25-03-2012, 08:37 AM
(This post was last modified: 25-03-2012, 08:46 AM by Radio Fixer.)
I can add something to that Lawrence
One place that gives derating for transformers is the catalogue from RS Components Ltd and another is Hammond Transformers http://www.hammondmfg.com/pdf/5c007.pdf. Both quote 0.28 for half wave and 0.62 for a full wave bridge circuit, both into a reservoir capacitor. Basically this means that if the transformer is rated for say a secondary AC of 1A, into a resistive load, the DC current load for half wave, with filter capacitor input, can only be 0.28 X 1 = 280mA. The most efficient configuration was full wave, centred tapped, again into a reservoir capacitor, where the DC load current could be equal to the secondary current rating of the transformer.
Gary
One place that gives derating for transformers is the catalogue from RS Components Ltd and another is Hammond Transformers http://www.hammondmfg.com/pdf/5c007.pdf. Both quote 0.28 for half wave and 0.62 for a full wave bridge circuit, both into a reservoir capacitor. Basically this means that if the transformer is rated for say a secondary AC of 1A, into a resistive load, the DC current load for half wave, with filter capacitor input, can only be 0.28 X 1 = 280mA. The most efficient configuration was full wave, centred tapped, again into a reservoir capacitor, where the DC load current could be equal to the secondary current rating of the transformer.
Gary
