TLC-FCR-T Engineering
Control Functions
The controller is designed to control fan coil systems with up to three fan speeds and one spring return valve. The fan
speeds may be controlled to run manual or automatic. In automatic mode, the controller will change fan speeds
according to the temperature difference of room temperature and setpoint.
Setpoint
•
Minimum and Maximum Set Point Limits: Limits the adjustable range of the loop set point. The limits for
heating and cooling sequence may be chosen individually.
Control Sequence
•
Standby set point shift X
SBY
: This function shifts the set point while the operation mode is standby. The
heating set point W
H
is reduced and the cooling set point W
C
increased by the value of the standby set point
shift X
SBY
..
•
The switching span for cooling and heating determines the temperature difference required for the fan
speed to increase to the next level.
•
Switching Hysteresis defines when a fan speed change is reversed. The aim is to avoid unnecessary
switching of fan speeds and thus to increase the life span of fan and relays.
•
Mold Protection. The fan will not stop when the setpoint is reached while this parameter is activated. This
way the room will still be ventilated although there is no need to vary the temperature. The valve will still be
controlled according to temperature need. Mold protection should not be used for fan-only systems!
•
Delay OFF: Prevents a too short running cycle for the heating or cooling stage by setting a minimum running
time. Delay OFF applies to all heating and cooling stages.
•
Delay ON: Prevents a too short stopping cycle for heating or cooling stage by setting a minimum stopping
time. Delay ON applies to all heating and cooling stages.
•
Step by step switching: In order to reduce the startup load of large fan motors, fan stages will be switched
on and off step by step, going through low and medium before activating high fan speeds.
•
Fan Off delay: In case heating or cooling has been active and the unit is switched off or reached the set
point, a 60 seconds fan off delay is activated to prevent over heating of a heating stage or condensation on a
cooling coil
•
External Input Functions: The external input may be configured as external temperature control input or
as binary input. The external temperature input can replace the internal sensor as control input or detect heat
cool modes if auto-change-over is enabled. If in binary mode it may be used to toggle Comfort and Standby
modes, comfort and off or heat/cool modes. See auxiliary functions below for more details.
•
Activation Delay: Defines the delay the binary contact has to be open before off or standby mode is
activated.
Fan Medium
Cooling Mode
Heating Mode
Fan Low
0
X
FH
W
H
X
FC
W
C
Fan High
H
F
Mold protection
ON
Coil
T [K]
T
Room Temperature
w
H
Setpoint Heating Mode
X
FH
Switching Span Heating
w
C
Setpoint Cooling Mode
X
FC
Switching Span Cooling
H
F
Hysteresis
TLC-FCR-T, V2.0 22.03.2007 HRW Limited Subject to alteration Without Notice
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