20
RICKARD 2019
MLM INTEGRATION WITH BMS
Occupancy control override operation
Working Hours
When the room is vacant for a specific period, the diffuser(s) in that particular zone will drive to the minimum
closed position. This period is user adjustable as ‘delay 1’ in the MLM Tool application. Should a second vacant
period, as set in ‘delay 2’ elapse, the diffuser(s) will drive to the fully closed position. The factory default on both
these timers is set to 15 minutes.
If the room temperature drifts outside the temperature band during this state (set in Process/Setpoint/Backoff
Band), the diffuser(s) will revert to the minimum closed position.
If occupancy is detected during this control override operation, the diffuser(s) will revert to normal operation.
After hours
After hours operation is basically the same as for working hours. Delays 1 & 2 are the same for both. The only
difference is the ‘After hours backoff band’ is used for phase two of the unoccupied control. The RTC operation
for after hour detection is described in the RTC control override section.
Note: If an On-board master unit is used to control a zone, no distinction is made between working hours and
after hours and only the ‘Backoff-band’ parameter is applicable, as the On-board master does not contain a Real
Time Clock.
System set-up for Occupancy Sense
The user can adjust the unoccupied period before the system reverts to a control override state. The following
procedure needs to be followed to set the system up:
Diffuser controller
Ensure an Occupancy sensor is fitted to the Diffuser controller hardware or to the Wallstat hard-
ware.
Select the Diffuser controller (type code 10), go to Setup menu, Occupancy present and check the
Occupancy present box. By setting this parameter that particular diffuser is enabled for occupancy
sense.
A Wallstat unit containing an occupancy sensor does not require an occupancy present setup and is
always enabled for that zone.
The sensor sensitivity can be changed for a value between 1 and 10 to offset false or no triggers.
The default setting ranges between 6 and 8.
