[Amps] AL1500 PSU design

[f6irf at free.fr]

> Someone asked if you could be putting 240V on a 120 winding
> through a wiring error, and indeed you could be doing that.

Tom,
The first thing I did after the first bang was to check the transformer. I found
that it was wired for 220V, I rewired it for 240V according to the manual
indications (I have around 235V +/-5V at home), and checked the transformer
alone using a HV-probe 1st (*), then a voltage divider made of 4x1Mohm
resistors. The AC voltage was found conform to the expectations (around 2320V
AC- if I remember correctly, with the primary wired for 240V - of course subject
to resistance tolerance)- that should make around 3280 DC without load - isn' t
it?  And of course I checked more than twice that the wiring was conform to the
manual indications...

(*) the HV probe is a 1/1000 commercial model; associated with a digital
multimeter, it measures correctly the mains value, but while connected to the
transformer secondary, it was giving highly fluctuating indications - I guess
due to the important magnetic field around the transformer. It is why I tried
with the voltage divider and an analog multimeter (40,000ohm/V - 1500V AC) my
digital multimeter being limited to 500V AC.






Quoting Tom W8JI <w8ji at w8ji.com>:

> Patrick
>
> Someone asked if you could be putting 240V on a 120 winding
> through a wiring error, and indeed you could be doing that.
>
> That was a good suggestion!
>
> Be sure you do not have a wiring error that is applying too
> much voltage since the dual primary has two 120V windings,
> one with a 100V tap.
>
> 73 Tom
>
>
>