Honeywell R7426A Thermostat User Manual

Home
href="
HONEYWELL  
R7426A,B,C  
TEMPERATURE CONTROLLER  
MicroniK 200  
WITH AND WITHOUT REAL-TIME CLOCK  
INSTALLATION & START-UP INSTRUCTIONS  
GENERAL  
This document provides instructions and procedures for  
installing and starting up the Micronik 200 R7426A,B,C  
controllers. No special tools are required for mounting and  
installation. The user interface and liquid-crystal display allow  
accurate and easy parameter setting and output adjustment.  
BEFORE INSTALLATION NOTE  
•
Visually inspect equipment for shipping damage.  
Report any damage to the appropriate Honeywell  
representative.  
•
•
Refer to job drawings for specific installation  
information and mounting location.  
Verify the controllers will be adequately separated  
from the main power supply, relays, or other equip-  
ment which can possibly generate electromagnetic  
interference.  
Fig. 1. Temperature Controller  
•
Verify that the ambient temperature and the humidity  
at the controllers will not exceed 0...50°C (32...122°F)  
and 5 to 95% rh.  
Contents  
•
•
Use shielded wiring in areas with high EMI.  
All wiring should be separated from power lines by at  
least 150 mm (6’’).  
Do not install controllers near frequency converters  
or other high-frequency sources.  
General................................................................................ 1  
Before Installation Note ....................................................... 1  
Mounting.............................................................................. 1  
Wiring .................................................................................. 2  
Power Supply and Grounding.............................................. 2  
Configuration and Control Parameters ................................ 3  
Configuration Settings ......................................................... 6  
Parameter Settings and Adjustment .................................... 8  
Operating Overview............................................................11  
Notes (with RTC, only)....................................................... 19  
•
MOUNTING  
The controllers can be mounted in an electric cabinet or other  
suitable enclosure. They are suitable for back panel, DIN rail,  
wall, or front panel mounting. The corresponding mounting  
sequence, as well as dimensions and panel cut-out, are  
illustrated in the mounting instruction sheet EN1B-0202GE51  
supplied with the controllers.  
If the compensation sensor signal (T3) is received from  
another controller (parallel connection of compensation  
sensor inputs), the jumper W303 has to be cut before  
mounting the controller (see Fig. 2). This disconnects the  
sensor from the internal power supply.  
Copyright © 2007 Honeywell GmbH ꢀ All Rights Reserved  
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
WIRING  
Screwless type, spring loaded terminals are provided on  
the controllers for panel and field wiring. These terminals  
are suitable for solid conductors as well as tinned or with  
2
multicore cable end, stranded wires up to 1.5 mm . To  
make a termination, push the wire into the terminal or insert  
a small screwdriver from the front of the controller into the  
spring-release hole and insert the wire. Check for proper  
W303  
connection by short pull on the wire.  
Table 1. Terminal Connection  
controller to CPA/SPA potentiometer  
Fig. 2. Parallel Connection of Compensation Sensor T3  
T7412B1057/1008 T7412B1024  
T7412C1030/1006 T7412B1040  
R7426A,B,C T7412B1016  
Table 3. Jumper States  
state description  
closed  
terminal 2  
terminal 4  
terminal 4  
terminal 5  
terminal 4  
terminal 4  
1
)
jumper  
W303  
terminal 6  
terminal 5+6  
T3 supplied by this controller  
R7426A,B,C 43193982-001  
-
-
-
-
-
-
T3 supplied from another  
controller  
open  
terminal 2  
terminal 4  
terminal 1  
terminal 3  
1
)
Default jumper position = closed. Cut (open) jumper W303  
only if the T3 input is fed from another controller (parallel  
connection, max. six devices). This disconnects the T3 input  
from the internal power supply  
Table 2. Wire Dimensions  
type of  
wires  
length max.  
2
wiring run  
2
1.0 mm  
1.5 mm  
Wiring should be done only according to the actual job  
wiring diagrams or wiring diagrams shown in the mounting  
instruction sheet EN1B-0202GE51. The wiring to the  
CPA/SPA potentiometers is described in Table 1. All wiring  
must conform to applicable codes, ordinances, and  
regulations. The maximum allowed wiring length per wire  
size are shown in Table 2.  
from controller to all  
input and output  
devices  
local  
standard  
100 m  
150 m  
POWER SUPPLY AND GROUNDING  
1
. Refer to job drawings and verify correct supply voltage to  
transformer (230 Vac) and controller (24 Vac).  
3. Connect transformers 24 Vac secondary to the controller  
terminals 18 and 19. Connect one conductor to terminal  
marked 24 V∼ and the other to terminal marked 24 V⊥. If  
controllers are interconnected all terminals 19 must be  
connected to the same potential 24 V⊥ level.  
2
. Connect line power conductors to transformer primary.  
Line power must be supplied from a breaker panel with  
dedicated controller circuit. Do not turn the line power on  
until all wiring has been checked against job drawings.  
4. Do not connect the secondary side of the transformer to  
the installation ground.  
EN1B-0203GE51 R0507C  
2
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
CONFIGURATION AND CONTROL PARAMETERS  
*
)
The controllers R7426A,B,C include two groups of settings (I and II) for control and configuration parameters that are  
automatically selected during programming. For parameter Ctrltyp = Lo, setting I is selected, and for parameter Ctrltyp =  
Hi1/Hi2, setting II is selected.  
config. par.  
no. name  
default  
setting  
R7426  
actual  
value  
description  
A
B
C
C.01 DIR/REVY1 Selects the output action of Y1 to adapt the valve or damper direction  
C.02 DIR/REVY3 Selects the output action of Y3 to adapt the valve or damper direction  
C.03 DIR/REVY2 Selects the output action of Y2 to adapt the valve or damper direction  
Dir  
Dir  
Dir  
x
x
x
Dir Direct acting output signal  
Rev Reverse acting output signal  
Control type selects the setpoint operating range and default parameter  
setting I or II.  
set- operating range  
pt.  
1
)
C.04 Ctrltyp  
Lo  
x
x
x
x
x
for I  
*)  
setting  
Lo 0...50°C  
Hi1 0...130°C  
Hi2 0...130°C  
for ventilation systems (factory preset)  
I
II  
II  
for heating systems  
with pump ON/OFF operation  
C.05 CPATYP  
Selects the Control Point /SetPoint Adjustment type.  
0
x
CPA potentio-  
CPA/SPA  
sensor / remote setpoint unit type  
numbers  
TYP meter range range  
0
1
internal  
953...1053Ω CPA: ±5K  
CPA: ±5K  
internal  
T7412B1016 (Pt 1000)  
T7412B1057 / T7412C1030 (Pt 1000)  
T7412B1008 / T7412C1006 (NTC 20kΩ)  
43193982-001  
2
100kΩ...0Ω CPA: ±5K  
SPA:  
T7412B1024 (BALCO 500)  
T7412B1040 (Pt 1000)  
3
10...20kΩ  
1
5 ... 30°C  
4
5
0...10kΩ  
0...100kΩ  
CPA: ±5K  
SPA: 15...30°C 43193982-001  
HCW 23 (setpt wheel printed with +/- 5 K)  
SPA: 0...50°C  
43193982-001  
or 0...130°C  
6
0...100kΩ  
C.06 YRange  
C.07 Startup  
Selects the output control range for all outputs (Y1, Y2, and Y3)  
1
x
x
0
1
2 ... 10 Vdc  
0 ... 10 Vdc  
Enables the start-up routine  
OFF  
x
OFF Disabled  
ON Enabled  
C.08 Y1Mode  
C.09 Y3Mode  
C.10 Y2Mode  
Y1 output mode selects an individual output function for Y1  
Y3 output mode selects an individual output function for Y3  
Y2 output mode selects an individual output function for Y2  
4
4
4
x
x
x
x
0
1
2
3
4
Synchronous / floating  
2 stage ON/OFF  
3 stage binary coded ON/OFF  
Pulse-width modulation  
Unconfigured  
C.11 YMode  
Selects the output mode for sequence operation or multistage ON/OFF func.  
0
0
Damper, cooling and heating (Y1,Y2, Y3)  
Sequence control for heating or cooling (Y1,Y2, Y3);  
or 6-stage ON/OFF  
x
x
x
x
x
1
Sequence control for heating (Y1, Y3) and cooling (Y2);  
or 4-stage ON/OFF for heating (Y1, Y3), and cooling (Y2)  
Sequence control for cooling (Y1, Y3) and heating (Y2);  
or 4-stage ON/OFF for cooling (Y1, Y3), and heating (Y2)  
Two-position damper control (Y1), heating (Y3) and cooling (Y2)  
15-stage binary coded ON/OFF for heating (Y1, Y3), and cooling (Y2)  
x
x
x
x
x
x
x
x
x
2
3
4
5
Table 4. Configuration parameters R7426A,B,C  
3
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
config. par.  
default  
setting  
I / II  
R7426  
actual  
value  
description  
no.  
name  
A
B
C
0
x
x
x
x
x
x
x
C.12 T2ext  
Enable / Disables the T1 sensor input to be used for both T1 and T2 inputs.  
0
1
T2 installed  
T1 signal used for T2  
x
x
C.13 LimTyp  
C.14 Senstyp  
Limitation type determines whether the limit function is low or high.  
0 / 1  
0
0
1
Low limit  
High limit  
Sensor type determines automatic detection or manual selection of NTC  
sensors.  
0
1
Auto detection  
NTC sensor type  
0
/ 1  
x
x
x
C.15 Y1CTRF  
Controls the action of Y1 or activates the occupancy input for summer/winter  
changeover.  
R7426A  
R7426B,C  
0
1
2
cooling  
0
1
mixed air damper  
energy recovery  
heating  
summer/winter changeover  
2
)
3
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
C.16 AddHour Adjusts the month for winter/summer time change.  
Min. 0 (disables winter/summer time change)  
Max. 12  
(March)  
2
)
10  
C.17 SubHour Adjusts the month for summer/winter time change.  
Min. 0 (disables summer/winter time change)  
Max. 12  
(Oct.)  
2
2
) 3)  
) 3)  
0
K/min  
K/min  
5 min  
C.18 PSTG_H  
C.19 PSTG_C  
Determines the prestart gradient to reach the comfort setpoint for heating.  
Min. 0 (disabled)  
Max. 2  
0
Determines the prestart gradient to reach the comfort setpoint for cooling.  
Min. 0 (disabled)  
Max. 2  
2
)
1
C.20 tvd  
Determines the damper prestart time before scheduled comfort mode  
Min. 0 (normal control)  
Max. 90  
2
)
5
0%  
x
x
x
C.21 Adapt  
Optimum Start Self Adaption speed  
Min. 0  
Max. 100  
1
)
254  
C.22 Adr  
Sets the serial communication address, used for service or maintenance.  
Min. 0  
Max. 255  
0
C.23 DefProg  
Initiates the default programming.  
0
1
No Default programming  
Initiates Default programming  
1
)
)
)
actual value will not be changed during reset to default parameter  
on Controllers with Real-Time Clock, only  
2
3
can be overwritten by controller for self-adaption purposes, resolution = 0.01 K/min  
For detailed information of configuration parameters see chapter Configuration Settings.  
Table 4. Configuration parameters R7426A,B,C (part 2)  
EN1B-0203GE51 R0507C  
4
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
control par.  
no. name  
setting I / setting II  
R7426  
reso-  
lution  
actual  
value  
description  
unit  
low  
high def.  
A
B
C
5
1
0 / 21 /  
30 70  
P.01 W1  
Main setpoint for input T1  
0
0.5  
1
°C  
°C  
x
x
x
x
x
5
3
/
0
50 / 16 /  
130  
P.02 Wlim  
Limit setpoint (low or high) for input T2  
x
90  
20  
0
P.03 Wcomp  
P.04 Wi  
Compensation changeover point for input T3  
Winter compensation authority  
-5  
-350  
-100  
OFF, 0  
0
40  
1
2
°C  
%
%
°C  
K
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
+350  
+100  
50  
P.05 Su  
Summer compensation authority  
Submaster or cascade setpoint  
0
1
P.06 Wcas  
P.07 Rcas  
P.08 Xp1  
20  
10  
2
0.5  
0.5  
0.5  
Cascade reset span adjustment  
40  
Throttling range (main control loop) for T1  
0.5  
40  
K
Throttling range (cascade or limit control loop)  
for T2  
P.09 Xp2  
0.5  
40  
10  
0.5  
K
x
x
x
P.10 Xpc  
P.11 Xph  
Cooling throttling range for sequence control  
Heating throttling range for sequence control  
OFF, 1  
1
40  
40  
3
6
0.5  
0.5  
K
K
x
x
x
x
1
)
OFF,  
20  
min  
10/  
0.5  
sec/  
min  
P.12 tr1  
P.13 tr2  
Reset time (main control loop)  
OFF  
OFF  
x
x
x
x
x
x
20 sec  
1
)
OFF,  
20  
min  
10/  
0.5  
sec/  
min  
Reset time (cascade control loop)  
20 sec  
P.14 MINPOS  
P.15 Ystart  
P.16 SOFFS  
P.17 T1Cal  
P.18 T2Cal  
P.19 T3Cal  
P.20 RetOffs  
Minimal pos. for air damper actuators  
Start point for mid range shift of output Y1  
Offset of main setpoint in Standby mode  
Calibration of temperature sensor T1  
Calibration of temperature sensor T2  
Calibration of temperature sensor T3  
Return air offset to simulate exhaust air cond.  
0
-20  
0
50  
+20  
10  
20  
0
1
%
K
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
0.5  
0.1  
0.1  
0.1  
0.1  
x
x
x
x
x
2
K
-20  
-20  
-20  
OFF, 0  
6
+20  
+20  
+20  
5
0
K
0
K
0
K
OFF 0.1  
K
P.21 RuntimeY1 Actuator run time for Y1  
P.22 RuntimeY3 Actuator run time for Y3  
P.23 RuntimeY2 Actuator run time for Y2  
180  
180  
180  
19  
60  
60  
1
1
sec  
sec  
sec  
°C  
°C  
K
x
6
6
60  
1
2
)
P.24 NightLow Night low limit against temperature extremes  
OFF, 8  
OFF  
OFF  
5
1
x
x
x
x
x
x
2
)
P.25 NightHigh Night high limit against temperature extremes OFF, 21  
40  
1
2
)
P.26 NOFFS  
Offset of main setpoint in Night mode  
0
30  
0.1  
1
)
for tr > 2 min ⇒ resolution = 0.5 min, for tr < 2 min ⇒ resolution = 10 sec  
2
)
on Controllers with Real-Time Clock, only  
For detailed information of control parameters see chapter Parameter Settings and Adjustment.  
Table 5. Control parameters R7426A,B,C  
5
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
CONFIGURATION SETTINGS  
The controllers R7426A,B are supplied with unconfigured  
outputs to avoid damage of installed final control devices by  
supply of not applicable output signals if the controller power  
supply is turned on.  
Table 6. Selection of CPA/SPA Type  
CPA / SPA  
range  
sensor /  
remote setpoint unit type  
CPATYP  
CPATYP 0  
CPA: ±5 K  
internal  
All configuration parameters must be set to select the correct  
control functions as required for the job application and to  
start control operation and synchronization of the final control  
devices.  
CPATYP 1  
CPA: ±5 K  
T7412B1016 (Pt 1000)  
(953...1053Ω)  
T7412B1057 (Pt 1000)  
T7412C1030 (Pt 1000)  
T7412B1008 (NTC 20kΩ)  
T7412C1006 (NTC 20kΩ)  
43193982-001  
CPATYP 2  
CPA: ±5 K  
Direct - Reverse Action  
Dir/Revx, x = Y1, Y2 or Y3 (C.01...C.03)  
(100kΩ...0Ω)  
The output action of the analog outputs on the R7426C  
controller must sometimes be reversed for a correct opening  
and closed direction of the valve or damper. This depends on  
whether the output controls a 2-way or 3-way valve or on the  
direction the damper shaft moves to open the damper (cw or  
ccw). It is needed only if the actuator does not provide a  
direction selector switch, plug, or similar.  
CPATYP 3  
(
SPA:  
15 ... 30°C  
T7412B1024 (BALCO 500)  
T7412B1040 (Pt 1000)  
10...20kΩ)  
CPATYP 4  
0...10kΩ)  
HCW 23 (setpoint wheel  
printed with +/- 5 K)  
CPA: ±5 K  
(
CPATYP 5  
SPA:  
15...30°C  
4
3193982-001  
3193982-001  
(0...100kΩ)  
In the case of the R7426A,B controllers, the direction can be  
changed by exchanging the wiring connections open-close  
CPATYP 6  
SPA: 0...50°C  
or 0...130°C  
4
(0...100kΩ)  
(
OUT2-OUT1).  
Output Control Range Selection  
Operating Range Selection Ctrltyp (C.04)  
YRange (C.06)  
The controllers provide two operating ranges which can be  
The configuration parameter YRange is available only on the  
R7426C controller and is required to select the output control  
range (0...100%) to either 2...10 Vdc (YRange = 0) or  
selected by the configuration parameter Ctrltyp  
(Lo = 0...50°C, Hi1/Hi2 = 0...130°C).  
Depending on this parameter setting, the setpoint ranges for  
the main temperature (W1), limit temperature (Wlim), and  
submaster temperature (Wcas) are selected for air tem-  
perature applications (Ctrltyp = Lo) or for flow water  
temperature applications (Ctrltyp = Hi1/Hi2).  
0
...10 Vdc (YRange = 1). The selected control range is  
common to all outputs.  
Enabling the Start-up Routine (C.07)  
A start-up routine is provided to prevent start-up problems for  
the R7426B,C controllers (three outputs). This routine can be  
enabled by setting the configuration parameter Startup to  
ON.  
If the configuration parameter Ctrltyp = Hi1, normal operation  
for flow water application will be performed. If Ctrltyp = Hi2,  
the following additional function will be active on controllers  
with real-time clock:  
The controller switches the ON/OFF output (e.g. the pump)  
from ON to OFF if  
Individual Output Function Selection  
-
-
the outside air temperature is above 8°C and  
the output signal Y1 = 0% for more than 5 minutes during  
the controller is in the Comfort, Standby, or Night mode.  
YxMode, x = 1, 2, or 3 (C.08...C.10)  
The R7426A,B controllers provide a choice of output signals  
suitable for operating a range of final control devices  
according to the configuration parameter Y1Mode (for  
R7426A,B) and Y2Mode, Y3Mode (for R7426B, only).  
Changing the configuration parameter Ctrltyp value from Hi-  
to Lo control range or vice versa causes the controller to  
change all parameter values to default, depending on the  
selected Ctrltyp value.  
Each output can be configured individually by this con-  
figuration parameter (see Table 7).  
For a direct parameter reset by the user, refer to chapter How  
to reset Parameter Values to Default Values? on page 12.  
Table 7. Individual Output Function Selection  
YxMode  
output function  
(x = 1, 2 or 3)  
Control Point / Setpoint Adjustment CPATYP  
Valve or damper actuators (floating mode)  
0
1
2
3
4
2-stage ON/OFF Sequence Control  
(
C.05)  
3-stage Binary ON/OFF Sequence Control  
The control point or setpoint can be adjusted via the internal  
or external potentiometer connected to the CPA/SPA input.  
The potentiometer type is selected by the configuration  
parameter CPATYP (see Table 6).  
Electric Heat Current Valve (pwm output)  
unconfigured  
EN1B-0203GE51 R0507C  
6
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL TIME CLOCK  
Output Signal Mode YMode (C.11)  
Supply of Temperature Signal T2  
T2ext (C.12)  
Sequence Operation  
The controllers R7426B,C are supplied from the factory  
configured for sequence operation of heating, mixed air, and  
cooling control.  
If sensor T1 is used also for high or low limit control, the con-  
figuration parameter T2ext must be set to 1. This inter-  
connects the T1 and T2 input internally and the sensor has to  
be connected only to the T1 input.  
The sequence operation can be configured for the following  
control applications by the control parameters YMode and  
Y1CTRF (see Table 8). Sequence control will be activated if  
at least one control parameter YxMode is not equal 4  
By using a limit temperate sensor T2, the parameter T2ext  
has to be set to 0 (default).  
(
R7426B, only).  
Limit Type LimTyp (C.13)  
Table 8. Sequence Operation Selection  
The configuration parameter LimTyp allows the selection of  
high or low limit control. High limit control is performed if  
configuration parameter LimTyp = 1; low limit control is  
performed if configuration parameter LimTyp = 0.  
sequence control  
YMode Y1CTRF YxMode  
for cooling with three outputs  
1
1
0
1
0
0
(
Y1, Y2, Y3)  
for heating with three outputs  
Y1, Y2, Y3)  
(
Sensor Type Senstyp (C.14)  
with two outputs (Y1, Y3) for  
heating and one output for  
cooling (Y2)  
Three different sensor types can be used with the controller  
2
3
n.a.  
n.a.  
0
0
(see Table 10).  
Table 10. Sensor Types  
temperature  
with one output (Y2) for  
heating and two outputs for  
cooling (Y1, Y3)  
automatic ID  
characteristics  
of sensor type  
range  
damper, cooling and heating  
Pt 1000  
-30....+130°C  
-30....+130°C  
-30....+85°C /  
1000Ω at 0°C  
500Ω at 23.3°C  
0
0
0
1
0
0
(Y1, Y2 and Y3)  
BALCO 500  
energy recovery, cooling and  
heating  
NTC 20kΩ  
1)  
30....+130°C  
20kΩ at 25°C  
-
1) NTC sensor is detected automatically if, during power-  
up, the sensor temperature is within -30....+85°C and the  
configuration parameter Senstyp = 0. NTC sensor is  
selected manually if the configuration parameter Senstyp  
is set to 1.  
Multistage ON/OFF Function  
In the case of the three floating output controller R7426B,  
several ON/OFF sequence control functions can be selected  
by the configuration parameter YMode (see Table 9).  
Automatic identification of sensor type is selected if the  
configuration parameter Senstyp = 0 (default). After power up  
reset, the controller detects automatically the type of sensor  
connected to the main temperature input T1. For correct auto  
detection, it is necessary that the measured temperature be in  
the specified range (see Table 10). The same type of sensor  
must be used for all temperature inputs (T1, T2 and T3).  
Table 9. Multistage Selection  
provided  
function  
output function  
YMode YxMode  
by  
of Y2  
output  
6
-stage ON/OFF  
sequence control  
4 (x=1, 2,  
and 3)  
1
Y1,Y2,Y3 n.a.  
Y1,Y3  
4
-stage ON/OFF  
sequence control  
heating  
4
(x=1  
2
3
and 3)  
Output Control Function Y1CTRF (C.15)  
The R7426A controller performs cooling control if the  
configuration parameter Y1CTRF is set to 0. A rise in the  
measured variable will increase the output value (direct  
acting). The control action must be reversed for heating  
control by setting the control parameter Y1CTRF to 1. A rise  
in the measured variable will decrease the output value.  
4
-stage ON/OFF  
sequence control  
cooling  
4
(x=1  
according  
Y1,Y3  
and 3)  
to  
Y2Mode  
1
5-stage binary  
coded ON/OFF  
sequence control  
H.  
5
4
n.a.  
Y1,Y3  
Y1  
If the configuration parameter is set to 2, the R7426A  
controller provides summer/winter changeover control by a  
potential-free contact connected to the occupancy input  
two-position  
Y2 and  
n.a.  
1)  
damper control  
Y3  
(terminals 1 and 4).  
1
)
individual (cooling and heating)  
In the case of the R7426B,C controller, the configuration  
parameter Y1CTRF has to be set to 0 (default) to perform  
mixed air damper control and to 1 for energy recovery  
systems.  
In the case of the R7426B,C controller, the output Y1 can be  
configured for two-position damper control by setting the  
configuration parameter YMode to 4.  
7
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL TIME CLOCK  
Summer / Winter Time Change  
AddHour / SubHour (C.16 / C.17)  
Default Programming DefProg (C.23)  
Setting the control parameter DefProg to 1 resets all control  
and configuration parameters to defaults (see Table 4 and  
Table 5). Default programming is indicated by a display of def.  
These configuration parameters are only available on  
controllers with RTC. The configuration parameter AddHour  
or SubHour are required to adjust the month for  
summer/winter time change or vice versa.  
After default programming, the parameter DefProg is reset to  
0.  
The actual clock is incremented by one hour at 2:00 on the  
last sunday of the month for winter/summer time change  
PARAMETER SETTINGS AND  
ADJUSTMENT  
(
2
AddHour). The actual clock is decremented by one hour at  
:00 on the last sunday of the month for summer/ winter time  
change (SubHour).  
Main Setpoint W1 (P.01)  
The main setpoint is either set by the control parameter W1 or  
by the external setpoint potentiometer if the configuration  
parameter CPATYP = 3, 5 or 6.  
Prestart Gradients PSTG_H / PSTG_C  
(C.18 / C.19)  
The configuration parameter PSTG_H or PSTG_C are  
necessary for the optimum start program on controllers with  
RTC. For heating and cooling applications, these parameters  
determine the prestart gradient to reach the comfort setpoint  
at occupancy start.  
High/Low Limit Setpoint Wlim (P.02)  
For high or low limit control, the control parameter Wlim is  
used as setpoint.  
During limit control, the throttling range Xp2 and reset time  
tr2 are active.  
If the comfort setpoint will be reached earlier or later than  
expected, the controller corrects the prestart gradient by self-  
adaption routine to optimize the start cycle.  
Limit control will be active only if the T2 temperature signal  
(control parameter T2ext = 0) is available or alternatively the  
The optimum start cycle for heating or cooling can be  
disabled by setting PSTG_H or PSTG_C to 0.  
sensor T1 (control parameter T2ext = 1) is used also for limit  
control.  
For cascade control, the limit setpoint Wlim determines the  
control point at which the submaster setpoint (Wcas) maintains  
the limit value and is not shifted anymore by the master  
control loop.  
Optimum Start Self Adaption Speed  
Adapt (C.21: Controller with RTC only)  
This parameter is used by the self-adaption routine to  
optimize the energy consumption during the start cycle. For  
this optimization, a corrected prestart gradient is calculated  
once per day. The adaption to the actual prestart gradient for  
the next optimum start cycle is determined by the self  
adaption speed Adapt (0% = adaption disabled and 100% =  
max. adaption speed).  
High or low limit control is in accordance with the con-  
figuration parameter LimTyp (C.13).  
Submaster Setpoint W (P.06)  
cas  
The R7426A,B,C controllers provide cascade control which  
uses two control loops, master and submaster to maintain the  
master setpoint CTRP1. Cascade control will be active if  
temperature sensor T2 is connected and the control para-  
meter Wcas is set to any value other than OFF.  
Damper Prestart Time tvd  
This adjustment sets the control point of the submaster  
control loop, discharge temperature (T2), at zero room  
temperature deviation. If the room temperature deviates, the  
submaster setpoint Wcas is automatically altered.  
(
C.20: Controller with RTC only)  
The damper prestart time tvd is active with the optimum start  
program only and is used to set the time before occupancy  
start (scheduled comfort mode) at which the output signal Y1  
Cascade control is disabled if the submaster setpoint Wcas is  
set to OFF.  
(damper) switches to normal operation to supply fresh air to  
the space in mixed air applications.  
Low limit of CTRP2 is performed if control parameter  
LimTyp = 0 and high limit of CTRP2 is performed if control  
parameter LimTyp = 1.  
Serial Communication Address Adr (C.22)  
The configuration parameter Adr sets the serial  
communication address.  
The serial communication bus allows the connection of the  
PC-based Operator’s Terminal to one or several controllers. It  
provides access to all application configuration and control  
parameters, time schedules, input and output values of the  
connected controllers and easy setting of these via the bus by  
mouse click or keyboard.  
Reset Span Adjustment R (P.07)  
cas  
The reset span adjustment Rcas determines the reset effect in  
Kelvin. The submaster setpoint Wcas is altered if the tem-  
perature (T1) deviates by 50% of the throttling range Xp1.  
Throttling Range Xp1 / Xp2 (P.08 / P09)  
p
Proportional band (throttling range X ) adjustment determines  
the temperature change, required at the main sensor (T1) and  
EN1B-0203GE51 R0507C  
8
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL TIME CLOCK  
limit or cascade sensor (T2) to operate the output device from  
full open (100%) to full closed (0%) or vice versa.  
Setting Guidelines for Proportional Band of P and  
P+I Control  
Xp1 is the throttling range for the main control loop, Xp2 is  
used if limitation or cascade control (submaster control loop)  
is active (see Table 11).  
p
To estimate the proportional band (throttling range X ) for  
stable control under all different load conditions, the control or  
correcting range X of the heating or cooling coil must be  
h
known. This is the maximum air temperature increase pro-  
duced by the heating coil or decrease of a cooling coil if the  
control valve is fully open.  
Table 11. Throttling range and reset time reference  
application  
R7426A Controller  
Main Temp.Control  
sens. Xp1 Xp2 Xpc Xph tr1 tr2  
The proportional band X for discharge air control can be  
p
T1  
T2  
x
x
x
x
calculated by using the following rule-of thumb formula:  
High or Low Limit  
Temperature Control  
X
Xp =  
5
h
x
x
x
x
Cascade Control  
Master  
For room temperature control, the following rule-of-thumb  
formula can be used:  
T1  
T2  
Submaster  
X
h ∆tmaxdischarge air  
or  
10  
Xp  
=
R7426B,C Controller  
Main Temp. Seq. Control  
Mixed Air Damper  
Energy Recovery  
Heating  
10  
h
The ∆tmax (X ) of the discharge air for mixed air damper con-  
trol is the maximum difference between outdoor air (OA)  
temperature and return air (RA) temperature.  
T1  
T1  
T1  
T1  
x
x
x
x
x
x
X = ϑ - ϑOAmin  
h
RA  
x
The often-specified accuracy for room control of ±1 (X = 2K)  
p
Cooling  
x
allows a discharge air alteration of 20 °C.  
R7426B,C Controller  
In P+I control the same proportional band can be used as for  
P control. The following rule-of-thumb formulae are used for  
P+I control:  
Temperature Cascade  
Sequence Control  
Master  
T1  
x
x
X
Xp =  
4...5  
∆tmaxdischarge air  
h
•
Discharge air control  
Submaster  
-
-
-
-
Mixed Air Dampers  
Energy Recovery  
Heating  
T2  
T2  
T2  
T2  
x
x
x
x
x
x
X
h
•
Room control  
Xp  
=
or  
8
...10  
8 ... 10  
x
Cooling  
x
Reset Time tr1 / tr2 (P.12 / P13)  
X
w
Throttling Range Xpc / Xph (P.10 / P11)  
The control parameters Xpc and Xph are only available on  
R7426B,C controllers and are used to set the cooling and  
heating throttling ranges for the following applications  
0
t
•
Temperature sequence control with heating, mixed air  
dampers, and cooling (see Fig. 3 and Table 11)  
Y
•
Temperature cascade control with heating, mixed air  
dampers, and cooling (see Table 11)  
P
tr  
%
/s  
P
In applications without cooling, the throttling range Xpc must  
be set to OFF 100% fresh air supply at actual temperature  
above the control point is required (outdoor and return air  
dampers fully open).  
1
00  
X
%
w
P =  
X
p
t
Y[%]  
tr  
1
/4 Xp1  
if Xpc = Off  
100  
Fig. 4. Step change response of P+I control  
Damper  
Y1  
Y3  
Heating  
Y2  
In the case of combined action including proportional and  
integral components (P+I control), the reset time (tr) is  
defined as the required time after which the integral part is  
equal to the change due to the proportional action for a  
predetermined step change in the input variable. See Fig. 4.  
The control parameter tr1 sets the reset time of the P+I main  
temperature control loop. For limit or submaster cascade  
control the control parameter tr2 sets the reset time of these  
control loops, e.g. discharge temperature T2 (see Table 11).  
Cooling  
MINPOS  
0
if Xpc = Off  
Xwh/Xwc/Xwd  
CTRPH CTRP1 CTRPC  
Xp1  
T2  
Xph  
Xpc  
Fig. 3. Temperature sequence control with heating, mixed  
air dampers, and cooling valve  
If only proportional control is required, parameter tr must be  
set to OFF.  
9
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL TIME CLOCK  
Table 12. Calculation of summer/winter compensation  
Setting Guidelines for Reset Time of P+I Control  
The reset time tr should be adjusted to 2...3 times of the  
outdoor air  
temp.  
control  
schedule  
room temp.  
(T1)  
throttling  
range (X )  
P
u
response time T , which is the time interval between the  
beginning of a sustained disturbance (e.g. rapid step change  
of valve position) and the instant when the resulting change in  
the output signal reaches a specified fraction of its final  
steady-state value, either before overshoot or in the absence  
of overshoot.  
(T3/Tcomp)  
20  
-15  
2
2
0
2
°
C
C
°C  
2
2
°
C
C
°
°C  
°
∆
T1  
⋅100% =  
t Outside Air  
+ Xp  
Aut Wi =  
∆
The response time T in discharge air control is normally in  
u
Winter  
(22 - 20)+ 2  
the range of 0.1 to 0.6 min, which allows adjustments of the  
reset time tr in a range of 0.2 to 2 min.  
⋅
100% =≈ 12%  
35  
In room control the response time T is in the range of  
20  
°
C
C
20  
35  
°
C
C
2
2
°
C
C
u
0.5 to 5 min, which results in a setting of 1 to 15 min.  
2
6
°
°
°
∆
T1− X  
t Outside Air  
26 - 20) - 2  
p
Aut Su =  
⋅100% =  
∆
Start Point Ystart (P.15)  
Summer  
(
This control parameter is available only on the single output  
controller R7426A and on the R7426B controller if the three 3-  
position floating outputs are configured for 6-stage ON/OFF  
sequence control and on the R7426B,C controllers if YMode  
⋅
100% =≈ 27%  
1
5
Compensation change-over at +20  
NOTE: With P+I control X = 0  
°C outdoor air temperature  
p
=
1 is selected.  
The start point determines the midrange shift of the output Y1  
from the calculated control point.  
Occupied/Unoccupied Function SOFFS  
P.16)  
The start point is calibrated in degrees K and is the offset  
(
(plus or minus) from the set values or calculated control  
A potential-free contact can be used between terminals 1 and  
to switch the controller between occupied (contact closed)  
points at which the output Y1 is at 50%. Normally and  
especially in P+l control, the start point should be set at zero.  
A change is required only in specific applications where a  
asymmetrical arrangement results in improved control per-  
formance, e.g. if for heat-up of a large space in the morning a  
high heat capacity is needed and for normal control the valve  
must be opened by only a small amount.  
4
or unoccupied (contact open) mode.  
In occupied mode, the temperature set point W1 is used for  
the control point calculation. In unoccupied mode, the SOFFS  
parameter value is added (cooling) to or subtracted (heating)  
from the calculated control point.  
In the case of the R7426A controller, the parameter Y1CTRF  
must be set to 0 or 1 (≠ Cho) to match the required heating or  
cooling application.  
Compensation Changeover Point Wcomp  
(
P.03)  
If the configuration parameter Y1CTRF is set to 2 (summer /  
winter changeover), the parameter SOFFS is not considered.  
The control parameter Wcomp defines the start point of  
summer or winter compensation. Above the compensation  
changeover point (Wcomp) summer compensation and below  
In sequence applications of heating and cooling, the SOFFS  
parameter value is added to the control point for cooling  
(CTRPC) and subtracted from the control point for heating  
W
comp winter compensation is performed.  
(
CTRPH) (see Fig. 5).  
Summer / Winter Compensation Authority  
Night Mode Offset NOFFS  
Su / Wi (P.04 / P.05)  
(
P.26: Controller with RTC only)  
These authority settings determine the reset effect (OATComp  
)
This control parameter is used to set the night mode offset.  
the compensation sensor (T3) has on the main setpoint W1 in  
percentages. Outside temperature reset in summer and  
winter time are commonly used applications.  
During night mode, freeze protection is active and the  
occupied / unoccupied function is inactive.  
To calculate winter and summer authority, the throttling range  
must be considered in proportional-only control according to  
Table 12.  
Night Cycle NightLow and NightHigh  
(
P.24 and P.25: with RTC, only)  
The control parameters NightLow and NightHigh are used  
by the night cycle program (controller mode = OFF) to assign  
unoccupied night low or high limits for the protection of a  
space and its contents against temperature extremes.  
EN1B-0203GE51 R0507C  
10  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL TIME CLOCK  
Y (%)  
00  
If the controller is in OFF mode, the time schedule program  
overrides the minimum position by the ON/OFF input for  
plant/system shut off and the damper is driven into the fully  
closed position at OFF condition together with the heating and  
1
UNOCCUPIED  
cooling valve actuators.  
OCCUPIED  
Runtimex, x = Y1, Y2, or Y3 (P.21...P.23)  
The control parameters Runtimex (x = Y1 for R7426A;  
x = Y1, Y2 or Y3 for R7426B) are available only on  
R7426A, B controllers.  
SOFFS  
Xph  
SOFFS  
Xpc  
The controller converts the deviation signal to a proportional  
output pulse which drives the actuators depending on the  
Runtimex parameter value.  
T (°C)  
An automatic synchronization function ensures correct  
positioning of the actuators. The run time for synchronization  
is derived by control parameter Runtimex multiplied by 1.25.  
CTRPH CTRPC  
Fig. 5. Night cycle NightLow and NightHigh  
By selection of the output to pwm mode, the pulse-width  
modulated output is suitable for driving electric heat current  
valves and is controlled from the heating signal. The total  
The night cycle program automatically cycles between the  
user selected upper and lower limits and turns on full heating  
or cooling with forced return air recirculation or full energy  
recovery whenever the limits are reached. The switching  
hysteresis is fixed to 1 K.  
cycle time is set by the control parameter Runtimex  
.
OPERATING OVERVIEW  
This function can be disabled for heating and/or cooling by  
setting NightLow and/or NightHigh to OFF.  
Display and Operation Elements  
The MicroniK 200 user interface is described in Fig. 6.  
Calibration of Temperature Sensors  
NOTE: Pushing the + or - button increments/decrements  
values or scrolls through the parameter list:  
pushing one time: single step  
T1CAL, T2CAL, or T3CAL (P.17...P.19)  
The controllers include a calibration setting and are factory  
calibrated. In case of an offset as a result of long wiring  
lengths the temperature sensor inputs (T1, T2, and T3) can  
•
•
•
pushing without release: automatically inc./dec. or scroll  
after 3 sec pushing without release: fast automatically  
increment/decrement or scroll  
be adjusted separately by the control parameters T1CAL  
T2CAL and T3CAL  
,
.
DISPLAY  
CONTROLLER MODE  
Return Air Offset RetOffs (P.20)  
FREEZE PROTECTION  
TIME*  
OFF NIGHT* STANDBY COMFORT  
The control parameter RetOffs is available only on R7426B,C  
controllers and is used to activate economizer mode (RetOffs  
Date Off  
≠
OFF) for mixed air damper (Y1CTRF = 0) or energy  
LOW BATTERY*  
°C % rh min sec K  
ENGINEERING UNITS  
recovery system control (Y1CTRF = 1).  
If the main temperature sensor (T1) is installed in the exhaust  
air, the control parameter RetOffs should be set to 0. In  
applications with the main sensor installed in the room and  
with a constant offset between room and exhaust air  
conditions, this offset value can be adjusted within 0...5 K by  
the control parameter RetOffs. This will be added to the  
actual measured room temperature value to simulate exhaust  
air conditions.  
VALUE  
MoTuWeTh Fr SaSu H1H2 H3  
WEEKDAYS / GROUPS* HOLIDAY SCHEDULE TYPES*  
*
ON CONTROLLERS WITH REAL-TIME CLOCKS, ONLY.  
PUSH BUTTONS  
The economizer mode is disabled if the value of the control  
parameter RetOffs is programmed to OFF or if no outdoor air  
temperature sensor is connected.  
SELECTION OR ESCAPE  
ADJUSTMENT OR SELECTION  
PARAMETER / VALUE  
CONFIRMATION  
Minimum Position MINPOS (P.14)  
Fig. 6. User interface  
The control parameter adjustment MINPOS is available on  
R7426B,C controllers only and determines the minimum open  
position to which an outdoor air damper actuator can be  
driven from the controller. In mixed air damper applications it  
maintains the minimum outdoor air damper setting, even  
though the temperature input condition calls for a fully closed  
position.  
1
1
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL TIME CLOCK  
Changing Operating Modes  
Fig. 7 shows the six operating modes. After power-up the  
controller version is displayed and the controller enters the  
standard display mode. In this mode, selected input or output  
values and on controllers with real-time clock the time or the  
date are displayed. The controller mode is permanently  
displayed by a corresponding icon (Fig. 6).  
Pushing the SET and SEL button simultaneously for approx.  
1 sec causes the controller to leave the standard display  
mode and to enter the output data selection mode (Fig. 11).  
Pushing the SET button causes the controller to accept the  
selected output data no. and to enter the output adjustment  
mode (Fig. 12). This mode is used for manual override of  
output values. The return to standard display mode is shown  
in Fig. 7.  
Pushing the + and - button simultaneously for approximately  
sec causes the controller to leave the standard display  
1
mode and to enter the parameter/configuration selection  
mode (Fig. 9). This mode is used for application configuration  
and to select parameters for adjustment.  
Pushing the SET and - button simultaneously for approx.  
sec causes the controller to leave the standard display  
mode and to enter the clock / schedule selection mode (Fig.  
13) on controllers with real-time clock, only.  
1
Pushing the SET button causes the controller to accept the  
selected parameter or configuration no. and to enter the ad-  
justment mode (Fig. 10), which is used to adjust configuration  
/
parameter values. After adjustment, the controller returns to  
selection mode by pushing the SET or SEL button. Pushing  
the SEL button leads back to standard display mode.  
POWER UP  
AUTOMATIC  
DISPLAY  
FOR APPROX.  
AND  
1 SEC  
AND  
FOR APPROX.  
1
SEC  
OUTPUT  
ADJUSTMENT  
MODE  
OUTPUT  
SELECTION  
MODE  
STANDARD  
DISPLAY  
MODE  
PARAM./CONFIG.  
SELECTION  
MODE  
PARAM./CONFIG.  
ADJUSTMENT  
MODE  
OUTPUT  
FIXING  
NO PARAMETER  
VALUE CHANGE  
NO OUTPUT FIXING  
AND  
RELEASE OF  
OUTPUT FIXING  
FOR APPROX.  
1 SEC  
CLOCK /  
SCHEDULE  
SELECTION  
CONTROLLERS WITH  
REAL-TIME  
CLOCKS, ONLY.  
Fig. 7. Operating overview  
EN1B-0203GE51 R0507C  
12  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
Time Out  
After approximately 10 min of inactivity (no button has been  
pressed: time out), each mode returns automatically to  
standard display mode. Inputs that have not been confirmed  
by the SET button are ignored by the controller and old  
parameter values will be retained.  
A
B
A
°
C
TIME &  
WEEKDAY  
SUBMASTER / LIMIT SETPOINT  
CTRP2  
We  
ON CONTROLLERS  
WITH REAL-TIME  
CLOCK, ONLY  
Date  
°
C
COMPENSATION  
DATE  
TEMPERATURE T3  
We  
°C  
°C  
°C  
% rh  
MAIN  
TEMPERATURE T1  
HUMIDITY  
DEVIATION XWrh  
R7426B,C, ONLY  
%
MAIN SETPOINT  
CTRP1  
OUTPUT Y1 *)  
OUTPUT Y2 *)  
OUTPUT Y3 *)  
%
LIMITATION / CASCADE  
TEMPERATURE T2  
R7426B,C, ONLY  
%
B
*
) THE OUTPUT DATAS (Y1, Y2, AND Y3) ARE  
DISPLAYED BETWEEN THE FOLLOWING RANGES:  
OUTPUT TYPE  
FLOATING  
CONTROL RANGE  
0...100%  
OUTPUT RANGE  
0...100%  
...120% --> 0...12V (DIR)  
20...100% --> 12...0V (REV)  
-25...125% --> 0...12V  
A
0
0
2
...10VDC  
...10VDC  
0...100%  
0...100%  
*) DURING THE AUTOMATIC SYNCHRONIZATION FOR A CORRECT  
POSITIONING OF THE ACTUATORS, Syn IS DISPLAYED TOGETHER  
WITH THE CORRESPONDING OUTPUT NUMBER.  
-
Fig. 8. Standard display mode  
1
3
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
Displaying Actual Values  
°
C
In the standard display mode, one of nine actual values, the  
actual time, or the date can be selected and displayed by  
pushing the SEL button.  
The icons of the permanently displayed controller mode are  
described in the following table:  
°
C
Table 13. Icons  
controller mode / status  
display  
Off  
OFF - icon  
FIRST DISPLAYED CONFIGURATION  
PARAMETER:  
1
)
ACTUAL  
PARAMETER  
VALUE  
Night  
Moon - icon  
FOR R7426C  
Standby  
Comfort  
Halfsun - icon  
Sun - icon  
FOR R7426A,B  
Freeze Protection Alarm and Freeze protection icon in  
2
)
Operation  
Low battery  
Optimum Start  
addition  
1
) 2) 3)  
Battery icon  
1
)
Sun icon is flashing ≈ 1Hz  
1
)
On controllers with real-time clock, only.  
NOTE: CONTROL OR CONFIGURATION  
PARAMETERS WHICH ARE NOT  
AVAILABLE ON THE GIVEN  
CONTROLLER VERSION ARE  
SKIPPED.  
2
)
Status information is displayed together with actual icon  
for the controller mode.  
3
)
In order to improve battery lifetime, low battery detection  
is performed only once a day and after power up.  
Fig. 9. Parameter/Configuration Selection Mode  
If a displayed date is programmed to be a holiday, the  
corresponding holiday icon is displayed on controllers with  
real-time clock.  
TO ADJUST  
PARAMETER  
VALUE  
°C  
Selecting Parameters  
OR  
The parameter/configuration selection mode is used to select  
control and configuration parameters (Fig. 9) for adjustment.  
The displayed parameter no. corresponds with the number in  
Table 4 and Table 5. Default programming is indicated by a  
display of def.  
Fig. 10. Parameter/Configuration Adjustment Mode  
Pushing the  
+ or - button scrolls through the parameter list.  
Pushing the SET button enters the adjustment mode.  
Selecting Output Values  
The output selection mode is used to select the output no.  
(see Fig. 11) for manual override adjustment. An activated  
manual override is indicated by a displayed F (fixed).  
Adjusting Configuration / Parameter Values  
The adjustment mode is used to adjust configuration and  
parameter values (Fig. 10). In this mode, the selected para-  
meter no. is displayed and the corresponding value flashes.  
Pushing the  
+ or - button scrolls through the output list.  
Pushing the SET button enters the adjustment mode.  
Pushing the  
+ or - button increments or decrements the value  
of the selected parameter. Ranges are shown in Table 4 and  
Table 5. An adjustment example is shown in Fig. 18.  
Manually Overriding Output Values  
The output adjustment mode is used for manual override  
adjustment of output values (see Fig. 12). In this mode, the  
selected output no. is displayed and the actual output value  
flashes.  
Pushing the SEL button retains the old parameter value.  
Pushing the SET button accepts the parameter value and  
returns to parameter/configuration selection mode.  
Pushing the  
+ or - button increments or decrements the value  
Resetting Param. Values to Default Values  
+ and - button during the power  
of the selected output for manual override purpose. The  
output range is displayed in correspondence with the nominal  
control range.  
Pushing simultaneously the  
up or setting the control parameter DefProg to 1 resets all  
control and configuration parameters to defaults (see Table 4  
and Table 5). Default programming is indicated by a display of  
def.  
To return to output selection mode, three options are  
available:  
•
Pushing the SET-button after adjustment activates the  
manual override (fixing) of output value.  
•
Pushing the SEL button, causes that the output value is  
still determined by the control loop (no fixing).  
EN1B-0203GE51 R0507C  
14  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
•
To release the manual override (fixed) of the output, select  
the output, enter output adjustment mode and push the  
and button simultaneously.  
Pushing the SEL button leads back to standard display mode.  
+
-
WITH  
:
MANUAL OVERRIDE  
IS ACTIVE  
%
%
%
R7426B  
AND  
R7426C,  
ONLY  
WITHOUT  
:
CONTROL LOOP  
IS ACTIVE  
Fig. 11. Output Selection Mode  
%
%
OUTPUT  
SELECTION  
OUTPUT  
SELECTION  
%
%
TO ADJUST  
OUTPUT  
VALUE  
OUTPUT  
VALUE  
ADJUSTMENT  
OUTPUT  
VALUE  
ADJUSTMENT  
OR  
AND  
%
AUTOMATIC  
DISPLAY  
FOR APPROX.  
1
SEC  
%
%
%
OUTPUT  
SELECTION  
RELEASE OF  
MANUAL OVERRIDE  
MANUAL OVERRIDE  
NO MANUAL OVERRIDE  
Fig. 12. Output value adjustment for manual override  
1
5
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
Using the Schedules (with RTC, only)  
Two schedules, one for programming the schedule points and  
one for holiday programming, are available.  
a normal day (day type = H0 is default). The function is  
described as follows:  
The standard schedule is used to switch the controller mode  
•
•
H0: no holiday - the weekday schedule applies  
H1: free programmable as for a weekday, but only valid for  
the current day.  
H2: as H1 function - free programmable, additional holiday  
type, e.g. last or first day after a longer holiday period.  
NOTE: After day is passed, day type (H1 or H2) is reset at  
24:00 to normal.  
H3: free programmable as for a weekday, but is valid  
every year and repeated annually.  
(off, night, standby or comfort) at programmed schedule  
points (S1 ... S6), which can be set for each weekday or  
weekday group as well as for several holiday types (H1, H2  
and H3).  
•
If the comfort or standby mode is taken from the schedule and  
if the occupancy switch is connected, the controller mode is  
determined by the occupancy input as follows:  
•
•
Occupied (contact closed):  
Controller mode = Comfort (sun - icon)  
The schedule points of the used holiday types (H1, H2 or H3)  
must be programmed in the standard schedule. Table 15  
shows a programmed example of the holiday schedule (2.7.  
till 28.7. = holiday type H1 and 1.5. = holiday type H3).  
•
Unoccupied (contact open):  
Controller mode = Standby (halfsun - icon)  
The OFF and night controller modes are not influenced by the  
occupancy input.  
The H1 and H2 holidays will not be influenced if the user  
changes the actual date. If power supply is interrupted for  
more than one day, all H1 and H2 holidays within the date of  
power supply error and the actual date will be deleted.  
Table 14 shows an example of the weekly schedule  
programmed with the following default values:  
•
•
Mo ... Su from 6:00 till 18:00 = Comfort mode  
Mo ... Su from 18:00 till 6:00 = Night mode  
The holiday schedule is used to program each day of the year  
01.01 ... 31.12.) as a holiday (day type = H1, H2 or H3) or as  
point 1 point 2 point 3  
(
1
)
point 4  
point 5  
point 6  
day  
2)  
2)  
2)  
2)  
2)  
2)  
time  
6:00  
6:00  
6:00  
6:00  
6:00  
6:00  
6:00  
0:00  
0:00  
0:00  
SMode  
time  
SMode  
time  
SMode  
time  
SMode  
time  
SMode  
time  
SMode  
night  
night  
night  
night  
night  
night  
night  
Mo  
comfort  
comfort  
comfort  
comfort  
comfort  
comfort  
comfort  
off  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
--:--  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
ignore  
18:00  
18:00  
18:00  
18:00  
18:00  
18:00  
18:00  
--:--  
Tu  
We  
Th  
Fr  
Sa  
Su  
H1  
H2  
H3  
ignore  
ignore  
ignore  
off  
--:--  
off  
--:--  
1
)
2)  
Weekday or holiday type; Programmed controller mode (schedule mode)  
Table 14. Example of weekly schedule and holiday types (default)  
day  
Jan.  
H0  
Feb.  
H0  
March  
H0  
April  
H0  
May  
H3  
June  
H0  
July  
H0  
August Sept.  
Oct.  
H0  
Nov.  
H0  
Dec.  
H0  
1.  
2.  
3.  
4.  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H1  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H1  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H1  
H0  
H0  
H0  
2
2
3
3
8.  
9.  
0.  
1.  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H1  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
H0  
1
)
H0  
1
)
th  
If the 29 of February is programmed to be a H1 or H2 holiday and the current year is not a leap year, this holiday will be  
deleted on March 1.  
Table 15. Example of annual schedule (no default)  
EN1B-0203GE51 R0507C  
16  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
Selecting Clock and Schedules (with RTC, only)  
Programming Standard Schedule (with RTC, only)  
The standard schedule programming is used to program up to  
6 schedule points for each weekday as well as for three  
holiday types. The controller mode (off, night, standby or  
comfort) will be switched at these programmed schedule  
points.  
DATE & TIME  
SELECTION  
DATE & TIME  
ADJUSTMENT  
The first step of the schedule programming (see Fig. 15) is to  
select a weekday or holiday type as follows:  
STANDARD  
SCHEDULE  
SELECTION  
STANDARD  
SCHEDULE  
PROGRAMMING  
1
2
3
. Mo ... Su as single  
. H1 ... H3 as single  
. Mo ... Fr grouped  
HOLIDAY  
SCHEDULE  
SELECTION  
HOLIDAY  
SCHEDULE  
PROGRAMMING  
4. Sa and Su grouped  
. Mo ... Su grouped  
5
The switching time is adjustable in steps of 10 min. To ignore  
a schedule point, the displayed switching time must be set to  
Fig. 13. Clock and schedules selection mode  
‘
--:--’ by adjusting it between step 23:50 and 0:00 or by  
The clock and schedule selection mode is provided to select  
real-time clock (RTC), standard schedule (SCH), or holiday  
schedule (Hol) for programming (see Fig. 13).  
pushing the and button simultaneously.  
+
-
Pushing the SEL button returns to the selection mode,  
ignoring adjustments which have not been confirmed by the  
SET button.  
Pushing the  
+ or - button scrolls through the selection list.  
Adjusting Date and Time (with RTC, only)  
TO SELECT  
WEEKDAY,  
WEEK GROUPS,  
OR HOLIDAY  
TYPES  
This mode is used to adjust date and time (real-time clock) by  
the input sequence shown in Fig. 14.  
OR  
OR  
OR  
OR  
During date adjustment, the weekday is calculated auto-  
matically and need not be programmed. The 29th of February  
is adjustable only for leap years.  
TO ADJUST  
SCHEDULE  
POINT  
Pushing the SEL button returns to the selection mode,  
ignoring adjustments which have not been confirmed by the  
SET button.  
Tu  
Tu  
Tu  
Due to battery change or low battery, the date / time can be  
invalid and is displayed as --.--. --  
/
--:-- on the LCD. In this  
TO ADJUST  
SWITCHING  
TIME  
case the controller behaves like a controller without real-time  
clock. If the occupancy input is inactive, the controller will be  
assumed as occupied.  
TO ADJUST  
CONTROLLER  
MODE  
TO ADJUST  
HOURS  
OR  
TO ADJUST  
MINUTES  
OR  
Fig. 15. Standard schedule programming  
Date  
TO ADJUST  
YEAR  
OR  
Date  
TO ADJUST  
MONTH  
OR  
Date  
TO ADJUST  
DAY  
OR  
Fig. 14. Date and time adjustment mode  
1
7
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
Programming Holiday Schedule (with RTC, only)  
Interpreting Error Messages  
The holiday schedule programming is used to program each  
day of the year (01.01 ... 31.12.) as a holiday (day type = H1,  
H2 or H3) or as a normal day (day type = H0 is default).  
Different analog input errors can be identified by the controller  
(
Error handling). The defective analog input (T1, T2, T3 or  
Xwrh) will be displayed in the standard display mode (see Fig.  
7) after the corresponding value is selected.  
1
Pushing the  
+ or - button during the first step of the holiday  
programming (see Fig. 16) toggles between all programmed  
NOTE: For the external CPA/SPA potentiometer input, no  
error message is indicated if the potentiometer or  
wiring is defective. In this case, for control point or  
setpoint calculation, the following values are used:  
holidays (≠ H0) and displays them (type and date).  
If none of the 365 days of a year is programmed to be a  
holiday, the actual date is displayed, marked as normal day  
•
•
for CPATYP 0, 1 or 2 ⇒ CPA value = 0  
for CPATYP 3 ⇒ SPA value = control parameter W1  
(
H0).  
Pushing the SET button selects the displayed holiday and  
enters the adjustment for date and day type.  
DISPLAY SHOWN IF NO SENSOR  
IS CONNECTED DURING POWER-UP  
DISPLAY SHOWN AFTER ERROR  
IDENTIFICATION DURING OPERATION  
To program a new holiday, select any holiday, adjust date  
(and holiday type if necessary) and confirm the changes by  
pushing the SET button. To reset a holiday to normal day, day  
type H0 has to be set for the specific day.  
°
C
%
rh  
°C % rh  
STANDARD  
DISPLAY  
STANDARD  
DISPLAY  
Pushing the SEL button returns to the selection mode,  
ignoring adjustments which have not been confirmed by the  
SET button.  
AND  
AND  
AND  
: MAIN TEMPERATURE SENSOR T1 IS DEFECTIVE  
TO  
TOGGLE/DISPLAY  
: LIMITATION OR CASCADE TEMPERATURE SENSOR T2 IS DEFECTIVE  
: COMPENSATION TEMPERATURE SENSOR T3 IS DEFECTIVE  
: ERROR OF HUMIDITY DEVIATION INPUT XWrh  
OR  
PROGRAMMED  
HOLIDAY  
We  
SPACE AND  
TEMPERATURE DISPLAY IN °C  
HUMIDITY DEVIATION DISPLAY IN % rh  
TO ADJUST  
MONTH  
OR  
OR  
OR  
Fig. 17. Error handling  
Sa  
A
B
PUSH  
SIMULTANEOUSLY  
FOR APPROX.  
PUSH UNTIL  
NEEDED  
VALUE IS  
TO ADJUST  
DAY  
STANDARD  
DISPLAY  
MODE  
°C  
Th  
2
SEC  
DISPLAYED  
PARAMETER  
ADJUSTMENT  
MODE  
°C  
°C  
TO ADJUST  
DAY TYPE (H0,  
H1, H2, OR H3)  
We  
PARAMETER  
SELECTION  
MODE  
°C  
PARAMETER  
SELECTION  
MODE  
°C  
Fig. 16. Holiday schedule programming  
B
A
THIS EXAMPLE DESCRIBES THE ADJUSTMENT OF THE  
COMPENSATION CHANGEOVER POINT Wcomp (P03).  
Fig. 18. Adjustment example  
EN1B-0203GE51 R0507C  
18  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
NOTES (WITH RTC, ONLY)  
)
day  
Jan.  
Feb.  
March  
April  
May  
June  
July  
August Sept.  
Oct.  
Nov.  
Dec.  
1
2
3
4
5
6
7
8
9
1
.
.
.
.
.
.
.
.
.
0.  
1.  
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
2.  
3.  
4.  
5.  
6.  
7.  
8.  
9.  
0.  
1.  
2.  
3.  
4.  
5.  
6.  
7.  
8.  
9.  
0.  
1.  
1
)
1
)
th  
If the 29 of February is programmed to be a H1 or H2 holiday and the current year is not a leap year, this holiday will be  
deleted on March 1.  
Table 16. Annual schedule  
1
9
EN1B-0203GE51 R0507C  
href="
R7426A,B,C TEMPERATURE CONTROLLER WITH AND WITHOUT REAL-TIME CLOCK  
point 1  
time SMode  
point 2  
time SMode  
point 3  
time SMode  
point 4  
time SMode  
point 5  
time SMode  
point 6  
2)  
time SMode  
1)  
day  
2)  
2)  
2)  
2)  
2)  
Mo  
Tu  
We  
Th  
Fr  
Sa  
Su  
H1  
H2  
H3  
1
)
2)  
Weekday or holiday type; Programmed controller mode (schedule mode)  
Table 17. Weekly schedule and holiday types  
Manufactured for and on behalf of the Environmental and Combustion Controls Division of Honeywell Technologies Sàrl, Ecublens, Route du Bois 37, Switzerland by its Authorized Representative:  
Automation and Control Solutions  
Honeywell GmbH  
Böblinger Straße 17  
D-71101 Schönaich  
Phone: (49) 7031 63701  
Fax: (49) 7031 637493  
http://europe.hbc.honeywell.com  
Subject to change without notice. Printed in Germany  
EN1B-0203GE51 R0507C  
Manufacturing location certified to  

Honeywell CT87N Thermostat User Manual

Honeywell TH8321U1006 Thermostat User Manual

Honeywell TH6220D1002 Thermostat User Manual

Honeywell CT1802 Thermostat User Manual

Honeywell T694B Thermostat User Manual

Honeywell Y8196A Thermostat User Manual

Aube TH115 F Thermostat User Manual

White Rodgers 50A55 474 Thermostat User Manual

White Rodgers T26 Thermostat User Manual

Honeywell Q674L Thermostat User Manual