Wiring a pump

[hvw]

I have a pump start relay that is wired for 230v going in and coming out. It is supposed to start a pump that is wired for 120v. The 240v wire from the start relay runs underground to a junction box. I wired the junction box as I would for 230v, that is, black to one leg and white to the other leg. It is grounded. I then put a single breaker in the box and ran that leg directly to the pump. My thinking was that by doing that I would get 230v into the junction box and 120v out to the pump. Is that right? it doesn't work. Ideally the pump should stay wired to run on 120v ( In case there was any doubt, I am not an electrician but I do need some help).

[Louie1961]

Submersible well pump? I have never heard of one running 120 volts from a 240 volt control box. 3 wire pumps (actually 3 wires and a 4th ground) are all 240 volts in my experience. I *think* 120 volt pumps are all 2 wire and don't need a control box. Someone with more experience will come along I am sure.

[hvw]

It's an above ground pump for a sprinkling system. The pump can be wired to run either way. I'm running it 120v because I'm using the remaining power for something else. It worked for several years the way it's wired but the 200 amp main breaker in my house recently failed badly and caused several problems. This is just one of them.

[IAMsteelworker]

Deleted

[danielplace]

Can you draw what you have wired and post it.

So you have a pump start relay you say is wired for 240 volt. Then you say you put a breaker and wired 120 volt directly to the pump.

If breaker is straight to pump and pump is wired with windings in parallel with hot at one end and neutral at the other then it should run.


You have a hot and neutral and a meter reading 120 volt on your pump input ?


How is the 240 volt pump start relay part of the 120 volt going to the pump ?

[scsmith42]

You need to run a separate neutral wire from your load center to the junction box where you're splitting the 240.

Using the ground as a neutral is not a good idea.

[danielplace]

You need to run a separate neutral wire from your load center to the junction box where you're splitting the 240.

Using the ground as a neutral is not a good idea.

Sure hope he wasn't doing that. Oh no !!! I missed him saying that. If he is tapping off 1/2 of 240 what was the 120 volt breaker to the pump all about was guessing the neutral was with that 120 volt to panel. We are just guessing at this unless he post schematic of what he has.

[Willie B]

Pump relay is a bit vague.
I'll guess a relay where the magnetic coil is 240 volt, so he needs a 240 volt circuit to energize the coil.
I'm not clear

Never mind. I'm not clear.

[jpump5]

A drawing of wiring and pic of relay and
wiring would help a lot.

[hvw]

What I have is a pump start relay that runs off 240v power that is connected to the input side of the relay. The output side of the relay goes to a junction box by the pump. The relay is connected to the sprinkler system timer by two 24v wire's which are on the relay. It is connected to the timer by those two 24vires. One is connected to the master valve and the other to the common, both of which are on the timer. When the timer turns a watering zone on it sends a 24v signal to the pump relay. The relay then energizes and sends 240v to the pump which remains on until the timer stops the signal. Then the relay cuts off the output side and the pump turns off. But, my pump is wired internally to run off 120v.

So, to feed it 120v I installed a junction box and put a single pole breaker on one of the junction box lugs. The pump is connected to that breaker. The junction box sits next to the pump and would otherwise send 240 volts to the pump. The junction box is connected to a 10/3 wire. Black to one lug, white to the other lug and the ground connected separately to it's own lug. The pump is connected to the breaker by the black wire. And that supplies 120v to the pump. The pump's neutral wire is attached separately from any ground wires. So what I have is a pump relay that sends 240 volts to a junction box. But I only connected one side of the box to the pump in order to run 120 volts to it. Hope some of this makes sense.

[jpump5]

“…… Pumps neutral is attached separately from any ground wires…..”

Still not completely clear on what you’re doing, but if you’re
creating a neutral from “any ground wires” you can be creating
a very real potential for electrocution, along with other issues.
If you don’t have a neutral in your incoming line to your junction
box, you need to wire your pump for 240v.

[cwby]

Or change the circuit going through the relay to 120V. 120V in/120V out.

[jpump5]

Or change the circuit going through the relay to 120V. 120V in/120V out.

That would work too.
I was thinking if the incoming line was going to be for pump only, pump might as well be wired 240v.

[scsmith42]

What I have is a pump start relay that runs off 240v power that is connected to the input side of the relay. The output side of the relay goes to a junction box by the pump. The relay is connected to the sprinkler system timer by two 24v wire's which are on the relay. It is connected to the timer by those two 24vires. One is connected to the master valve and the other to the common, both of which are on the timer. When the timer turns a watering zone on it sends a 24v signal to the pump relay. The relay then energizes and sends 240v to the pump which remains on until the timer stops the signal. Then the relay cuts off the output side and the pump turns off. But, my pump is wired internally to run off 120v.

So, to feed it 120v I installed a junction box and put a single pole breaker on one of the junction box lugs. The pump is connected to that breaker. The junction box sits next to the pump and would otherwise send 240 volts to the pump. The junction box is connected to a 10/3 wire. Black to one lug, white to the other lug and the ground connected separately to it's own lug. The pump is connected to the breaker by the black wire. And that supplies 120v to the pump. The pump's neutral wire is attached separately from any ground wires. So what I have is a pump relay that sends 240 volts to a junction box. But I only connected one side of the box to the pump in order to run 120 volts to it. Hope some of this makes sense.

As long as you have a dedicated neutral running from your load center to the pump, what you describe above will work just fine. It is ok to start a 120V pump from one leg of a 240V relay (contactor) as long as there is a separate neutral to the motor. Basically you're only using one leg of the 240 relay.

If the relay (contactor) ever needs replacement, I'd suggest you replace it with a 120V equivalent.

[danielplace]

The relay is just a switch. It is a double pole single throw switch. The coil is 24 volt. The contacts do not know or care what the voltage is on them or it there is one or both sets being used.

Why don't you do it properly and come out of breaker and feed one side of relay. Leave that side and go to the pump. Wire your neutral straight through panel to pump.

I do not understand all the confusion with a single pole switch. Use side like a single pole switch to your 120 volt hot leg.

24 volt to coil. 120 breaker to line side of relay. Pump wire to load side and neutral panel to pump.

[danielplace]

OP posted on another thread.

Thanks to all for the advice and suggestions. I believe I'm either going to wire the pump for 240v or just continue running a 120v leg to the pump. The thing was working for years until we had the electrical storm which burnt up the main breaker. It created all kinds of problems that I'm just now getting resolved. The pump business was just one of them.