Remote Starters

[520Talon]

I am finaly hardwiring my van with DC to AC converters. I am going to use it for lights, chargers, ect. Basically I am trying to make it a better service/ camping vehicle. I would like to put in a remote started that reads voltage and starts the vehicle when it gets to low. I have been out of the electronic thing for a while and need some insite as to what will do a good job, cheap.

[LightningGSX]

Other than Design-Tech(junk), I can't think of any brand RS's that have that feature.As long as the RS has a aux start input, any other brand, could be used with some additional electronics.I could help you, if need be.

[520Talon]

I have seen Bulldog units that have it. My first alarm was a bulldog and I will not own another. Auto Command has one but I am unfamiliar with that brand. Any one have some insite or any other ideas.

Lightning, how hard would it be to make a circut that would prompt the started?

[LightningGSX]

Pretty easy actually.I would use a low pin count 8-bit microcontroller such a the PIC12F675($2-$3), which could give it some "intelligence"/adjustability.With the addition of a few resistors($2), filter caps($3) and a voltage regulator($3) you'd be set to go.I have all these parts in stock and would be willing to help put something together.

[520Talon]

Lightning, i got this responce from a camping forum. Do you think this is a good idea?


What a clever idea!

Designing the system that momentarily "presses the button" when the Voltage level gets "too low" will be interesting. I'd like to know what you come up with.

On the other hand just isolating the starter battery from the coach battery is probably sufficient. This'll insure that you'll be able to start the engine when you need to recharge the coach battery.

Then you wouldn't really need to worry about discharging the coach battery too deeply thru the inverter if you choose an inverter that cuts out at some low voltage; most do this at 10.5 V.

If your plan is to quickly recharge your coach battery using the vehicle's alternator, you'll need a three stage charging system.

Unfortunately most automotive voltage regulators built into alternators these days don't do a good job of charging batteries.

The scheme described below is one way around the voltage regulator problem. Also see www.amplepower.com for other approaches.

A way to charge your batteries quickly using your alternator is to hook the alternator to an inverter's DC input & plug a good charger into the inverter's AC output. The charger will quickly charge your batteries.

For this to work the alternator must NOT be directly connected to the batteries, only indirectly connected through the inverter. Therefore you'll need a transfer switch that switches between alternator and battery input to the inverter DC.

The logic is:

IF (ignition is on) THEN
(Alternator connected to inverter DC)
ELSE
(Batteries connected to inverter DC)
ENDIF

A SPDT 12v relay can handle this task.

This scheme seems wasteful of energy because of the 10-20% electrical losses in the inverter/charger system. However, this waste is mitigated by the fact that the engine won't have to run long to recharge thereby decreasing the cost of the engine's inefficiency.

A reasonable charger can also be used for DC power when plugged into an external power source.

This scheme can be set up for less than $200 (not counting extra batteries).