOP/START manual starters. If one starter locks out for any reason, the others also need to close down simultaneously.

I initially thought that I would have to have a relay in each starter connected in series but I've realised that won't achieve what I want.

The other alternative is to bring the supply into a contactor, then to the TP/N distribution board out to the starters but this would mean I believe that each starter from the auxiliary contact would have to be connected back to the contactor coil so that whichever motor locked out would open the contactor.

Is this correct?

Thanks in advance

 

[telectrix]

tony's your man here.

 

[Knobhead]

Do the drives start individually? It make a big difference to how complex it gets.

 

[dldavies]

Do the drives start individually? It make a big difference to how complex it gets.

No they all start together.

 

[Knobhead]

Give me an hour and I'll have a drawing for you.

 

[Knobhead]

View attachment 11904
Basically press the start P/B and K1 pulls in. K1 then pulls in K2. K2 then pulls in K3. K3 maintains K1. Any trip will break the loop.

 

[Knobhead]

View attachment 11905
Three individual starters.
As usual didn't read the OP fully.

 

[Darkwood]

If you mean that you want all to stop if overload of any trip then if control voltage is all common you just run you stop circuit in series through each overload first before going to your individual start stop buttons for each contactor.

 

[Darkwood]

View attachment 11905
Three individual starters.
As usual didn't read the OP fully.

I read the O/P's query different, i believe he wants to have individual start stop for all 3 motors but if one faults and trips he want the other two to drop out too, so your overloads in this diagram should be in series up front of control and 2 additional start buttons also you missed off.

 

[Knobhead]

Read #4

 

[Darkwood]

Read #4

Ah! missed that but still think he wants any overload to drop out all contactors, and also having one start might mean he has one stop and thus makes sense to series overloads, if the O/P can confirm this for us?

 

[Knobhead]

If you look how it works, all three contactors have to be closed for it to maintain. I've only been using this system for 40 years on conveyor systems.
A little colour may make it clear
View attachment 11906

 

[Darkwood]

If you look how it works, all three contactors have to be closed for it to maintain. I've only been using this system for 40 years on conveyor systems.

Soz tony think im tired i zoomed in and saw you contactor ref'are alternate, i know you dont need to be taught to suck eggs ive been on here long enough but tonight i think that it for me.... must be overworked lol..

 

[dldavies]

Both systems seem fine. Thank you very much for the information Tony.

 

[Knobhead]

View attachment 11907I’ve only just though of this, you can utilise each individual start button as well.
(I’ve never had to do this so it didn’t come to mind).