eLECTRICAL gURUS

[rm41400]

250 HQI vs 400 PS

I have a 400 watt PS ballast made by PFO. On the ballast box it says it is 400 watts @ 3.8 amps.

I just bought a 250 watt HQi ballast and it is stamped 250 watts @ 5.5 amps.

I am confused about this. If the voltage supplied is fixed @ 110 (or 120) the output wattage should be as follows:

250 watt HQI 110volts x 5.5amps = 605 watts

400 watt PS 110 volts x 3.8amps = 418 watts.

Is this just the peak wattage at start up?

The main reason for this question is in regards to the heat generated by these lights. I assumed that my new 250 watt HQI ballast may be a little less intense and definately run cooler. However, I have observed just the opposite of this. They look brighter and the tank seems to be a little warmer than normal.

thanks!!!

I posted in the lighting forum but got no response

 

[cee]

5.5 A is correct for the open circuit current when no bulb is connected. It should state that on the label. My typical operating currents are about 2.6 A. These numbers apply for a M80 ballast, electronics should do slightly better.

Dave