[TR] Trickle Charger Wire Gauge?

[Dave1massey at cs.com]

In a message dated 10/18/2009 12:29:58 PM Central Daylight Time, 
paulwillou at socal.rr.com writes: 
> Will automotive speaker wire be sufficient to handle the current of the 
> inexpensive Harbor Freight automatic battery chargers?
> 
> I'm going to install a quick disconnect in the grill so I don't have to 
> open 
> the hood to connect the battery charger.  I've got a roll of red and black 
> 
> speaker wire that would make a nice clean installation.  But after 
> stripping 
> the insulation off, it doesn't seem like a lot of wire.  But then I 
> imagine 
> that there isn't a lot of electricity in that little charger either.
> 
If you are talking about one of those 1/2 amp "Battery Tenders" then just 
about any speaker wire will suffice.  The small end limit on speaker wire is 
about 20 or 22, much smaller and it gets too fragile for most hobbiests.  
This will carry 1/2 amp with ease.

I've never cut into one of these "Tenders" but I'd bet a beer (and I'n not 
talking an Old Milwaukee or Coors light, but a good Old Speckled Hen ofr 
Belhaven Twisted Thistle) that it has an IC voltage regulator (LM317 or the 
like) with active current limit and will limit to 1/2 amp even if shorted.  
You'd have to be pretty clever to make one of these start a fire.  Maybe if you 
used a blasting cap to make the connection.

If you are using a larger unit (eg: 5 Amp) you would want to use larger 
speaker wire or 16 gauge zip cord from the hardware store.

Dave