Does the use of presence detectors affect lamp life ?

A

Presence detection, when used with fluorescent lamps, can have a negative effect on lamp life and in some cases control gear.

Fluorescent lamps have rated life based on a switching cycle of 3 hrs, during which lamps and control gear will have reached normal operating temperatures. More frequent switching can reduce lamp life significantly. To ensure rated lamp life is obtained we recommend a minimum on time of 20 mins.

Note, however, that many of the sensors and systems listed on the preceding pages offer features such as dim-to-off, as opposed to instant-off. With dim-to-off the time-delay could be set at 10 minutes, after which dimming starts with the final "off" taking place after a further 10 minutes. This maximises energy savings while keeping within the above recommendation of 20 minutes.

What happens to any of the lighting control systems featured here in the event of a power failure?

A

It depends on the system, because not all operate in exactly the same way:

Exodus receivers R025010, R025020, R025030, R025035 & R025040:

If the power interruption is very short (less than a few seconds), these units will revert to their former setting. If the interruption is longer than this they will revert to the off state when power is restored. However, they have a non-volatile memory so will not lose any scene information or other settings, regardless of the length of the power failure.

Installed on their own, fittings with Tridonic ECO control gear (switch dim or DSI operation) will all power-up into the 100% on state. This can be a substantial problem, and waste of energy, if the power cut occurs during a weekend. However, this situation will be avoided if an appropriate sensor from this catalogue is used. Then, when power is restored after an interruption the lights will switch on for a short time, then the sensors will take control and switch the lights off if no movement is detected.

Tridonic Excel one4all control gear has its own memory so will revert to its last setting after a power failure. However, this control gear is rarely used as standard, and it will anyway be over-ridden by any sensors or other control devices installed with it.

Digital Marshalling Boxes E016600 & E016620:

These have a non-volatile memory so remember all their configuration settings despite repeated power failures or brown-outs. Also, they are programmable so that individual lighting groups can be set to respond in different ways as power is restored after an interruption.

Sensors.

All the sensors listed here have non-volatile memory, so will resume normal operation after a power failure.

Does switching fluorescent lamps on and off frequently consume more energy than it saves?

A

The energy taken during starting is a small fraction of the energy used for one minute of normal operation. Therefore, switching fluorescent lamps off, even for a short period of time, will save more energy than the extra that will be consumed when they are switched on again.