ii) The Primary Interest is the Switching Control Output
With the photocell configured as ACTIVE or PASSIVE:-
1) If the lights are not already on, switch them on manually by pressing ‘UTILITIES / LIGHTSPOT/MLS/LCM /
IR-REMOTE / HC5 / Lu / OK’ (QuickSet Pro) or "+" (HC5A). Fluorescent lights do not reach full output
until up to 15 minutes after being switched on, so ensure that the lights are fully warmed up before continuing.
2) Wait until the time of day when the natural light level is at the point below which you
would
want the lights to
be on, and above which you
would not
want the lights to be on.
3) Start the internal self-programming mechanism by pressing ‘UTILITIES / LIGHTSPOT/MLS/LCM / SET
LIGHT LEVEL / OK’ (QuickSet Pro) or Scene 1 (HC5A). The detector takes a photocell reading, adds a small
amount and stores the value in SET-POINT HIGH. Then it turns the lights off, makes another measurement
and stores the value in SET-POINT LOW. The lights now switch on again to acknowledge a successful
programming operation.
The two switching thresholds have now been set, and the difference between them is equal to slightly more
than the contribution made by the electric lighting. This is the perfect amount of hysteresis to ensure that the
lights will not oscillate.
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