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Re: Low Voltage Lighting



SQLit wrote:
||
|| If you looking for mood lighting consider switching the lights at
|| full bright in several stages. A dimmer accepts the full load and
|| only passes on the level you set. Using a 100 watt base and you set
|| it for 50 % or 50 watts then your burning off 50 watts in heat. Not
|| exactly efficient. I know it means more wiring but if you think
|| about it you might decide that it is a better way to go.
|| Just a wild thought from the cheap seats

You're wrong, to have half power you will need V_half_power=0.707V_full, the
resistor would only need to dissipate 0.293Vfull at 0.707*Ifull=20.7W if the
lamp had 100W. This assumption is for pure resistive and linear loads.
In reality an incandescent bulb will reduce the heat and its resistance, so
you need a little less voltage and more current for this, but the resistor
will not need to dissipate more than 25W when the bulb puts out 50W. Got it?
-- 
ciao Ban
Bordighera, Italy
electronic hardware designer





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