Breaker 12v and 220v

[uniopp]

Is there such a thing as a double breaker that has a separate DC and AC line passing through it?
I need a 12v (25 amp) line and a 220v (15 amp) line that if one is tripped the flow on both lines will stop.
I’m using it for a 220v (15 amp) marine air conditioner that requires a 12v (25 amp) water cooling pump running at all times the air conditioner is running. I want one breaker switch that turns them both on/off together and will trip if something goes wrong on either line.
The purpose of both being on the same breaker is so one can’t run without the other - one switch controls power to both.
I would appreciate the correct name/model number of what I have described above (or a more suitable suggestion if better).
Thanks

[Greg Brannon]

Doesn't the air conditioner have an output to control the pump? Of is this a Franken-AC setup?

Greg.

[uniopp]

Originally Posted by Greg Brannon

Doesn't the air conditioner have an output to control the pump? Of is this a Franken-AC setup?

Greg.

It’s a Marbru marine air conditioner that I think would need the external relay controller for a pump.

I have since found out that I could use a water flow switch to only allow power to the air conditioner when the pump is on and water is flowing. I think that might be the best solution.

What do you think?

Thanks

[SailingHarmonie]

Originally Posted by uniopp

It’s a Marbru marine air conditioner that I think would need the external relay controller for a pump.

I have since found out that I could use a water flow switch to only allow power to the air conditioner when the pump is on and water is flowing. I think that might be the best solution.

What do you think?

Thanks

So…. Why not add the external relay controller? That is by far the best solution.

All the other jury rigs you are thinking of will have the pump running all the time instead of cycling with the compressor as it should. There are several reasons you do not want that.

[uniopp]

Originally Posted by SailingHarmonie

So…. Why not add the external relay controller? That is by far the best solution.

All the other jury rigs you are thinking of will have the pump running all the time instead of cycling with the compressor as it should. There are several reasons you do not want that.

As far as I know the Marbru pump control box is for a 115/230 water pump but my water pump is 12v. Should I use that control box with a 230v AC converter to 12v DC? This setup would be far more expensive than other solutions.

In regard to my flow switch solution, my 12v pump would only be turned on for the purpose of using the air conditioner and turned off when not using the air conditioner. I would have one 12v breaker that would act as a mains switch for the pump and restrict the air conditioner starting without water flowing through the air conditioner. I would have thought this solution provides better protection for the air conditioner because if the pump breaks down or is blocked the air conditioner will stop.

Thanks

[tanglewood]

Use the 120/240V pump control from the HVAC unit to operate a relay that switches the 12V pump on/off. With most HVAC units, the compressor cycles on and off, and that output turns the pump on/off with the compressor. You want to accomplish the same thing, and the relay will do that. There is no need to run the pump continuously when the HVAC is on, only when the compressor is actually cycled on.

[HeywoodJ]

Not getting into whether there are other solutions, the the answer to the OP's direct question depends on the physical relationship between the two breakers.

It would be unusual for them to be adjacent to each other since they are on different buses, but if they are adjacent then a "handle-tie" will cause the tripping of one breaker to open the other. And also allows you to turn both on/off together. Handle ties fit on breakers of the same make/size/configuration, but you can probably find Carling breakers in both 220AC and 12DC with the same form factor that would accept a handle tie. If your breakers are the standard white toggle handle you may see a hole in the rounded end, that hole is there to accept a handle tie, which is basically just a pin that goes through the holes in the handles of the two breakers. They do need to be made/rated for the tie so that there is enough opening force from one breaker to open the other.

Carling does offer "Dissimilar Multi-Pole Breakers" that would fill the bill, but these are custom built, a one-off would be somewhere between expensive and not available.

Option B is a shunt trip, this is much more complicated and allows an auxiliary contact on one breaker to trip the other. The relay/flow switch solutions would be far easier than a bi-directional shunt trip.

[uniopp]

Originally Posted by tanglewood

Use the 120/240V pump control from the HVAC unit to operate a relay that switches the 12V pump on/off. With most HVAC units, the compressor cycles on and off, and that output turns the pump on/off with the compressor. You want to accomplish the same thing, and the relay will do that. There is no need to run the pump continuously when the HVAC is on, only when the compressor is actually cycled on.

It looks like the control box has a relay inside but I don’t know how to connect to it. Would one of the outgoing connections be used to power the pump?





Thanks

[Greg Brannon]

Why not call Marbru and ask them for help? Their site appears to be active with phone and email available for owner support.

Greg.

[uniopp]

Originally Posted by Greg Brannon

Why not call Marbru and ask them for help? Their site appears to be active with phone and email available for owner support.

Greg.

I’ve asked them the same question but still waiting for a reply.
Thanks

[Greg Brannon]

They may be reluctant to answer (or perplexed) because the setup you're suggesting is non-standard and possibly unsupported. I'm pretty sure it is unusual for an A/C air conditioning system to have a 12-volt coolant pump, but I could be wrong. Pump control signals from the AC's control board would typically be at the voltage required to run the pump.

Maybe you've asked them the wrong question. Explain that you've acquired this installed system without documentation, and you need support to maintain/repair it. You should have an install manual which should answer the questions you've been asking about what the relays and control board do plus the pump specs recommended or required for the AC unit.

Greg.

[Mickeyrouse]

This may over-simplyfy the situation, but I’ve seen this: two Carling (sold as Blue Sea Systems) breakers are mounted side by side. The circuit breakers should be rated for the load on the respective circuits. The breaker toggles have holes transverse. A #10 machine screw prox. 1-1/4” is inserted through the holes in the toggles then nutted. When an over-load causes one breaker to trip, the other is sure to follow.

[tanglewood]

Originally Posted by Mickeyrouse

This may over-simplyfy the situation, but I’ve seen this: two Carling (sold as Blue Sea Systems) breakers are mounted side by side. The circuit breakers should be rated for the load on the respective circuits. The breaker toggles have holes transverse. A #10 machine screw prox. 1-1/4” is inserted through the holes in the toggles then nutted. When an over-load causes one breaker to trip, the other is sure to follow.

Just confirm that the specific breaker is designed to cross-trip via the toggle levers. Not all are. In fact, when I looked into this it appears that most are NOT designed to cross trip that way and that the interlocked toggles is just to enable simultaneous manual on/off operation. On some the cross tripping is done by a proprietary link between the breaker bodies.


THE AC unit in question is just like most others where the compressor control is meant to also control the pump. t appears to be the P1 and P2 terminals on this model. The only issue is that the pump is 12V, and a simple relay will solve that problem. Yes, two separate breakers will be required, but that's life if you want to use two different voltages to control the AC.

[capt jgw]

I believe AYBC does not allow DC and AC in the same panel. They can be on separate panels adjacent to each other but not intermixed.

[Matt Johnson]

Edit: just looked at their site and I see they have standard compressors for most models and not variable speed as I thought. (Only the 17 is showing variable).