UL 935:2001 pdf download.Fluorescent-Lamp Ballasts.
2.9 ELECTRONIC BALLAST- A ballast involving high frequency switching that is controlled by activecomponents (transistors, thyristors, and the like), and with the lamp ballasting impedance provided by aseries capacitive or inductive reactance appropriate for the high switching frequency. The lamps andballasting impedance may be connected either directly or by means of an isolating transformer to theswitching transistors.
2.10 FIXED BALLAST - A ballast intended to be permanently connected electrically.
2.11 INSTANT-START CIRCUIT- A circuit that employs a high open-circuit voltage to start lamps thatusually have a single contact at each end.
2.12 LEAD-LAG CIRCUIT- A two-lamp circuit that has one lamp in series with an inductor and theother lamp in series with a capacitor to attain a high power factor. Generally, it may be part of either aninstant-start or preheat circuit.
2.13 LIVE PARTS - Metallic parts intended to carry voltage or current. A part that is connected to agrounded (neutralj supply conductor is determined to be a live part.
2.14 MEASUREMENT INDICATION UNIT (MIU) - The output voltage across the meter, in millivoltsRMS, in the measurement instrument in Figure 23.2, divided by 500 ohms. The instrument indication isequal to the RMS value in milliamperes when the frequency is 60 Hz (sinusoidal current).The readingis not always a direct indication of the RMS or other common amplitude quantifier of leakage currentwhen the leakage current is of complex waveform or frequency other than 50 or 60 Hz.
2.15 POWER CAPACITOR - A capacitor that is connected:
a) ln series with a lamp or lamps and provides the ballast impedance for the lamp current; orb) Across the input leads of the ballast or across an extension of the primary winding forpower-factor correction.
