Using DC directly from a battery when it's connected to a 6500EX-48

[boxvan]

I have two 24V DC fans (0.33A max each) and was wondering if it's a reasonable or more likely bad idea, to connect them in series with a switch and a fuse, and tap directly from an EG4-LL-48V battery or the busbars I have it connected to? Since there is a 6500EX-48 already connected to the busbars to charge and draw from the battery, would that cause a problem with any of those components? If I don't have to invert from 48V DC to 120V AC and then back through a DC power supply and lose efficiency each time, that would be pretty handy.

 

[Ampster]

That could work. Do you have some low voltage disconnect way to disconnect the fans? There are inexpensive voltage activated relays that could do that. You probably want to use the same LVD settings in your inverter or BMS, which ever is higher to give you some cushion.

 

[sunshine_eggo]

This will generally work provided the fans can operate at higher voltages as 48V batteries are usually in the low to mid 50Vs.

 

[boxvan]

That could work. Do you have some low voltage disconnect way to disconnect the fans? There are inexpensive voltage activated relays that could do that. You probably want to use the same LVD settings in your inverter or BMS, which ever is higher to give you some cushion.

That's a great idea thanks, I will probably do this!

 

[Ampster]

That's a great idea thanks, I will probably do this!

Also make sure, as @sunshine_eggo suggested, that your fans will work at the 50 plus volts of your pack. Most motors are fairly tolerant of some voltage differences.