Dual Battery Isolation Setup

Fabrik8 said:
I'm not sure if anyone has looked at the datasheet for this, but it does everything needed (if I understand the problem). It's select-able to have an engine start isolation function, so that a "start" signal (from the ignition start or whatever) opens the solenoid and isolates the two batteries, and after that it works like any other automatic charging relay with voltage-based isolation/combining. Pretty cool. You can actually have one input signal to instantly open the solenoid, and another input signal to instantly close the solenoid.
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The winch draw might cook it. I'd look for something with a 400 amp intermittent rating.
 
shawn said:
The winch draw might cook it. I'd look for something with a 400 amp intermittent rating.
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That's a good point. The other switched isolate signal could be used to disconnect during winching, but that doesn't protect against something as simple as forgetting to flip that switch, etc.
 
Fabrik8 said:
That's a good point. The other switched isolate signal could be used to disconnect during winching, but that doesn't protect against something as simple as forgetting to flip that switch, etc.
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Easiest way to prevent that, would be to wire the signal to the same switch that engages the in-cab controls. Flip the switch to run the winch, and it isolates the batteries.
 
snipes243 said:
I got a new odyssey PT-1500 34/74 sitting in the garage you can try. Also I would looking into a higher output 3g alternator like a 130 or 140 amp. Lots of the bronco guys have issues with the ECU dropping out when they do efi conversion when they are running the 60 and 90 amp alternators.

One other thing to look at is the ECU wired directly to the battery? Also check the grounds. ECU's will do funny things when they are not wired properly.

I know this is for Holley ECU's not the Howell but the principles are the same.
www.holley.com

EFI Wiring Tips: Proper Ground And Voltage

When installing a Holley or any EFI system to your vehicle, it's imperative to have a proper ground and voltage for the system. The internals of an ECU contain delicate microprocessors and many other components that rely on clean, sound power and ground. Here are some tips from Holley's EFI...
www.holley.com www.holley.com

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So yes the Howell unit has a similar issue if the ECU doesn't have a good connection, as in poor voltage it won't work. The ECU is feed right off the kill switch, which goes to the battery. However, possible that corrosion over time could lead to a voltage drop at that point. I will have to check that when i get home. The gauge in the cab has to be about 11V for me to see the injectors fire, when it gets down below that the starter keeps working down to about 10V which happens more often than not till I decide to go get the jump box. In thinking about it I probably do have a bad connection somewhere on one of the terminals. I've never checked the voltage at the battery when I'm reading below 11V on the guage. If its more than a 1V off then obviously that's the problem and a simple fix.

In looking over the battery specs I'm not sure why the PO used 2 smaller batteries in place of one as a Group 65 or 34 would fit the tray and offer more capacity. In retro spec I think my problem with the battery draining down is probably more related to two small batteries that are 6 years old at this point.
 
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Bebop said:
Wire the winch direct to battery...
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The batteries are tied together through whatever isolation switch you're using. The batteries aren't very big, so you won't get good winch performance when running on a single battery, and could see current spikes of a few hundred amps running across the switch on hard pulls.
 
Desertfox1023 said:
In looking over the battery specs I'm not sure why the PO used 2 smaller batteries in place of one as a Group 65 or 34 would fit the tray and offer more capacity. In retro spec I think my problem with the battery draining down is probably more related to two small batteries that are 6 years old at this point.
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Agreed. The reserve capacity of those batteries has dropped significantly since new, and wasn't that big to begin with.
 
shawn said:
The batteries are tied together through whatever isolation switch you're using. The batteries aren't very big, so you won't get good winch performance when running on a single battery, and could see current spikes of a few hundred amps running across the switch on hard pulls.
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Get a real battery/alt setup and delete the thread :confused:
 
Bebop said:
Get a real battery/alt setup and delete the thread :confused:
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Amen.
I started to reply when he posted the batteries lat night but Id been drinking and decided id be rude and Im trying to stop...or reduce that
 
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Well finally got around to fixing this. Went with the Group 65 as it's the same size as the truck. Which can come in handy both ways.

Best part is it only cost $70 since I had an exchange up for the old spare battery under warranty
 
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