Poor Man’s Shore Power?

[lactic]

I park in a carport and my solar can’t keep the batteries topped off between trips.

Any reason why you couldn’t set up a “poor man’s shore power” by keeping this 3 stage charger hooked up directly to one of the batteries when not in use?

Thanks!

 

[longhorn1]

Why don't you turn off the power until a day before you leave?

 

[lactic]

I have a SnoMaster fridge that I like to keep stocked and ready to roll. Also, in the summer, I like to run the fan to keep the air moving and things cool.

 

[PaulT]

That’s a good smart charger. I have one and would trust it hooked up indefinitely to maintain the battery on float. However, unlike the Iota with IQ4 or a Zamp solar charge controller, it does not periodically revert to bulk,absorption, then float to insure all remains well and I’m not sure that it reverts to bulk mode if the battery drops due to a load.

If you have an Iota/IQ4, just leave the camper plugged into the same outlet where the Noco G7200 would be plugged. If you are running the fridge at up to 5 amps and the fan at up to 3 amps, you will exceed the ability of that 7 amp charger to keep up. The G15000 might be a better choice. Also, if your fridge is a 3 way, that charger couldn’t keep up with its power usage alone.

With the camper plugged into shore power, both 2 & 3 way fridges will run off of AC power automatically.

Do the math with your particular situation and appliance power needs before spending money.

Paul

 

[klahanie]

IDK but if you have a voltmeter I'd say it's worth a try to see how the charger reacts. My concern would be that with a constant load from the fan running the charger will go into absorb or bulk mode, rather than float, exposing the batts to a voltage higher than they may want, since they will be "full". The fridge cycling could be another trigger.

I'll guess, since you are currently using a smart charger to keep the batteries topped up as much as possible, that you are already somewhere on the slave/master spectrum vis a vis us owners versus our batteries. Therefore might not want to risk it. Easy to check with a voltmeter tho.

I think what would work is a separate 12V power supply/adapter/convertor/transformer. Say a 10A, 110VAC to ~12VDC. They can be inexpensive to buy. The fridge and fan prob won't care if it's 14 or 14.5V either. Then wire in a plug type disconnect between the batts and the camper panel. And put a matching plug onto the cord end of the power supply output. You mentioned hooked up to "one battery" (as opposed to both ?) so I'll thinking you might be comfortable with a bit of wiring...

 

[Vic Harder]

I use that same charger. Like Paul says above, it might not be quite powerful enough, but it is worth a try.

 

[smlobx]

That’s a good smart charger. I have one and would trust it hooked up indefinitely to maintain the battery on float. However, unlike the Iota with IQ4 or a Zamp solar charge controller, it does not periodically revert to bulk,absorption, then float to insure all remains well and I’m not sure that it reverts to bulk mode if the battery drops due to a load.
If you have an Iota/IQ4, just leave the camper plugged into the same outlet where the Noco G7200 would be plugged. If you are running the fridge at up to 5 amps and the fan at up to 3 amps, you will exceed the ability of that 7 amp charger to keep up. The G15000 might be a better choice. Also, if your fridge is a 3 way, that charger couldn’t keep up with its power usage alone.
With the camper plugged into shore power, both 2 & 3 way fridges will run off of AC power automatically.
Do the math with your particular situation and appliance power needs before spending money.
Paul

Paul-
I have one of these as well and it's my understanding that it does periodically exercise the batteries to maintain the ultimate state of charge...it is good for up to a 230 AH battery.

https://images-na.ssl-images-amazon.com/images/I/91jdklbeN3L.pdf

 

[PaulT]

Paul-
I have one of these as well and it's my understanding that it does periodically exercise the batteries to maintain the ultimate state of charge...it is good for up to a 230 AH battery.

https://images-na.ssl-images-amazon.com/images/I/91jdklbeN3L.pdf

My G7200 is a previous version that does not have all the features of the newer one. I do have the G15000 also which has the features like Lithium and maintenance mode.

Their online documentation is a little light on technical detail as compared to Iota and Zamp which restart once with bulk mode after some days or weeks at float or after power has been drawn down. Noco's maintenance mode description talks more about the LED indicator than to where it reverts in the charging profile.

I also have their G3500 so that I can charge 6v batteries. Like I said I like their products.

Paul

 

[klahanie]

Since my camper is plugged in I thought to try.

External, clamp on Iota DLS-45 with IQ4 smart charger controller.
No appliances on: 13.47V
Interior lights and furnace blower on: 13.0V
Return to no appliances on: 13.47V

So instead of switching up, as I thought it might, the charger voltage output dropped. EDIT as if their were no sensing or charger, and was drawing from the batts only.

Results were the same with out IQ4 controller plugged in - surprising because I thought this charger would work as a constant voltage power supply without the IQ4. As always YMMV.

lactic, if you can live with the resulting charger voltage for your situation but the charger can't live with the load, perhaps a portable 110V house fan could substitute for the camper fan, taking that load off the camper system.

 

[Hoopy]

I use the shore power hook up and if it’s garaged that iota is a great smart charger that was a FWC suggestion when I bought the camper

 

[RC Pilot Jim]

Lactic,
We too park under a carport, My neighbors south facing white roof keeps the battery at 99% full (Trimetric) with just the light bouncing off the roof between trips (No Load).

We use a "battery tender" type device as our "shore power" the night before a trip to run the Engel fridge and maintain the battery at 100%.

Features

We placed a short 10 foot extension cord between in the area between the camper and the truck bed. The male end threads through a wire tie loop which hangs from a bolt of front of the camper. The other end ports 3 ports. One for the charger maintainer with two spares. In the winter we plug in our space heater with one spare remaining,

Cable cord with dust cap

Adaptor cable plugged into xtension cord

3 ports temporarily threaded through access hatcj

 

[craig333]

I'd think it could keep up with the load. Not like the fridge runs constantly.

 

[rubberlegs]

I'm a bit dense probably, but why not just plug in the shore power cable? Will that overcharge the battery?

 

[larryqp]

Hey RC Pilot Jim,
I did a similar thing, until a mouse came in thru the space created by the cord and sampled all my bread plus shocked the crap out of us when it ran across the floor one evening.
So then I removed the access door, installed a round junction box with a duplex outlet and a metal outlet cover. Haven't had any mice since. I just cut off the female end of the extension cord and attached the wires to the outlet. The extension cord is a fairly short 20amp exterior cord. I carry a second extension cord with me to make the connection to shore power in a campground, when power is available such a many state parks.

Then I plug a 3 to 1 outlet adapter into the outlet and I now have 4 outlets to use if needed or the standard 2 if I don't use the adapter. I only have a Eagle shell, so any electric items I use, which are few, get plugged in here.

 

[craig333]

Maybe its a shell model that didn't come with an IOTA. My guess.

 

[lactic]

Thanks for the replies everyone! Mine is a Fleet shell with just the solar and batteries- no shore power connection.

I let the batteries sit with the charger and it seemed to have “repaired” them by topping them off completely overnight with minimal draw from the chest fridge. Now it seems that my roof mounted 160w panel can keep up and I am hopeful the 100w portable will be able to handle the job when parked in the carport. I’ll save the battery charger for the winter months or prolonged periods of work/no fun if it all works out.