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#129103 - 07/26/04 04:05 PM series circuit's
james S Offline

Registered: 05/13/03
Posts: 102
Loc: West England
In a series circuit which is supplied by constant current regulator at 50 HZ(keeps current at 6.6 amps no matter what load is introduced or taken away with respect to the size of regulator),and consists of many 1:1 transformers with there primary winding connected in series with the circuit loop, the secondary having a lamp with the necessary current rating (matching the series circuit current rating)and the same wattage rating as the transformer it is connected to.

my question this,

if i was to insert a lower wattage lamp (50W) on the secondary side of a 100W transformer, would there be 100W being produced by the lamp?

The way i understand it is the lamp takes the necessary VOLTAGE in this case, and the constant current, which then produces the rated wattage of the lamp.

If my understanding is correct, would this leave the overall series circuit a little more inductive due to the full rating of the secondary not being used resulting in a inductive reactance on the primary.?

sorry to go on!!!!!!

#129104 - 07/30/04 03:57 PM Re: series circuit's
Trumpy Offline


Registered: 07/05/02
Posts: 8532
Loc: SI,New Zealand
Please bear in mind that a 50W lamp will never dissipate 100W of energy, not matter what it is connected to.
The current drawn by a given size of lamp, is based on the resistance of the lamp filament, the higher the lamp resistance, the lower the current drain on the supply.
Also, with regard to transformers, you can never draw the full nameplate wattage (VxI) from a transformer, because they have a certain "loss factor", caused by Iron losses, Copper losses and Hysteresis losses.
Let's face it, these days if you're not young, you're old - Red Green grin


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