Data Sheet for Product

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Building Technologies Fan-coil controller for wall mounting ACR12 CE1N3578en
HVAC Products 03.10.2005
Electric heater
The REF7090521, REF7090523 controllers have a relay built in for directly controlling
an electric heater. The REF7090520, REF7090522 controllers need an external relay
with a 230V coil for this purpose. Note that this relay is not included in the delivery.
The controller must be configured as a 2 pipe controller (P09 = ON or 1).
The controlling of the heater depends on the control deviation (pulse duration modu-
lated). The P-band of the electric heater is as following:
− 2 K if P05 = ON or 1 and the change-over on cooling
− 4 K if P05 = OFF or 0 and the change-over on cooling
− 0.4 K if P05 = ON or 1 and the change-over on heating
− 0.8 K if P05 = OFF or 0 and the change-over on heating
The cycle time for the pulse duration modulation is fixed at 240 s. If an external relay is
used, then it must be dimensioned for being switched every 240 s.
For safety reasons, the heating output is limited to max. 50 % at manual fan speed I
(relay 120 s "on" and 120 s "off"), to max. 80 % at speed II and unlimited at speed III.
Parameters
Various parameters define the behaviour of the controller. These parameters are de-
fined by 12 DIP switches (in controllers without display) or by entering the values in the
parameter mode (in controllers with display).
The first 12 parameters (P01...P12) are identical in both types of controllers.
E.g. P01 corresponds to DIP switch 01and "P01 = 1" in the text of this document refers
then actually to "DIP switch 01 = ON".
For safety reasons, always switch off the controller before opening the housing and
before manipulating the DIP switches. Changes of the DIP-switches are only valid after
a power-on reset.
Entering the parameter mode of controllers with an LCD display and setting the pa-
rameters is achieved in the following way:
C/O
Fan
Plus
Minus
•
Press simultaneously the keys <C/O><FAN><MINUS> until the display gets
dark (after about 2 to 4 seconds).
•
Press <MINUS> 2 times at an interval of about 1 second.
•
Press <C/O> until P01 appears in the LCD display.
•
With the <PLUS> or <MINUS> key, select the parameter you want to see or to
modify.
•
Press the <C/O> key to see the actual value of the parameter.
•
Change the value by using the <PLUS> or <MINUS> keys.
•
Press the <C/O> key to enter a modification or the <FAN> key to cancel the
modification.
•
Incrementing Parameter numbers and values is accelerated when the + or –
key is depressed for more than 2 seconds.
•
To return to normal operation, press the <FAN> key.
Important note