Pump control from 2 sources

[Barlidge]

I want to control a central pump from 2 different controllers, I've thought of 2 scenarios and was just wondering if there is any other method I have not thought of. The two solar pump stations need to operate independently of each other but if either one or both of them is on then the pool pump needs to be running.

 

[AdrianH]

A) if using mains power for everything stick a relay in there so that if control point A is operating it it isolates B and visa vera, especially if using mains power so that the possibility of two different main phases from different areas could meet at the pump. ( across a site could be different phases?)

B) Another possibly better way if you can is have the controllers output a DC voltage of say 12 or 24 volts at 1 amp max take each one though a blocking diode to power a relay that then switches on the mains to the pump.

C) If the controller have normally open relay outputs then the commons can be paralleled and the NO output paralleled and used to switch on a relay to power the pump.

Sorry crap at drawing.

Adrian

 

[Barlidge]

Hi Adrian, thanks for the comments, I've added some additional info to each one.

A) if using mains power for everything stick a relay in there so that if control point A is operating it it isolates B and visa vera, especially if using mains power so that the possibility of two different main phases from different areas could meet at the pump. ( across a site could be different phases?)

I have got relays in both options above, are you suggesting I should add more relays? ts at home so definitely single phase.

B) Another possibly better way if you can is have the controllers output a DC voltage of say 12 or 24 volts at 1 amp max take each one though a blocking diode to power a relay that then switches on the mains to the pump.

The output terminals are 240v but that is controlled by a 12v onboard relay, I guess it wouldnt be impossible to de solder the relay and take the 12v signal direct from the board.

C) If the controller have normally open relay outputs then the commons can be paralleled and the NO output paralleled and used to switch on a relay to power the pump.

Dont think that will work as they each need to operate their respective solar pump station independently as well as operating the main pump if either/both or operating.

Sorry crap at drawing.

Adrian

 

[AdrianH]

If all off a single mains supply, same phase then use your first drawing.

Adrian

 

[daleyd]

It's easy enough to do with hard wiring, there are several ways you could achieve the same result depending on how you wire the relays as Adrian says above, or you could do something with an arduino or even even a plc or similar depending how complex you want to make it/how interested you are in messing around with "stuff."

If you just want it to do the job then hardwiring would be the way to go, if you want to have a play around an arduino would allow you to do some neat stuff (auto switchover, duty standby, status indication of which is running/stopped etc - none of which is necessary, but could be quite interesting !)

 

[Barlidge]

If all off a single mains supply, same phase then use your first drawing.

Adrian

Thanks Adrian.

It's easy enough to do with hard wiring, there are several ways you could achieve the same result depending on how you wire the relays as Adrian says above, or you could do something with an arduino or even even a plc or similar depending how complex you want to make it/how interested you are in messing around with "stuff."

If you just want it to do the job then hardwiring would be the way to go, if you want to have a play around an arduino would allow you to do some neat stuff (auto switchover, duty standby, status indication of which is running/stopped etc - none of which is necessary, but could be quite interesting !)

It would be really cool to incorporate data logging functions into it but at the moment with the season half over I really just want to get it functional, maybe I can add those functions for next year.

 

[daleyd]

Yeah, the good thing is you could do it via hardwiring first because it will work just fine and be quick to do, then if you decide to do something more fancy you can re use the same relays etc and just add a controller on top as and when you have the inclination to have a play!

 

[AdrianH]

What is the end project?

 

[Barlidge]

Solar heating for above ground pool, 80 evacuated tubes south westerly facing and 2 flat panels south facing hence the two independent pumps. Al the frames and panels are mounted, solar plumbing side is all done (just pressure testing now). I just have to hook up the dedicated pump (bought from Pete last year) to run the pool water through the heat exchanger and wire up the controls then the final job will be to slide the tubes into the frames.

 

[Barlidge]

then if you decide to do something more fancy you can re use the same relays etc and just add a controller on top as and when you have the inclination to have a play!

There's a nice space on the right hand side just waiting for a future project

I ran the outputs from the controllers through neon sockets as I wanted to be able to see from a distance if either was active, shame the sockets I picked have neons so dim you have to get up really close to see them. The other benefit is I can isolate individual bit easily for testing.

 

[daleyd]

There's a nice space on the right hand side just waiting for a future project

I ran the outputs from the controllers through neon sockets as I wanted to be able to see from a distance if either was active, shame the sockets I picked have neons so dim you have to get up really close to see them. The other benefit is I can isolate individual bit easily for testing.

View attachment 112259

Tidy job.