# Wiring Diagram



## septiclecky (Oct 17, 2008)

skyline2500cc said:


> I am looking for an electrical circuit for the control of three pumps. Can anyone suggest a place that I could find such a circuit.
> I realise that it would be easier to do with a PLC but I would like to be able to hard wire using relay logic and timers only.
> the control would be 24dc or 110 ac the pumps are 415v ac with the
> Logic would be duty assist assist controlled by three pressure switches.
> ...


You need to give more info on how you want them to run eg 1st as a duty pump, 2nd as back up pump and 3rd as a spare, what are they pumping? how is each to be started etc


----------



## skyline2500cc (Oct 21, 2008)

The pumps will have a duty selector switch or an auto changover facility. The auto change would be initiated on time or every time the pumps stop after reaching a pressure switch setpoint. A Hand Off Auto facilitywill be available on all three pumps and protection via an e/stop and motor overload. 
operation will be duty, assist assist.
pressure switch 1 falls below setpoint and first duty pump starts.If the high setpoint is reached within a set time the pump stops. If not the assist pump starts and it must achieve setpoint on pressure switch No.2 within a set time. If pressure is achieved the both pumps stop if not the second assist starts and when the pressure switch No.3 setpoint is achieved all three pumps stop.
If any duty pump fails the next available becomes duty.
The fluid being pumped is water 
Hope this is not to long winded
skyline2500cc


----------



## Nodoggie (Oct 17, 2008)

I'm not going to draw this, but i think basic schematic would be:

1.) 3 emergency mushroom stops in series. 
1A.) In series with Pressure Switch (N.O.)
1B.) Motor 1 in parallel with holding contact
1C.) In series with ice cube timer relay (N.O.)
2.) Motor 2 in parallel with holding contact
2A.) In series with ice cube timer relay (N.O.)
3.) Motor 3 in parallel with holding contact

note: don't forget O.L. heaters


----------



## electures (Oct 23, 2008)

Do you need an alternator to distribute wear evenly? It will be cheaper to use a PLC. A MicroLogix w/analog would work perfect. Ebay has them cheap sometimes. Good luck!


----------



## skyline2500cc (Oct 21, 2008)

Many thanks for your help 
cheers
Skyline2500cc


----------



## Nodoggie (Oct 17, 2008)

no prob.


----------

