Setting the Photocell
1. If the lights are not already on, switch them on manually by pressing ‘Utilities/User Remote/Lu/OK’
[HP2000] or ‘On’ [HP18]. 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. This stage may be omitted if the intention is to
operate the detector’s photocell in Passive Mode only [the detector must have already been programmed to
Passive Mode].
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/Set Light Level/OK’ [HP2000] or ‘Set’ [HP18].
The detector takes a measurement, adds a small amount and stores the value in the Upper Threshold. Then it
turns the lights off, makes another measurement and stores the value in the Lower Threshold. 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 the contribution made by
the electric lighting; this is the perfect amount of hysteresis to ensure that the lights will not oscillate. The thresholds
may be read back and fine-tuned if necessary using the HP2000. Please note that the values are non-specific units i.e.
not lux.
Note:
The light level perceived by the detector at the moment immediately prior to a Download operation is shown
momentarily on the HP2000 screen following the Download; this is a useful mechanism for troubleshooting.
Lights ON =
Lights OFF =
Upper Threshold
Lower Threshold
Natural
Light
Level
Duration of
Off Delay
Note that when the natural light
level exceeds the ‘upper threshold’
value, the lights do not immediately
turn off. They will turn off only when
the upper threshold has been
exceeded for the duration of the
programmed Off Delay.
Active Mode
Passive Mode
Occupancy
Area Occupied =
Area Unoccupied =
Technical Data
OPERATING VOLTAGE: 230V 50Hz (UK & Europe)
RECOMMENDED CIRCUIT PROTECTION: 10 Amps
MAXIMUM LOAD: 6 Amps
MAXIMUM RECOMMENDED MOUNTING HEIGHT: 12 metres
o
RANGE: 360 cone-shaped detection pattern.
Diameter at floor level (d)
= 1.75 x mounting height (h)
MINIMUM MOUNTING PITCH (SPACING): 0.5 x mounting height (when utilising the photocell - see note under ‘Fixing’)
PHOTOCELL: Adjustable 50-5000 lux via HP2000/HP18
OFF DELAY: Adjustable via Programmer - factory pre-set to 20 mins
Options: 1 min - 96 hours / Disabled (via HP2000); 5, 10 or 20 minutes (via HP18) - plus 10-second Walk-test
COLOUR: White
MATERIAL: Flame retardant PC/ABS
WEIGHT: 70g approx (excluding cable)
IP RATING: 4X (Estimated - not tested)
o
o
OPERATING TEMPERATURE: 0 C to 40 C
h
d
