Is there an aftermarket module that will restart your truck when aux. batteries low?

[Coalsmoke]

I am planning a new work truck, and one of the things I want on it are two deep cycle marines and an 1000W inverter to run 500-700 watts of auxiliary lights when needed. I don't want to idle the truck all the time, and I am hoping that there might be some sort of aftermarket electronic control box that will sense when the auxiliary voltage gets down to about 10. 5 volts and will restart the truck until the batteries are charged and then shut the truck off again. I thought maybe there is somethign like this on the commercial trucks. Maybe a little generator would be easier. I just thought I'd put this out there to see if anyone knows, as I don't even know where to start looking. Tried a couple local truck accessory places but they didn't know.



Thanks guys

 

[GWBourne]

couldnt you look into a remote starter? then you could atleast keep on doing what you were doing and start the truck from afar... i think that would help a bit.

 

[PToombs]

The guy at work just bought a new 2000? watt inverter from Harbor Freight. (No flaming please! ) It has an auto shut off when it reaches a certain voltage, like 11 volts or so. I know he hasn't tested that feature yet, but he will! :-laf Might be something to look into.

 

[JoshPeters]

I would also look into a high idle feature. The alternators dont' charge well at an Idle RPM. 1500-2000 would be much better. It would also be better on the engine.

 

[Bernie]

Simple Solution

-Get a compustar remote starter because it has a remote input for low temperature.

-The temp sensor just connects (or disconnects, I can't remember) the two wires of the sensor and that starts the truck.

-Galls sells a module that is designed to disconnect an electrical connection (warning lights on a cop/fire vehicle is their example) should the voltage fall to a certain point. Put that device on you battery, wire it to a relay and use eithor the NO or the NC (depending on if you need to make or break a connection) output on that relay to go to the input on the compustar.

-Get the high idle engaged on you truck. They don't make much juice at idle. See other posts on that subject (I think pin #22 to ground, but don't quote me).

-I've done something similar to this for a security application. PM me with any other questions.

 

[Coalsmoke]

Thanks guys, I appreciate all the ideas. A key feature for me will be for it to start before the automatic 10. 5volt shutdown of the inverter kicks in. Bernie, your idea is the best I have heard so far. I'm thinking it might be easier to just idle the truck when the extra lightpower is needed, because this won't be an everyday thing (yes it will be exhaust brake equipped). I have a light bar that I made that uses 8 halogen lamps, and works quite well, I am just trying to get away from having the truck running that often when not entirely needed. I guess one of the hard parts would be to have something that senses when the batteries are charged again, as the altenator would be feeding the charge voltage and that could fool a simple shutdown circuit into thinking the batteries were charged. Maybe plain old 12V flood and spot lamps will be the easiest way to go, instead of this 110v inverter idea.

 

[JGK]

Last spring I had to have my alternator rebuilt. I mentioned to the guy in the shop that after driving across town to their place with the faulty alternator (using battery power only for all electical requirements) the batteries were getting low and I'd have to drive around a while to recharge the batteries. He said the alternators on the newer vehicles don't recharge the batteries! At least on our Dodges. Once the truck is started, the alternator takes care of most of the power requirements of the truck. So, he said, I'd have to put the batteries on the charger to get them back up to full charge.



If anyone knows otherwise, please chime in.



Coalsmoke, I think if I had your requirements, I'd find a small, maybe used generator, like a little Coleman Powermate 1850 or equivalent, if that'll meet your needs. Multiple uses and easier than figuring out a truck restarting system. In fact, I did, and bought the generator. Found it locally for $350 with about 5 hrs use on it.



-Jay

 

[drury]

JGK, your shop guy is full of it. Next time, ask him what does actually recharge the batteries if the alternator doesn't do it. They lose quite a bit of charge every time you start the vehicle. Are you supposed to put them on a charger after every 20 starts?

 

[drury]

Coalsmoke, you ought to be able to use a timer of some sort to turn the thing off. There is no need to wait until the batteries are fully charged. Just run it for 10 or 15 minutes, and that should charge it up to a safe level. You can experiment to find a time that works well for you.

 

[rperker]

alternators only put out the amount of energy being used. there is a circut that makes the alternator full charge for a period after a start. that is what is supposed to keep up with starter use.

 

[JFaulkner]

The shop is mostly right. An alternator is NOT a battery charger, they will however recharge what little is lost during an average engine start. But they are very poor at recharging a dead battery(s). Ask anyone that has a large car stereo (by large I mean several thousand actual watts) and ask them how many alternators they've been through. I went through 4 on one car in a year (in highschool) and that car had 3 large batteries.

 

[Willys]

-Galls sells a module that is designed to disconnect an electrical connection (warning lights on a cop/fire vehicle is their example) should the voltage fall to a certain point.

That sounds like a Priority Start. IIRC it will disconnect the batteries when voltage drops to 11. 5V. A good thing to have regardless of whether you plan on using lights with the engine off- if you drain the batteries accidentally this will preserve enough juice to get it started again.

 

[Bernie]

Thanks guys, I appreciate all the ideas. A key feature for me will be for it to start before the automatic 10. 5volt shutdown of the inverter kicks in. Bernie, your idea is the best I have heard so far. I'm thinking it might be easier to just idle the truck when the extra lightpower is needed, because this won't be an everyday thing (yes it will be exhaust brake equipped). I have a light bar that I made that uses 8 halogen lamps, and works quite well, I am just trying to get away from having the truck running that often when not entirely needed. I guess one of the hard parts would be to have something that senses when the batteries are charged again, as the altenator would be feeding the charge voltage and that could fool a simple shutdown circuit into thinking the batteries were charged. Maybe plain old 12V flood and spot lamps will be the easiest way to go, instead of this 110v inverter idea.

The Compustar has a timeout feature. Have it run for 15 minutes at high idle. That should more than take care of it.