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Steve Walker[_5_] Steve Walker[_5_] is offline
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Default Drill charger diagnostics

On 18/05/2019 14:50, ARW wrote:
On 18/05/2019 14:39, D.M. Procida wrote:
Dave Plowman (News) wrote:

In article
,
Â*Â*Â* D.M. Procida wrote:
I have an old B&D cordless drill; the batteries don't charge.

Either the batteries or the charger are faulty.

I've opened up the charger. At the input of the transformer, I measure
240V. At the output, 0V (I'd expect 18V or so).

I assume this means that the transformer itself is broken - at least, I
can't think that anything in the circuit after the transformer could be
responsible.

I haven't desoldered the transformer from the circuit board, but I
guess
that would be a way of being sure.

Is that correct?


No LEDs, etc to tell you what is going on?


The LEDs (charging, fully-charged) are both off. There is no voltage at
the charger's output, which is why I opened it up to find out if I could
where the fault is.


I would not expect an output from the transformer unless there is a load
on it. And the load would be detected by the components on the PCB.


Unloaded transformers give a much higher output voltage than their
rating, only falling into the normal range when loaded.

SteveW