[Amps] Plate transformer current unknown

[Steve Thompson]

> On 4/29/05 at 3:01 PM Angelo Karabetsos wrote:
> >I would like to find out the current rating of a transformer. Primary
> >voltage taps 0v-110v-115v-208v-230v and secondary taps  3450v-0v-3450v and
> >secondary resistance of 53.5ohms from 0v to 3450v tap and 107ohms from
> >3450v
> >to 3450v tap. All measurements done with a simple DMM. The commercial
> >amplifier it came out of has a plate current meter with a max reading of
> >600ma. How could I find out the CCS or ICAS rating?
> >Cheers Angelo
You can short the secondary with an ac ammeter and apply primary volts with a 
variac. Increase the secondary current in 100mA steps until the transformer 
is a hot as you are happy with - allow several hours for the temperature to 
stabilise at each current.

Assuming you are going to use a full wave rectifier and capacitor input, the 
CCS dc load current will be about 50% of the ac ammeter reading (that's based 
on my guess of primary resistance and calculations about your transformer 
from the Duncan Amps PSU designer prog.).

Steve