Main Voltage
– Rated input voltage for the ballast
Watts
– Input power
Amps
– Input current, or draw
Power Factor
– A measurement of how effectively the ballast con-
verts electrical current to useful power output, in this case, output
to the lamp. Power factor is measured between 0-1, the closer you
get to 1, the more effective the circuit is said to be. The Phantom’s
power factor is greater than .98.
Working Voltage
– The acceptable operating range for input volt-
age to the ballast. Deviations from the rated numbers may result in
decreased ballast performance and additional case generated heat.
Ignitor Voltage
– Ballast output during ignition sequence.
THD (Total Harmonic Distortion)
– A measurement of all har-
monics present in a circuit. The higher the number, the more stress
is applied to internal parts, the lamp, and the power grid. Gener-
ally, a number below 10% is considered desirable in an electronic
ballast application.
CF (Crest Factor)
– A measurement of how “clean” the ballast
power output wave is. A perfectly clean output sine wave would
have a CF of 1.414. Given that some harmonics must exist in
an electrical system, the crest factor must always be higher than
1.414. Therefore, the closer the ballast is to a CF of 1.414, the
easier it is on the lamp.
ta (Ambient Temperature)
– Maximum rated ambient tempera-
ture for the ballast area. Excessive ambient temperature can result
in ballast failure, safety shutdown, or lamp failure.
tc (Case Temperature)
– Maximum temperature that the case of
the ballast should reach. If the case temperature exceeds this number,
the ballast may be malfunctioning, or the ambient temperature may
exceed the rating.
Definition of Terms
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