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Rich256

wrote:
Rich256 wrote:
wrote:
wrote:

I have a Black & Decker PS160 charger - 12V. It stopped working, so I
opened it up to have a look. There are only 2 resistors in these
things. One of the two resistors has blown, probably because I left the
unit plugged in for too long and ruined one of my batteries.
If you bought the original with a credit card, it's possible the
original warranty was extended by an extra year. Or can you buy a B&D
tool that uses an identical charger and look at it?

If a resistor blew, I would expect the power transistor or triac
associated with it to have blown as well. I hope it's a discrete part
and not built into an IC.
Those chargers usually don't use transistors or traics. Just a
transformer, diode bridge and sometimes a dropping resistor.

I admit I've never seen the inside of a B&D charger, only DeWalt and
Ryobi units, but unless the battery pack contains some extra circuitry,
which I doubt it does, being a budget brand, a fast charger built like
that will be rough on the batteries.

I also doubt that it could be called a fast charger. Most of them the
transformer output is just enough to charge if left on long enough.
Similar to those battery operated devices that tell you to charge for at
least 10 hours before using.

A burned resistor I would guess could be due to a shorted cell in the
battery pack. Important to measure the battery voltage before doing
anything else. The pack has 10 cells. If the voltage doesn't get to
near 12 volts or is below 10 a cell is probably shorted.

I just looked it up and see it is a 12 volt charger. Uses a wall plug
transformer. And see others commenting that there is only two resistors
and they have the same problem of one burning out.