Electronic – Inverter not cutting off before deep cycle danger level

batteries

The documentation for my 400 watt inverter says the *inverter will shut down if the input voltage drops below 9.5V+/-0.3V

In the Deep Cycle Battery faq listed here:
http://www.windsun.com/Batteries/Battery_FAQ.htm (under "State of Charge")

it shows that my unsealed 85AH Costco deep cycle battery would be completely depleted at 10 volts, which is when my inverter would shut off. If this is correct, it would obviously harm the battery.

Does this mean I need to constantly monitor the voltage of the battery and cut it off manually? Get a better inverter where I can specify a cutoff voltage? Or is there some kind of extra cutoff attachment I can add to my setup? Please let me know if my logic is correct and what the best approach here to saving the life of my battery. Thanks!

*The inverter will operate from input voltage ranging from 10 volts to 15 volts. Optimum performance will occur when the voltage is between 12 volts and 14 volts.
If the voltage drops below 10.5V+/-0.3V, an audible low battery warning will sound. The inverter will shut down if the input voltage drops below 9.5V+/-0.3V. This protects
the battery from being over-discharged.

Best Answer

Inverted is set too low.

Battery will suffer.

Adjustment probably possible.

As it has got a shutdown system, worst case you can easily make your own monitor and tap into that point, probably. Worst worst cas is it's all done in softwrae with no hardware points in monitoring or shutdown that can be easily accessed. Impossible is nothing, but at some stage it's easier to replace the unit in some cases. Probably not here though.

Tell us more about the hardware integration level.
Do you have a circuit diagram?
Do you have a soldering iron? :-)