Will running an AC motor directly from a 52v battery hurt the battery/BMS?

[Stu Summer]

I have several 52v batteries. I have some AC tools that will run directly from the batteries but I haven't done it much because I am afraid I will hurt the battery or BMS in some way. The tool I especially want to use is a AC 110v 6A angle grinder. Will doing so hurt the batteries? I just made an AC female plug to a XT60 male adapter.

Thanks!

Stu Summer

 

[kansas]

Well none of the better experts have shown up so I will dive in. Mostly, need more info.

AC motors will not run on DC. At all. You say you have done it, please say exactly what you have done. What tool, what motor type, with what result.

Many tools use AC/DC or "universal" motors. These will run on either, but require the same voltage whether AC or DC. Are you saying you have run your 110V tools on 52V? If they have AC/DC motors, they might run on 52VDC, but not very well. Most tools will state on the nameplate if the motor is AC or AC/DC.

If you put two 52V batteries in series, that would probably run a tool with a 110V AC/DC motor acceptably, but not at full power as the voltage is a tad low. I do not see that it would hurt the battery as long as the load (amps) is within the battery capacity. Or the BMS.

 

[goatman]

j mantzel

https://www.youtube.com/watch?v=6uLM7-KYwHo

 

[mulp]

The cells will probably be fine, but the BMS might be fried by EMF spikes from the brush motor you are driving. BMS design might include protection from back voltage spikes as carry over from other power control/protection in power semiconductors. Might.

I'd consider capacitors plus the kind of over voltage protection used to protect against "lightning strikes" with a small ohm high current resistor, say several feet of 20 gauge copper wire wrapped around a stick, or steel bolt? aka inductor, to protect the BMS.