Battery terminals nut & bolt size?
I plan on connecting Power Inverter in the trunk of my E-430, but don't know which cables to buy because I need to know the correct nut and bolt sizes(in inches) for the battery terminal. The primary one I'm considering is this one:
...however they only state that the ring terminal size is available in either 5/16" or 3/8". Which of these terminal sizes will properly fit around the battery terminal bolt without being too tight or too loose?
Any help would be greatly appreciated, thanks.




MB is using 2 sizes of bolts on battery clamps, so check what you actually have.
The bigger bolt, having 13 mm head is 8 mm.
The smaller one with 10 mm head is 6 mm.
Hope you can convert mm to inches?
For permanent installation you need to add breaker/disconnect switch. Inverters do have big parasitic discharge.
Don't forget good ventilation.




With internal switch I would double check. Usually they kill the electronic side of inverter, while leaky 12V side will keep on drawing from the battery. Not o problem on daily driver, but if one time you leave the car for few days you might have unpleasant surprise. I am caution about the "low voltage shut off" as those are usually set to save the battery from destruction, not necessary leaving charge for engine start.
The best would be high-amp relay that would activate with ignition on, or a timer if you want to use inverter with engine off.
Last edited by kajtek1; Apr 22, 2017 at 07:25 PM.


