Care must be taken to orient the lamp correctly in T5 luminaries equipped with Power Sentry (PS) battery backup systems. In the battery backup operation mode (lower light output emergency mode) the lamp operates much cooler than in the full power normal mode. The new ECO (“Green”) type T5 lamps have very little mercury in the lamp which decreases the low temperature performance of these lamps. The design of these low mercury Eco-friendly and amalgam FL lamps, makes the label end of the lamp (lamp filament is further from the lamp socket at this end) more sensitive to this lower temperature. If the lamp is not oriented correctly the lamp can get very pink and dim within 10 minutes in emergency mode.
The drive waveform from the Acuity Brands Power Sentry is designed to compensate for this lower operation point. With this drive circuit, the end of the lamp that connects to the red lead from the Power Sentry unit will operate warmer than the end connected to the yellow wire. When a Power Sentry system is used with a T5 lamp the luminaire should have a label placed where the lamp is inserted into the lamp socket telling the assembler, and end use service person, to orient the lamp with the printed label in the desired direction. The luminaire needs to be assembled with the red PS wire connected to the lamp socket at the lamp label end. If the lamp is not oriented correctly the lamp can get very pink and dim within a few minutes
If an assembled system is operated in emergency mode for less than 10 minutes and the T5 lamp gets very pink at one end then the first thing to try is to reposition the lamp with the label at the other end of the luminaire.