Basic Documentation

Overview
Integration via Modbus
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A6V12114068_en--_c
– External room temperature sensor or return air temperature sensor
– Automatic heating/cooling changeover sensor
● S1 input freely selectable for (RDF660MB/MM only):
– Window contact
– Presence detector
– Hotel keycard
● 2 multifunctional inputs (X1 and X2), freely selectable for (RDF660MB only):
– External room temperature sensor or return air temperature sensor (AI)
– Automatic heating/cooling changeover sensor (AI)
– Window contact (DI)
– Dew point sensor (DI)
– Electric heater enabled (DI)
– Fault input (DI)
– Monitor input (DI)
– Monitor input (AI)
– Automatic heating/cooling changeover sensor (DI)
– Presence detector (DI)
– Hotel keycard (DI)
● Advanced fan control function, e.g. fan kick, fan start, selectable fan operation
(enable, disable or depending on heating or cooling mode)
● Purge function together with 2-port valve in a 2-pipe changeover system
● Reminder to clean filters
● Floor heating temperature limit
● Reload factory settings for commissioning and control parameters
● User and parameter settings can be retained with power loss and operating
mode can be returned to previous operating mode, Comfort mode or Protection
mode (depends on P27)
● RS 485 Modbus (terminals +, - and REF) for communication with Modbus
compatible devices
● Display on a secondary line: room temperature, outdoor temperature or time of
day via Modbus
● Mounting on both round and square conduit boxes, 60 mm fixing centers
2.3 Integration via Modbus
The RDF660MB... communicative thermostat with Modbus open protocol on RTU
(Remote Terminal Unit) mode enabling easy integration into BACS via RS485.
The following Modbus functions are available:
● Central controls of room operating modes, setpoints, fan speed and fan mode
● Remote monitoring e.g. operating mode, control outputs, temperature sensor or
switch, etc.
● Alarming, e.g. external fault contact, condensation, clean filter, etc.
● Outside temperature or time of day via bus displayed on thermostat
● Key lock
Engineering and commissioning can be done via:
● Local DIP switches and HMI
● Modbus commissioning tool