In message <BE26154279EFD1119FDE00A0C9410EC2263DAE@excalibur.swindon.msl
.mitel.com>, Peter Chadwick <Peter_Chadwick@mitel.com> writes
>
>further to G8WRB's comments,
>
>> The lowest primary resistance (lots of probe digging and
>> twisting) reads ~1.5 ohms
>
>This may well not be the 115v primary, but a part of the primary winding.
Hmmm - I didn't read the original posting properly, in too much of a
hurry. The 3kVA transformer I got for G3RZP had a primary resistance of
<0.2 ohms for 240V winding, which makes much more sense when coupled
with G8WRB's analysis. From memory, I think that the copper and iron
losses were around 80W each.
I've seen odd resistance measurements with autoranging meters when the
dV/dt upsets the reading when the range switches; high Z dvms might be
particularly prone to this. It might be worth using a bench supply and
running 100mA dc through it.
If the resistance readings are correct, it will fry for sure with a
capacitor load. Cook your burgers while you drink the beer.
Steve
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