MERLIN NX ROOM CONTROLLER – INSTALLATION & COMMISSIONING INSTRUCTIONS
FREELY PROGRAMMABLE APPLICATIONS
All models can be used with freely programmable appli-
cations. The application engineer performs this task on a PC
on which COACH NX has been installed (see also cor-
responding Technical Literature listed in Table 13 on pg. 27).
The application supports a variety of actuators.
Analog 0(2)...10 V
6-way valve actuators
A variety of sensors (e.g., room temperature sensors, supply
temperature sensors, condensation switch, window sensors,
occupancy sensors, card readers, etc.) may be used to
optimize control quality.
Applications requiring a fast (20 ms) reaction time can be
implemented as event-based applications.
Blinds Function Block
The sunblinds may be used to control different devices:
Blinds: Height and slat angle.
Motorized drapes: Horizontal position of drape.
Motorized windows: Window position.
EmergencyCmd (highest prio)
ApplicationCmd (lowest prio)
Other useful inputs for special cases
Device Type, Hw Terminals, Runtimes,
SlatSteps, LockTime, ...
Fig. 18. Blinds function block
Manual Blinds Positioning
The blinds can be positioned manually using directly-wired
pushbutton inputs or by manual override commands con-
nected as input to the function block as programmed in the
wire sheet (e.g., manual commands received via BACnet
MS/TP). In the event of a conflict, i.e., when commands are
issued both by pushbutton and via BACnet MS/TP, the last
command received has priority and will thus position the
Manual Blinds Positioning by Pushbutton
Short press UP: Opens the slat angle by a configurable
slat angle segment.
Long press UP: Drives the blinds to the UP position.
Movement may be stopped by briefly pressing any blinds
Short press DOWN: Closes the slat angle by a con-
figurable slat angle segment.
Long press DOWN: Drives the blinds to the DOWN posi-
tion. Movement may be stopped by briefly pressing any
Configuration: Slat angle fully open = 80°, slat angle
fully closed = -80°, 4 slat angle steps (move the blinds
by 40° per step)
The slat angle is in the fully open position. The room
occupant positions the slats horizontally with two short
press signals. This is far more accurate than watching
the slats and releasing the pushbutton once the slats
appear to have reached the proper angle.
Energy optimization per EN15232 or special behavior of the
blinds can be achieved via the application input. The appli-
cation engineer can create customer-specific applications to
drive the blinds to the optimal position based on daylight
level, occupancy, heat/cool demand in the room, etc. The
application engineer may, e.g., create an application which
drives the blinds DOWN if the sun shines into the room and
there is a cooling demand for the room.
Application commands may be used by the supervisory
station or the primary plant controller to, e.g., drive all of the
blinds UP during the night.
The application engineer can program scenes for light, blinds,
NOTE: The application engineer has the option of blocking
application commands for a configurable time after
the blinds have been manually set.
The blinds function block has an emergency input which has
the highest priority. Application commands and manual com-
mands are blocked in case of an emergency command. The
emergency input is used, e.g., in case of strong wind, fire,
open window, or during window cleaning to block the blinds,
e.g., in the upper position.
Feedback Information from the Blinds Function Block
The blinds provide a feedback for the position of the blind. In
addition, they provide a cause for the actual position. This
information is of considerable assistance to the application
engineer in clearly understanding the cause for the blinds'
position (e.g., movement stopped due to open window).