Intelligent drill battery chargers

[David WE Roberts]

Sometime last year I established that the charger for my 18v Site combi drill should also (because it was intelligent) charge my 12v batteries for my two B&D drills.

Looking inside the Site CA18 charger body there are +ve and -ve terminals plus 3 other terminals, two of which match metal contacts on the battery.

I was hoping just to construct a pair of leads to go between the charger and the +ve and -ve terminals on the B&D batteries.

Does anyone know what these extra contacts are for?

Cheers

Dave R

[Bob Minchin]

They provide the intelligence and possibly a safety mechanism. Probably a temperature sensor and maybe a tap part way up the battery stack would be my guess.

Bob

[David WE Roberts]

I can believe temperature sensor because there are a couple of extra contacts on the B&D batteries as well (or can you get a B&D intelligent charger for these batteries?).

AFAIK some intelligent chargers don't need extra contacts - at least the one doing my car battery and the one doing my AAA batteries both claim to be intelligent and both only have two contacts.

If they are necessary then presumably I have to map the extra contacts across between the B&D battery.

If I can find what they all do.

Cheers

Dave R

[John Rumm]

I would assume the Site charger is the same as the Makita one. i.e. similar to

so, then I can confirm its happy to charge packs without the extra contacts.

Temperature sensor usually.

Without connection to these, the charger will run in normal peak detection mode.