
MLS Digital Mid-Bay Detector
MLS2001DMBF & MLS2001DMBSM for DSI ballasts
MLS2001DALIMBF & MLS2001DALIMBSM for DALI ballasts
MLS2001DMBF
MLS2001DALIMBF
MLS2001DMBSM
MLS2001DALIMBSM
Installation and Commissioning
Instructions
Note: HP2000 required for commissioning

MLS Digital Mid-Bay Detector: MLS2001DMBF/SM for DSI & MLS2001DALIMBF/SM for DALI ballasts
Only suitably qualified personnel should install this equipment.
Fixing
Flush Version: Depth required behind ceiling: 62mm from front flange plus an allowance for the minimum bend radius of
the cable. Sinking box fits into a 89mm diameter hole in ceiling tile or plasterboard ceiling. Note: If the sinking box is being
fitted to a hard substrate such as metal, increase the hole size to 91mm. To avoid damage to ceiling tile, do not overtighten.
No access above the ceiling is required.
Surface Version: The housing may be secured to a hard surface or a BESA box. The unit fits into the housing with a simple
bayonet action.
For aisle or corridor applications, there is
an optimum orientation for approach:
Centre
of facet
Path of optimum
sensitivity
Align to arrow
5
1 °
for optimum
sensitivity
Note: When operating in 'Regulating Photocell' mode, a closed feedback loop is formed by the luminaire, the reflective
surface beneath, and the photocell. For this control loop to function correctly, the photocell must have a good view of the
reflected light only from the luminaire(s) under its control – NOT from adjacent luminaires not under its control. This means
that the higher the detectors are mounted, the further apart they must be in order to ensure that they see mostly 'their own
light'. Therefore, it is recommended that detectors are mounted on a pitch not less than 50% of the mounting height when
using the regulating photocell function.
Connection
Control of a group of luminaires is achieved via the detector’s two-wire digital control circuit. Each luminaire to be controlled
must contain a digital regulating type ballast with the appropriate DSI or DALI input. Ballast types must not be mixed.
Connect all ballasts in the control group (max 25) in parallel and also to the polarity-free digital output of the detector.
Each luminaire is controlled completely by its digital input and therefore would normally have a permanent power supply. If,
however, it is desired to have manual wall switches, any or all of the fittings in a controlled group may also be controlled in the
traditional way - by turning off the power. The control circuit will continue to operate properly even if some of the luminaires in
the group have had mains power removed.
The MLS Bus must be connected to the MLS Bus Network. An MLS Bus Power Supply is required for each network of up to
200 MLS devices. Refer to the MLS Bus Power Supply Installation Instructions before commencing any bus wiring.
It is imperative that the MLS Bus is wired in the correct type of cable. Normally this will be 1.5mm² unscreened twisted pair.
See Application Note AN4001 for details.
Do not connect mains to the MLS Bus wiring
‘OneSwitch’ Dimming
OneSwitch dimming affords local control to the end-user whereby a simple, momentary, push-to-make wallswitch can be
used to raise or lower the lighting level or to toggle the output ON/OFF. A short press of the switch (less than 1 second) will
toggle the output status while a longer press will raise or lower the output. Each time the switch is pressed, the direction of
dimming reverses. If the switch has not been pressed for 5 seconds, the direction will be up (brighter) - unless the output is
already above 90% in which case the direction is down. If the switch is held continuously, and the output reaches maximum,
the light output will remain at this level until the switch is released - a latching switch may be connected in parallel allowing
the occupancy detection to be overridden on (Note: If the initial direction was down, when the output reaches minimum it will
ramp back up automatically).
Setting the Regulating Photocell
This product is intended for use with high frequency regulating ballasts with digital control inputs. An infrared programming
tool, the HP2000, is required for programming the regulating light level set point.
Using the HP2000 Programmer, enter the Utilities menu and select ‘Set Light Level’. Use the ‘up’ and ‘down’ buttons to
manually adjust the light output from the luminaire(s) and when at the required level press and hold ‘OK’ to store. The
luminaire(s) will blink to acknowledge a successful store operation.