How can I connect a pump controled via 3 independent switches?

[BMW]

Hi
Need some advise. Got a customer who has a air pump switched via a switch fuse. It's a dentist and the pump feeds air to 3 work benches. Now he wants the pump switched by 3 indipendent switches at each bench rather than the one.

I'm thinking a contactor /relay between the mains and pump a switch fuse on the live side then fusing down and wiring the 3 switches like a domestic instalation (2-2 way and an intermidate switch) this feeds the coil to the contactor / relay. That way each switch will turn the pump on and off. The switches can be normal as they are only switching the coil not the load.

Can anyone who has the relative experience see anything wrong in my suggestion. I am a Qualified sparky but this is out of my normal area of work and being on my own have no one to bounce ideas off. Can anyone help.

Cheers

 

[Knobhead]

I'd extend the design so far to include a solenoid valve on each air line to each bench.
Replace the SP switches with DPs, the 2nd pole to energize the solenoids.

Typical tiffy! Over complicate things!

 

[Knobhead]

Tony when do you sleep?what ever time I log your here.lol

Insomnia

View attachment 12096

 

[Silly Sausage]

Typical tiffy! Over complicate things!

No comment...
well, complicated for a HV tech, maybe; no finesse you chaps :tounge_smile:

 

[Knobhead]

Touché.

We do have our delicate side at times.

 

[Silly Sausage]

I know you've been teasing for weeks, my soft spot gave in!
Round 2...

 

[Knobhead]

Come on, the needling between electrical technicians and instrument artificers has gone on for the last forty+ years I’ve been kicking around in the industry.

Electrical technicians were always the higher paid, we could do both jobs!