Low voltage disconnect for ALL loads (1 Viewer)

[Beej]

Hey folks,

I've seen threads for people using the blue sea m-lvd (low voltage disconnect) for accessory loads like fridges. Would this also work for all loads? I'd like something like this that would also work if I leave a dome light on or similar.

Any ideas?

This is what Google produced as a solution: PriorityStart! 12v ProMax Low Voltage Disconnect Switch - PSI-12V-PROMAX

Thanks in advance for any replies.

-- Beej

 

[Beej]

Bump for morning crowd!

 

[danthman114]

Damn this website...

 

[mct75]

Any relay should work just fine. Just don't mess with the starter motor connection.

Everything that is not the starter only pulls like 50 amps I bet so it shouldn't be an issue.

 

[Beej]

Any relay should work just fine. Just don't mess with the starter motor connection.

Everything that is not the starter only pulls like 50 amps I bet so it shouldn't be an issue.

So it seems like one can't install something like this at the battery??

I'd need to go past the fusible link?? Does that sound right?

 

[SmokingRocks]

Damn this website...

Right?! Another thing that I never knew I needed that I can't live without now.

 

[NLXTACY]

It's a great idea and now something else to add. I need to figure out how it all connects with all the crap I have going on in my truck.

 

[maxamillion2345]

Everything is low voltage on the 80s, its the amps you want to pay attention to.

 

[danthman114]

This website is causing me to spend more money... At least I'll have a kickass landcruiser to drive to the poor house...

 

[inkpot]

It's a great idea and now something else to add. I need to figure out how it all connects with all the crap I have going on in my truck.

Can you design one of these that works from Bluetooth on my Smartphone?

 

[NLXTACY]

Can you design one of these that works from Bluetooth on my Smartphone?

You laugh but believe it or not that is EXACTLY what I was designing with one of my ex-employees from my last company. Some of our products communicated with linear actuators, lens control, meta data acquisition. All thru wireless spectrums per country and thru Bluetooth. I was designing a Bluetooth thermostat for our fridges and exactly what you just asked for, a notification system to the phone for not only a battery shut off but also for controlling auxiliary switching using can-bus. This was all before Switch Pros and SPod really started taking off. But, he found a job designing for GoPro and I jumped head first into Wits' End

Heck, I still have the app working on my spare phone that was a proof of concept

 

[surfpig]

Damn this website...

 

[Beej]

Shoot. I know it's a great idea!

But how would it work?! Where would the device be installed to avoid interfering with essential components? Or would one just disconnect the hot lead, install a relay and hook that to the battery?

 

[surfpig]

Shoot. I know it's a great idea!

But how would it work?! Where would the device be installed to avoid interfering with essential components? Or would one just disconnect the hot lead, install a relay and hook that to the battery?

I had something like that years ago on my wife's car, she kept leaving the lights on... Saved many a battery. You had to reach in and reset it, then you could start the car.

 

[mct75]

So it seems like one can't install something like this at the battery??

Sure you can. There's two wires off the positive post (on mine at least), the starter motor and literally everything else (through the fusible links).

Starter motor pulls 100 to 500 amps and every ohm/volt matters. Do not try to switch it or mess with it.

Fuel pump, headlights, ECU, ARB fridge etc. all pull maybe 50 amps and they are not as sensitive. Note that 50 amps at 13.8 volts is 690 watts, so really not a lot of power to worry about interrupting.