low voltage cut off

[xcav8er]

so i recently upgraded the stock battery on my tt with 2 6v golf cart batteries and im looking for a simple and cheap low voltage cut off that will keep them from running below 12 volts. any suggestions?

[RoyBraddy]

There is a couple of good high current smart relays on the market... BLUE SEA and SURE POWER IND come to mind... Both of these solenoids (Relays) will monitor the 12VDC line and trip at the preset level you want to monitor for...

These are really designed to work in conjunction with your start battery circuit and when your truck alternator system goes into high voltage charging like 14.4VDC i.e. these solenoids will kick in and parallel your auxiliary batteries connections to be charged when the Truck start battery is being charged from the truck alternator system... When the truck alternator system is not in charging mode then it switches the auxiliary batteries out of the truck alternator system to keep you from ever running down your truck start battery.

You will need to read up on these smart solenoids application guides to see it they can work like you are asking about...

Roy Ken

[ve7fet]

Search for 12V Low Voltage Disconnect (or LVD). Cole Hersee (aka Littlefuse) makes some modules that are simple to interface to a large contactor (relay) to do what you want. Hi current contactors are also cheap... they are commonly used in pickup truck snowplow setups.

One thing to consider though, you may need 0.5-1A to drive the coil on the contactor to keep it energized... if you're counting watts... they are just burning up as heat.