Charge an emergency fan on AC or DC setting?

[t3rom]

I've an emergency fan with an AC/DC button on it, but its manual doesn't say on which setting it should be charged. I've tried charging on both settings, and it can be charged either way.

On the back of the fan it reads:

"AC 220/240
50/60Hz
19w"

The fan's box only says:

"DC: Operate when power failure.
AC: Operate by AC power directly"

My question is on which setting (AC/DC) I should charge it for future use when there's a power failure? Thanks in advance!

This is not a homework question.

 

[Baluncore]

The AC / DC switch probably selects the source of power for the fan motor.
So it does not matter which is selected during charging of the internal battery.

 

[t3rom]

I see. Thanks for the reply!

 

[Windadct]

Also -the switch is most likely "after" the battery, so it has no effect on the charging circuit.

 

[Sindhutammu]

I agree With Mr. Baluncore. The Switch itself selects the Power source(whether AC/DC). No matter on Battery charging.

 

[jim hardy]

That's assuming the charger's current capacity is more than the fan draws.
It could be a trickle charger.

Knowing no more than has been posted, I'd charge it on AC setting.

But one experiment is worth a thousand expert opinions...
Try it overnight - run battery down and then see whether it'll charge back up with fan running in DC position ??

 

[dlgoff]

I would just take it apart and have a look. The wiring should be straight forward.

 

[t3rom]

But one experiment is worth a thousand expert opinions...
Try it overnight - run battery down and then see whether it'll charge back up with fan running in DC position ??

Well, I did that and it does charge fully on DC position. I'm also drawing this conclusion that the AC/DC button has nothing to do with the battery.

 

[t3rom]

I would just take it apart and have a look. The wiring should be straight forward.

That's actually not a bad idea. I'll do that even though I understand the AC/DC option has no effect on the battery.