12v wheelhouse question

[Glockwinger]

OK, thinking out loud here...

So I have been kicking this idea around in my head to upgrade the 12v electrical "service" in my wheelhouse. Right now I have two separate batteries...one for the forced air furnace, and the other for the radio and lights. Each battery has an on board charger for when I run the generator to recharge the batteries. I have been toying with the idea of a 12v converter with a distribution fuse box for around $150 to charge the batteries and take up the 12v load when on generator power.

However, if I purchase 12Amp 12v power supply for about $60, I could just disconnect the quick connects from the batteries and hook them to the power supply for when the generator is running, and the batteries would get charged without any load or drain on them during charging and the power supply would run heater, radio, and lights.

It might be a pain to connect and disconnect the batteries when not on generator power, so I may have to find some kind of switch I could use to switch between the batteries and the power supply.

Any thoughts by you 12v gurus? Anyone else have some kind of setup with a converter or power supply that you can share info or pictures?

Thanks...

[Glockwinger]

No one has any ideas on this? Hmmm...

[huntnfish]

I plan to get a wheel house in the next few years and I plan to look into getting a wind turbine for it. Its very rare that there's no wind and it will keep your batteries charged without overcharging them. Here is the thread on them. Wind Generator

[delcecchi]

I don't think a 12 volt power supply is the hot ticket to charge batteries, if that was the question. They do different things.

[Glockwinger]

The power supply would be used to power the heater blower while the batteries are charging.

[delcecchi]

The power supply would be used to power the heater blower while the batteries are charging.

OK, I misunderstood what you were considering.

[Tom7227]

Why would you have to disconnect the batteries while they were on the charger? The generator should have enough ooomph to charge them up while they are still connected. In fact I don't see why the fan couldn't still be on while charging.

[Glockwinger]

Tom,

Currently that is how I run my setup. Last year I was out for a week and it was COLD so the heater ran a lot. When I ran the generator to charge the batteries, I think the charge and discharge rate was about equal due to the amount of juice I was drawing. It just got me thinking. For one or two days, I am usually fine. I may have to get a different battery than the marine deep cycle I currently use. Maybe an optima or similar. Thanks to all for the input.

[delcecchi]

Unless the new battery has more capacity it won't help. A bigger charger would help since then it would overcome the drain.

[MuleShack]

check out how some of the big names do it.

Mine (lodge) has a box with circuit breakers in it and a fan to cool it.

When generator is plugged in, furnace is running off of 12V but coverted 12v from the panel because I dont even need to have a battery connected for it to run. if i do have a battery connected it just gets charged. it also must direct power between the 110 and 12v, so not sure what its called or who makes it but that's what it does.

[Lip_Ripper Guy]

This seems to be the best option. I am installing the Progressive Dynamics PD4045 in mine. It has 5 different AC circuit breakers, and about 20'ish DC circuits. It really simplifies the wiring and charging systems.

[rustysetter]

X2 with mule shack with the eception that I have 2 optima's.

[Whoaru99]

It can be done relatively easily with a DPDT relay (or manually with a DPDT switch). When the 120V is connected the relay switches wheelhouse power from the batteries to the power supply.

Perhaps could use just SPDT switching and leave grounds common, but with DPDT the power sources are isolated, for what it's worth.

Also, the small Bosch-type SPDT relays often used in cars and such are common and relatively inexpensive, and typcially rated at 30A. A pair of those, one for positive and one for negative switching, could be used instead of one DPDT relay.

The only fly in the ointment I can think of is maybe there could be a lag in transfer time from power supply back to battery, depending on the load you have going in the house. If there is no or little load then it could take some seconds to drain the capacitors in the power supply down to a level that allows the relay to switch back to battery. Easily solved by leaving on a load. Worst case you could use 120V relays and go on that side and it would be pretty much immediate transfer, but I'd rather stick with low voltage control.

[Glockwinger]

Whoaru99, thanks for the diagram. Gives me some more to think about.

[delcecchi]

Couldn't you make the 12 volt - (negative, neutral, ground) common and save one pole on the relay? In fact you could replace the relay with a toggle switch? (assuming you find the proper rating switch)

[Whoaru99]

Yeah, I mentioned that you probably could, but I prefer isolation.

And, yes, you could use a toggle switch too but the relays for automatic switching are minimal cost, <$10 if you shop right. A good, HD toggle switch is not far from that same cost. Why not have automatic transfer for about the same cost?

You could also put a manual override switch on the relay by using just a SPST switch on the control power.

[delcecchi]

Yeah, I mentioned that you probably could, but I prefer isolation.

And, yes, you could use a toggle switch too but the relays for automatic switching are minimal cost, <$10 if you shop right. A good, HD toggle switch is not far from that same cost. Why not have automatic transfer for about the same cost?

You could also put a manual override switch on the relay by using just a SPST switch on the control power.

So you did. I looked at the diagram and sort of skimmed the narrative. Missed it. Sorry.