TLC-FCR-2 Engineering Manual
Doc: 70-00-0081, Date: 20081219
© 2008 Vector Controls Ltd.
Page 9
Control Functions
The controller is designed to control fan coil systems with up to three fan speeds. 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
•
4-pipe or 2-pipe system: 4-pipe systems use one heating and one cooling stage. Heating and cooling mode
will switch according to demand. A delay is implemented to prevent unnecessary switching between heating
and cooling mode: Heat – Cool change over delay.
•
Economy set point shift X
SBY
: This function shifts the set point while the operation mode is Economy. The
heating set point W
H
is reduced and the cooling set point W
C
increased by the value of the Economy set point
shift X
SBY
.
•
Dead Zone Span X
DZ
: The dead zone span lies between the heating and the cooling set point. The user can
change the heating or cooling set points within adjustable limits.
•
Switching Hysteresis: Defines the difference between switching on and switching off of an output. A small
hysteresis will increase the number of switching cycles and thus the wear on associated equipment.
•
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.
•
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. The fan will still switch off once the unit is set to OFF.
T Room
Temperature
w
H
Setpoint Heating Mode
D
Z
Dead
Zone
X
FH
Switching
Span
Heating
w
C
Setpoint Cooling Mode
X
FC
Switching
Span
Cooling
H
F
Hysteresis
Output Configuration
Two options are available: 3-point or binary.
3-point output
If 3-point is selected a 3-point actuator may be driven. The actuator has an open input and a close input. Applying
power to the Open input will drive the valve or damper open, applying power to the close input will drive the valve or
damper to the closed position.
The running time of the actuator may be preset. We recommend to enter the maximum running time under maximum
load in order to make sure that the valve can fully close and fully open in any circumstance.
In order to open the valve or damper DO4 will be activated for the preset amount of time. After the expiration of the
running time DO4 and DO5 will be OFF. The valve is closed by activating DO5 for the preset amount of time.
Binary output
Two devices may be controlled in case the 3-point actuator setting is OFF. DO4 will control a heating and DO5 a
cooling device.
Fan Medium
Fan Low
Fan High
Coil
X
FH
0
W
H
X
FC
W
C
Heating Mode
Cooling Mode
T [K]
H
F
Mold protection
ON
D
Z
