Battery isolator

[diver57]

Just wondering if everyone uses a battery isolator for dual batteries if so what’s a good make to install

[AnEv942]

I am also unclear what OP is wanting to do. So assumed isolating camper from truck (when not running) so as not to drain truck, but that's not what I read?

You wouldn't want to isolate the 2 truck starting batteries from each other. Because of older thread where OPs truck batteries died over winter storage, thinking that might be whats being asked?

Dual batteries in camper, while holding one in reserve seems a good idea, longer run times, battery life and performance is better using both.

Separating- I also use constant duty solenoid on auxiliary charge line isolating camper from truck. Simple inexpensive solution in line on trucks that don't disconnect charge line. Mines a little over 9 1/2 years old.

Bottom line, dual batteries of a bank should be cycled as one, that's how they are wired- to see same load and charge.

[Kayteg1]

I had the combiner on my motorhome conversion and bought it over 10 years ago.
Its solenoid failed after 1 season, when electronic board was still good.
Having bunch of automotive relays, I was planning to parallel 5 of them to do the job, but then in motorhome all batteries were in 1 compartment, so simple disconnect switch was doing the job just fine.
In motorhome I was using alternator to power AC, so you could see continuous 50 amp +

[d3500ram]

Grit dog wrote:
Depends what you're isolating.
....~snip~...I've had good service out of the blue seas ACR I put in the boat.
Never touch it. It opens when it senses charging voltage and closes when it gets below 12 or something safe to unhook the other battery before it is discharged.
No fuss, don't need to do anything it latches and opens as needed.

Isn't there another well known brand using this same technology but more oriented towards RV situations?

I considered whatever brand that was, but opted for the continuous-duty solenoid. Granted those were a little more expensive and the hassle-free operation is convenient, but did I read of more than few that have a tendency for long term failure? The tried-and-true CD solenoids seemed more reliable which made up my mind.

What's the consensus on better reliability of these types of power-sensing idolators?

[deltabravo]

Kayteg1 wrote:
The insulators have several disadvantages.

The OP is talking about isolators, not insulators.

[deltabravo]

Joe417 wrote:
I've been using a 100 Amp continuous duty solenoid for about 5 years. Works great still about $20 on ebay.

Ditto, but I've had mine for about 8 years.

Here's my video

[Camper_Jeff___K]

I've been using a constant duty solenoid,30 amp fuse, and 4 gauge wire. I also have all AGM batteries in the truck camper and truck starting battery for better electrical matching. Truck alternator is my generator when there is no sun for the solar panels.

[Grit_dog]

Depends what you're isolating.
If adding a battery to the trucks single battery, you can but don't need to isolate.
If you're using the 2nd truck battery as a house battery with a dedicated charging circuit or link to the camper battery(s) then I'd definately want to isolate it from the start battery.

If you're talking about adding a 2nd house battery to the camper (similar to in the truck), no need to isolate them from each other. Dedicated chargin circuit from the truck I'd isolate.
Regardless, I've had good service out of the blue seas ACR I put in the boat.
Never touch it. It opens when it senses charging voltage and closes when it gets below 12 or something safe to unhook the other battery before it is discharged.
No fuss, don't need to do anything it latches and opens as needed.

[Kayteg1]

I have 500 amp Jump Pack and it will start my Honda 3000 generator, but you need more for diesel.
Those jump pack delivers boost for few seconds and then you need to reset them.
When you need to wait for Glow Plugs to warm, the jump goes into idle by the time you are ready to crank.
Good item to have as I used it as cellphone charger as well when I was on the beach, but I've got my as a gift for participating on other forum (!) and don't think I would spend the money on it.

[Optimistic_Para]

Kayteg1 wrote:
My other idea is to use truck dual batteries instead of adding more batteries to TC. I hesitated to do it so far scared with possibility of running truck batteries too low for engine start,

Apparently those Lithium Jump Starter packs actually do work, which frankly surprises me because they are so small, so I'm thinking one of them could solve that problem. Example:

Noco Genius Jump Pack

[Kayteg1]

Ford has charging solenoid mounted from the factory, but the program how to activate it is tricky.
Still remember one winter night, when we had low battery warning at 4 AM.
I have remote start on Ford, so started the engine to charge camper battery, but turns out remote start is not activating the charging solenoid.
Had to go to truck and put the key in.
Why other brands don't have solenoids factory mounted?
My other idea is to use truck dual batteries instead of adding more batteries to TC.
I hesitated to do it so far scarred with possibility of running truck batteries too low for engine start, but this season I bought the 1000W inverter generator who with its 20lb of weight is easy to carry as backup even when I don't carry big generator for AC.

[DWeikert]

Joe417 wrote:
I've been using a 100 Amp continuous duty solenoid for about 5 years. Works great still about $20 on ebay.

X2
$14 on Amazon

[Joe417]

I've been using a 100 Amp continuous duty solenoid for about 5 years. Works great still about $20 on ebay.

[Kayteg1]

The insulators have several disadvantages.
-they cut about 0.5v on the other side
-they have low efficiency
-they are prone to leaking the current to ground.
Get yourself modern combiner, what is electronic circuit with HD relay, that works both ways, meaning keeping your vehicle battery topped of when you plug your RV into shore plug.

[d3500ram]

I used a Tekonsha 7000-S battery switch and a 30A reset to isolate the dual truck batteries from the camper. A similar set-up perhaps can be done for a strictly dual battery situation.
Some more info in the install HERE.