250 amp (or higher) Battery Isolator Kit? (1 Viewer)

[r2m]

Hey all,

I have a 230 amp aftermarket alternator on my 1998 LC and dual batteries. I've been looking for a high amperage battery isolator kit. The highest amperage kit I've seen has been only 150 amp. I'll fry something using that. I've seen much higher amperage isolators but not as a kit. I'm a mechanical engineer not an electrical engineer. I manage with electrical to do installs with directions, but that's about it.
Anybody have a kit or company they can recommend?

I am not looking for a "switch" where one manually switches between batteries. I'm looking an active switching isolator to keep my "house" battery (for accessories) charged while driving and to keep my "start" battery isolated while using accessories.

Or has anyone created their own kit purchasing a high amp isolator, wire, etc. and doing their own install?
If so, can you please provide a bill of materials and diagrams, photos or description of your install?

I need to finish this dual battery project I stated a couple years ago.
Yea, I've been kind of busy...

 

[r2m]

Can't believe no one has ever installed a 230 amp plus isolator kit on their rig!!
Anybody have any input??

 

[gatormark91]

500 amp. Use it to isolate my winch battery.

ML-ACRs - Blue Sea Systems

 

[r2m]

500 amp. Use it to isolate my winch battery.

ML-ACRs - Blue Sea Systems

How did you wire that? More specifically, where/what did you connect that to your "house" wire? Did you add another fuse box? Do you have any pictures?
Also, I'm going to be getting some armor soon (read: steel bumpers, sliders and skid plates) which will have a winch also, so I'm very interested in wire configurations.

 

[gatormark91]

I don't use a house wire, but will probably put an additional fuse block on the factory battery for the couple small things I run. Not running a fridge or any big audio stuff, so don't need it, really. I'm re-doing some of the cabling this week, but I can take some pictures of what I have when it's the way I want it. I have it wired like this:

winch battery >2AWG wire> 300A ANL fuse (on bracket I made to go between fender and air box) > splitting to two 2AWG two wires, one going to on/off for winch, the other going to the ML-ACR (mounted to radiator support in front of air box). Then from ML-ACR, 1/0 AWG across the top of the radiator ( upped to 1/0 since longer runs have more resistance) to another 300A ANL fuse in a holder mounted on top of the factory fuse block, then to the factory battery location.

This way, I can turn off power from the factory battery to the second battery, isolating the winch to the passenger side ANL fuse and second battery. Then I switch on the winch switch, and winch away. I have a spare 400A ANL fuse for a backup in case the 300A can't handle the load needed from the winch. Don't think I'll ever need to do that kind of pull, but the fuse is there if I need it.

 

[100 TD]

The highest amperage kit I've seen has been only 150 amp. I'll fry something using that.

What are you using that draws 150+ amps continuously?

I'm looking an active switching isolator to keep my "house" battery (for accessories) charged while driving and to keep my "start" battery isolated while using accessories.

You can use any VSR (voltage sensitive relay) to switch a larger solenoid if so desired. To clarify your use, how many and what size in A/Hr capacity are your house batteries, and what do you use them for?
One thing to understand, whilst you alternator may be capable of producing 230 amps, most likely the only time it ever would, would be when winching.
A lead acid battery's ability to accept a charge is controlled by the chemical reaction and internal resistance of the battery.
For a ~100 A/Hr battery...........
So lets say you "dead" flatten your house battery to 10.5 volts. You start your car, the main battery charges up to the preset voltage of approx 13.2 volts for 5 or 10 seconds before your battery isolator switches your house battery into circuit. At that point it starts accepting a charge at a high rate, but that rate falls very quickly, and generally, in 10 seconds would probably fall below 100 amps, due to the internal resistance of the battery.
Even having a 500 amp alternator will not fully charge that battery in one hour, because of the chemical make up of the battery, "basically" it may accept 50~100 amps for the first 1/2 hour and 25~50 amps for the next 1/2 hour and 10~25 amps for the next 1/2 hour and 5~10 amps for the next 1/2 hour, and 2~5 amps for the next 1/2 hour and then finally a trickle for the next few hours until fully charged.(dependent on battery).
So your battery isolator will not see 150 amps for any "significant time period" to be concerned about.
Winching - If this isolator has a manual mode which is used when winching.
EDIT: I need to clarify this a bit, as what I wrote without a wiring diagram was a "general" description.
When winching from both batteries, manual mode selected, and your winch drawing it's maximum current, say 450 amps, that's 225 amps from each battery. The alternator is running, you have the engine revving, and the alternator is outputting "up to" 230 amps. So 110 amps minimum from each battery leg ( 110 thru the isolator to the winch). If you only use your house battery for winching, then a max of 230 through the isolator. Remembering, the alternator also still has to supply the engine and all other accessories as well so probably more like 175A maximum through the isolator for a short time.
As soon as you stop winching, the house battery can now receive a charge from the alternator. In the real world I doubt the alt will output 230A and more will be drawn from each battery, until the batteries get down a bit. If you connect your winch to your house battery (DON'T), then your isolator will try to handle the current of your main battery plus the alternator, ~300 amps, and whilst it can probably handle it for a few runs, it will ultimately fail at some point down the track. So hook your winch to which ever battery has the permanent alternator feed to it(normally your main battery)
Your alternator specification will also be at a certain speed, a certain temperature and would rarely ever output that actual specification in general use. If you think you will be doing regular "serious" winching, I would recommend using one of these, and when you get out to hook up the winch, turn this sucker on and go for it, turn off when you put the winch away. HD-Series Heavy Duty Selector Battery Switch - Blue Sea Systems or other high current electrically operated solenoid.

Solenoids, their ratings, you need to find what they are, continuous duty, intermittent duty etc. A standard 100A continuous duty solenoid type isolator may have an intermittent rating of 400A for 10 seconds. (By the way, the solenoids in a standard Warn winch{up to a few years ago at least, I haven't check late model ones} are 100A solenoids)
So the products below, or many other like them, are generally very adequate for the job you describe, unless there are particular specs/usage scenarios you haven't told us about.
https://www.redarc.com.au/Content/I...arc brochure - SBI Smart Battery Isolator.pdf
Electronic Battery Isolator | Intervolt
Single Rectifier Battery Isolators

There are many automatic battery isolators, some are solenoid, some are MOSFET, some are programmable, some have multiple relays in parallel in them to achieve their current ratings. I won't go into all the good and bad about each, however, from my experience doing repairs, "I personally" would stay away from the ones with multiple relays in them as the load can be unevenly shared across the relays due to different contact resistance then they can burn out. I have used a Redarc SbI12 for 15 years, I don't do a lot of winching, if I did, I would fit the Blueseas switch as well. YMMV

 

[Odyseuss]

I believe that the T max(thread here
T-Max Dual Battery Install)
and many dual battery kits for that matter use a 250A(or higher) rated solenoid.

I've been thinking about switching to a blue sea ML relay with its very low power usage.
ML-RBS Remote Battery Switch with Manual Control - 12V DC 500A - Blue Sea Systems
or they have the Automatic Charging relays if you prefer automatic function.

I use a 500 A blue sea switch for a winch disconnect. there are more details on my setup in that build thread too. Pg 2 +7.

 

[gatormark91]

I'm running a manual Blue seas 500A switch as well to turn power to the winch on and off when not in use.

 

[100 TD]

I've just put a note in my post about which battery to hook up your winch to, I have seen a lot hooked up to the second battery on the downstream side of the isolator, this makes the isolator take more current than it need to if it is only a ~100A continuous duty solenoid. I recommend always hooking up to which ever battery gets the alternator feed (normally the main battery), but better still, put a proper high current combiner in if you are going to be winching, either a manual or electrically operated one. One plus for the Blueseas manual switch is the ability to totally isolate the winch, as well as select from either or both batteries. By totally isolating it, you can't get someone coming along and "playing" with you winch, if it has no power.

 

[brizzle]

I love the blue sea as well and have put it on a few rigs at this point. I did a bunch of videos on my install not exactly a how to but might help you out if you go that route. I would be happy to answer any questions you might have.

Land Cruiser Dual Battery Build - Building Bernard Project 2.1 - YouTube

 

[Ager Venator]

My coworker paid for a Blue Sea setup (I think he paid around 400$) from an off road supplier. I'm going to use something similar but do the wiring myself. People seem to really like the Blue Sea.

 

[catz]

Dual Operation VSS (Voltage Sensitive Switch) 275A Cont Motorized 701-MDVS

These Voltage Sensitive Switches (VSS) automatically sense connected battery bank voltages and provide optimal, efficient charging of the second bank. The VSS allows for independent battery banks to be combined or isolated based on the presence of a charging source (such as an engine alternator or battery charger), while also offering remotely activated, high current, emergency parallel connection. Designed and constructed for longevity in the marine environment with tinned copper conductors, stainless steel nuts, and high temperature, fibre reinforced plastics. The units are ignition protected, provide On/Off switching operation, and may be recessed or surface mounted. The remote emergency parallel function can be operated through a momentary button on the dash which will parallel the batteries for 10 minutes. Once this 10 minutes has passed, if the voltage is high enough, the voltage sensitive switch will stay engaged. If not, it will disengage.

• Dual battery sensing
• Manual override option

Dual Operation VSS (Voltage Sensitive Switch) 275A Cont Motorized | BEP

 

[scottm]

EATON's Sure Power 3104 Battery Interconnect Controller | Waytek

Sure Power: Multi-Battery Isolator - 240 Amp ∼ 1 Input; 2 Output