In replying to a thread on LED fixtures, I did an experiment, and was somewhat surprised at the results. For an actual comparison, I used my new Kill-A-Watt, a "trueRMS" device.
A random 500W GE EHD lamp (of undetermined age):
Unplugged:
Volt: 124.9, Amp: 0.00, Watt: 000, VA: 000, PF: 1.00
Plugged into GPO (Australian term for General Purpose Outlet):
Volt: 121.1, Amp: 4.91, Watt: 596, VA: 595, PF: 1.00
A different 500W GE EHD lamp (of undetermined age):
Unplugged:
Volt: 124.9, Amp: 0.00, Watt: 000, VA: 000, PF: 1.00
Plugged into GPO (Australian term for General Purpose Outlet):
Volt: 121.4, Amp: 4.31, Watt: 524, VA: 521, PF: 1.00
For all examples above, VA=Vrms*Arms, and PF=W/(Vrms*Arms).
The question is:
A.) Do Stage/Studio Lamps vary that much in wattage right out of the box, i.e. Are manufacturing tolerances really that lax?
AND/OR
B.) Does the age of the lamp matter as to how much wattage it consumes, i.e. Does a lamp draw more (or less?) power as it ages?
I realize both are compound questions, so be specific in your answers. You may use charts and/or diagrams in your responses if you wish.
A random 500W GE EHD lamp (of undetermined age):
Unplugged:
Volt: 124.9, Amp: 0.00, Watt: 000, VA: 000, PF: 1.00
Plugged into GPO (Australian term for General Purpose Outlet):
Volt: 121.1, Amp: 4.91, Watt: 596, VA: 595, PF: 1.00
A different 500W GE EHD lamp (of undetermined age):
Unplugged:
Volt: 124.9, Amp: 0.00, Watt: 000, VA: 000, PF: 1.00
Plugged into GPO (Australian term for General Purpose Outlet):
Volt: 121.4, Amp: 4.31, Watt: 524, VA: 521, PF: 1.00
For all examples above, VA=Vrms*Arms, and PF=W/(Vrms*Arms).
The question is:
A.) Do Stage/Studio Lamps vary that much in wattage right out of the box, i.e. Are manufacturing tolerances really that lax?
AND/OR
B.) Does the age of the lamp matter as to how much wattage it consumes, i.e. Does a lamp draw more (or less?) power as it ages?
I realize both are compound questions, so be specific in your answers. You may use charts and/or diagrams in your responses if you wish.