Swegon BELIMO ZTH-GEN Guide

1
VARd
Installation - Commissioning - Maintenance 20111011
Contents
Installation – Wiring guides Pages 2-7
Commissioning - Flows Pages 7-8
How to use the VAR 1 Pages 9-10
How to use the VAR 2 Pa ges 10 -11
How to use the VAR 4 Pages 12-13
How to use the VAR 5 Page 13
Dimensions and weights Page 14

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1
2
Lengths of straight duct upstream of the VAR for
rectangular ducts
Type of obstruction For m2= 5% For m2= 10%
One 90° bend 3 x B 2 x B
T piece 3 x B 2 x B
Baffle-type sound attenuator 3 x t 2 x t
t = Thickness of the baffle
Figure 5. Installation with a length of straight duct applies to both
the supply air and the extract air. The figure shows the extract air
variant. In an arrangement for supply air, the length of straight
duct should be 500 mm downstream of the VAR. 1 = A ≥500 mm
length of straight duct. 2 = Sound attenuator with sound baffles
Figure 4. Installation demands a length of straight duct A > 2 x B
1. VAR Variable-flow commissioning damper
Figure 2. Variable-flow commissioning damper, VAR (1) with FSR
fixing clamp (2) and sound attenuator (3).
If the sound attenuator is equipped with a sound baffle or
centre body, it should be installed at a distance 2 x the duct
diameter (ØD) upstream or downstream of the VAR. This
applies to both supply air and extract air.
Figure 1. Permitted ambient temperature.
Installation - Wiring
Figure 3. Variable-flow commissioning damper, VAR (1) with FSR
fixing clamp (2).
Installation dimensions
Size ASize A
100 472 250 522
125 472 315 552
160 472 400 684
200 472 500 810 Figure 6. Open space for installation

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Figure 9. Wiring diagram for VAR 4.
Colour codes: 1 = Red, 2 = Black, 8 = grey, 9 = Pink
Insulate any conductors not in use.
Important!
It is important to connect system ground correctly. On
the Belimo products system ground is on wiring terminal
(conductor) 1 and on the Siemens products it is on termi-
nal (conductor) 2. For all of these, the neutral conductor
has black insulation.
U
1235
~Y
24V AC 0-10 alt. 2-10 V DC
MP-bus
NMV-D3-MP SWN
LMV-D3-MP SWN
a
d
b
2-10 V DC
-+PP Z1 Z2
0-10 alt. 2-10 V DC
2-10 V DC
Controller configuration
VAR 1 = Belimo LMV-D3-MP SWN, NMV-D3-MP SWN
VAR 2 = Belimo VRD 3 SWN
VAR 4 = Siemens GLB181.1E/3
Electrical data
Key to Figures 7-9.
a = fully open damper
b = fully closed damper
c = preset min. airflow
d = preset max. airflow
Wiring diagrams
Figure 8. Wiring diagram for VAR 2.
Figure 7. Wiring diagram for VAR 1.
Colour codes: 1 = Black, 2 = Red, 3 and 5 = White
Insulate any conductors not in use.
VAR 1 (Belimo compact)
Supply voltage 24 V AC ±20%, 50-60 Hz
Supply voltage 24 V DC ±10%
Controller and motor 6 VA
Input 3, resistance 100 kOhm
Input 3, control signal 0-10 alt. 2-10 V DC
Output 5, true value 2-10 V DC max. 0.6 mA
Ambient air temperature,
operation
0 °C - +50 °C
VAR 2 (Belimo Universal)
Supply voltage 24 V AC ±20%, 50-60 Hz
Supply voltage 24 V DC ±10%
Controller and motor 9.5 VA
Input 3, resistance 100 kOhm
Input 3, control signal 0-10 alt. 2-10 V DC
Output 5, true value 2-10 V DC max. 0.6 mA
Ambient air temperature,
operation
0 °C - +50 °C
VAR 4 (Siemens)
Supply voltage 24 V AC ±20%, 50-60 Hz
Controller and motor 6 VA
Input YC, resistance 100 kOhm
Input YC, control signal 0-10 V DC
Input YC if DC = -1.5 to -0.2 V closes the damper
Input YC, limitations, max. 11 V DC
Output UC, true value 0-10V DC max 1 mA
Ambient air temperature,
operation
0 °C - +50 °C

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Wiring example
If the VAR is used as a constant-flow commissioning
damper, only 24 V AC current should be connected to the
controller. A number of different wiring examples with vari-
ous types of control are shown on the following pages.
˚C+C02
C02 ˚C
DETECT Q 1 & 2
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
VARVAR
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
VARVAR
RTCRTCT
Room thermostat
Figure 10. The diagram shows how to wire the VART room ther-
mostat with simultaneous control of the extract air. The figure
also shows an alternative with RTCT duct temperature sensor.
1 = VAR Supply air.
2 = VAR Extract air.
CO2and temperature control
Figure 11. The diagram shows how to wire the CO2sensor with combined
DETECT Q temperature control and simultaneous control of the extract air.
1 = VAR Supply air.
2 = VAR Extract air.

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Two-flow control with presence detector
The diagram shows how to wire the DETECT O presence
detector with simultaneous control of the extract air.
Two-flow control, min. or max. airflow.
Figure 12. Wiring diagram, VAR 1 (Belimo Compact).
1 = VAR Supply air.
2 = VAR Extract air.
Y
LMV-D3-MP SWN
NMV-D3-MP SWN
LMV-D3-MP SWN
NMV-D3-MP SWN
DETECT O
VARVAR
YU U
DETECT OVA
RV
AR
+-
Figure 14. Wiring diagram, VAR 4 (Siemens).
1 = VAR Supply air.
2 = VAR Extract air.
VRD2
Ser
Actuator
VRD3
Figure 13b. Jumper configuration, VAR 2
(Belimo Universal).
VRD2 = DETECT O controls to fully open
damper
VRD3 = DETECT O controls to preset flow for
V-max.
Figure 13a. Wiring diagram, VAR 2 (Belimo Universal).
1 = VAR Supply air.
2 = VAR Extract air.
DETECT O
-+-+
VA
RV
AR
12
U5 U5

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VAV regulation and heat regulation with thermo-actuators
Figure 17. The diagram shows how to wire and refit jumpers of the RTC room ther-
mostat enabling operation of the on/off 24 V VAC thermo-actuator on output YH (4).
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
VARRTCVARRTCT
-+
VRD3 SWN
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
VART 5
VAR
G0
2
G
1
YC
8
YC
9GLB181.1E/3
Slave control with VART 5 as master
Figure 16. The diagram shows the connections between master – slave unit.
In this wiring configuration, the VAR slave controller should be set to a flow
range of 0-100% of the nominal airflow.
1 = VAR Supply air.
2 = VAR Extract air.
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
LMV-D3-MP SWN
NMV-D3-MP SWN
VRD3 SWN
DETECT O
VARVAR
RTC
VAV regulation with room thermostat and presence detector
1 = VAR supply air.
2 = VAR Extract air.
3 = Thermo-actuator, heating.
Figure 15. The diagram shows how to wire the RTC room thermostat, DETECT O with
simultaneous control of the extract air. VAV is used for occupancy, otherwise min.
airflow. The figure also shows the alternative with RTCT duct temperature sensor.

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Jumper connection - RTC
The jumper connection in the RTC must be changed
when you wire the thermo-actuator (3) to the system. See
the figures below. A maximum of 4 thermo-actuators are
permitted to be wired to the same output.
N.B.! The unit must be de-energized before you recon-
nect any jumpers!
More information on the RTC can be read in its Installa-
tion – Commissioning Instructions.
Figure 19. Jumper connection for thermo-actuator, heat.
YK = Cooling energy regulation: 0-10V DC
YH = Heat regulation: 024V DC
Figure 18. Jumper connection, Delivery settings.
YK = Cooling energy regulation: 0-10V DC
YH = Heat regulation: 0-10V DC
Nom flow = 170 l/s
VARd 1-160
k-factor = 15,5
170 l/s
Commissioning - Flows
General points for all types
The VAR variable-flow commissioning dampers are
factory-calibrated and are normally preset for the airflow
range specified for the project. The setting values can be
read on the product rating plate affixed on both sides of
the product. Installation info and electrical connections
are described in these instructions. For the best perfor-
mance, it is extremely important that the requirement
for lengths of straight duct upstream or downstream of
the VAR is complied with. If you arrange only half of the
required length of straight duct, this may increase the
control tolerance from 5 up to 20%. The airflow direction
should always be such that the damper is fitted down-
stream of the flow measuring device. The unit’s rating
plate includes air direction arrows.
Control signals
All the electronic VAR devices are designed for a signal
range of 0-10V DC. Any deviation from this range is
indicated on the product rating plate. If a direct-wired
room thermostat is used for controlling the airflow
requirements, then a control voltage of <0.5V implies the
min. airflow that is preset in the controller and 10 V then
produces the max. airflow. It is common that the control
is carried out via a controller that then manages the min./
max. airflow setting by limiting the control signal e.g.
from 2.3 – 7.6 Volt DC. If wired to a controller, the VAR is
normally set to 0-100% of its operating range. N.B. In some
cases, high airflows can generate increased sound levels.
Figure 20. Shows the product rating plate.
Formulas for calculating airflows.
Formula 1, where Q = l/s and Y = control voltage.
Formula 2, where Q = l/s and U = true value voltage.
If the true value signal is used, the airflow should be
worked out with Qnom.
Airflows
The VAR has a nominal air flow, Qnom for each size.
The maximum air flow can be set to between 30 and
100% of Qnom.
The minimum air flow can be adjusted in relation to Qnom
and can be set to between 0 and 100% of Qnom.
The regulators cannot manage air flows less than Qmin,
as the manometer reading then becomes too low and
regulation ceases.
VAR 1, 2 and 4 can be supplied in special versions with
larger max. flow, up to 200 Pa read on the manometer.
The consequence of this is less accuracy in the lower range.

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Airflow and K-factor
Size Airflows (l/s)
Qmin (5Pa) Qnom/max (120Pa) K-factor
100 12 58 5.3
125 19 95 8.7
160 35 170 15.5
200 55 272 24.8
250 89 438 40.0
315 142 695 63.4
400 228 1117 102.0
500 367 1797 164.0
200 x 200 75 367 33.5
300 x 200 112 548 50.0
400 x 200 149 728 66.5
500 x 200 187 915 83.5
600 x 200 224 1095 100.0
700 x 200 262 1282 117.0
800 x 200 297 4157 133.0
1000 x 200 373 1829 167.0
300 x 300 170 833 76.0
400 x 300 228 1117 102.0
500 x 300 284 1391 127.0
600 x 300 340 1665 152.0
700 x 300 398 1950 178.0
800 x 300 454 2224 203.0
1000 x 300 568 2782 254.0
400 x 400 304 1490 136.0
500 x 400 382 1873 171.0
600 x 400 458 2246 205.0
700 x 400 534 2618 239.0
800 x 400 610 2991 273.0
Size Airflows (l/s)
Qmin (5Pa) Qnom/max (120Pa) K-factor
1000 x 400 762 3735 341.0
1200 x 400 915 4480 409.0
1400 x 400 1069 5236 478.0
1600 x 400 1221 5981 546.0
500 x 500 479 2344 214.0
600 x 500 575 2815 257.0
700 x 500 671 3286 300.0
800 x 500 767 3757 343.0
1000 x 500 959 4699 429.0
1200 x 500 1149 5631 514.0
1400 x 500 1342 6573 600.0
1600 x 500 1534 7515 686.0
600 x 600 691 3385 309.0
700 x 600 807 3955 361.0
800 x 600 921 4513 412.0
1000 x 600 1152 5642 515.0
1200 x 600 1382 6770 618.0
1400 x 600 1614 7909 722.0
1600 x 600 1845 9037 825.0
700 x 700 944 4623 422.0
800 x 700 1078 5280 482.0
1000 x 700 1348 6606 603.0
1200 x 700 1617 7920 723.0
1400 x 700 1887 9246 844.0
1600 x 700 2156 10560 964.0
1600150014001300
1200
11001000900800600 700 400 500
200 300
0
100
2
6
4
10
8
U Volt
l/s
Ø500
Ø400
Ø315
Ø250
Ø200
Ø160
Ø125
Ø100
Diagram, true value voltage/airflow
The diagram is applicable only to factory-calibrated
products for nominal airflow according to the Airflow and
K-factor (COP) Table.

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VAR 1
Checking the performance
Start
A 3-minute warm-up period is required when you switch
on the voltage (cold start) before the controller will oper-
ate normally.
Important!
The motor section on the LMV-/NMV D3 MP SWNP has a
release button that in the depressed position enables you
to turn the shaft by hand, but in doing so the controller
loses control over the damper blade position. When you
release the button, the controller automatically synchro-
nises the damper blade position.
Checking the min. airflow
This can be done most simply by disconnecting the white
cable marked 3. The damper will then move to the closed
position. This position is conditional on the bearing pres-
sure and the preset min. airflow rate. Measure the voltage
U and calculate the airflow using Formula 2 on page 7.
Checking the max. airflow
Use the room thermostat or some other control equip-
ment to override the system so that the control voltage
will be a 10 V input on white cable 3. As an alternative
you can short circuit between cables 2 and 3. This will
steer the controller to the preset max. airflow setting.
Before short circuiting, you must disconnect the cable
from the room controller. If this is not done, you will
destroy the output on the control equipment. The damper
will move to the open position. Measure the voltage U
and calculate the airflow using Formula 2 on page 7.
Figure 21. Shows how to connect a voltmeter for checking the
true value.
Figur. 22 ZTH-GEN hand-held micro terminal.
VAR 1 as a constant-flow controller
VAR 1 can be used as a constant-flow controller in two
ways. It is most appropriate to use the min. flow setting
as the set point for the constant airflow. 24 V AC only
should be connected to cable pair 1 and 2. You can also
use the max. airflow setting, however you must then
provide for a short circuit between cables 2 and 3. See
under: Checking the max. airflow.
Changing the LMV-/NMV D3 MP SWN settings
The min./max. airflow should be calculated and set as
follows:
Qmax % required max. airflow (Qmax) divided by nominal airflow
(Qnom).
Qmin % required min. airflow (Qmin) divided by maximum
airflow (Qmax).
Example:
VAR, dim. Ø160, required min./max. airflows: 51/119 l/s.
Qmax % = Qmax / Qnom => 119/170 = 0.70 = 70%
Qmin % = Qmin / Qnom => 51/170 = 0.30 = 30%
Qnom can be read in Table 1 on page 9
The min./max. settings and the 0-10 or 2-10 signal level
settings can be changed by means of various instruments.
ZTH-GEN hand-held micro terminal
It is simple to check and change the preset airflows with the
hand-held micro terminal. The hand-held micro terminal has
a configuration menu for setting the language and the units.
3,52 V
V DC
U
1235
~w1 NMV-D3MP
SWN

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VAR 2
Checking the performance
Start
A 3-minute warm-up period is required when you switch
on the voltage (cold start) before the controller will oper-
ate normally.
Checking the min. airflow
This can be done by disconnecting the control signal cable
from terminal 3. The damper will then move to the closed
position. This position is conditional on the bearing pres-
sure and the preset min. airflow rate. Measure the voltage
U and calculate the airflow using Formula 2 on page 7.
Checking the max. airflow
Use the room thermostat or some other microprocessor
substation equipment to override the system so that the
control voltage will be a 10 V input on terminal 3. As an
alternative you can short circuit between terminals 2 and
7. This will steer the controller to the preset max. airflow
setting. The damper will move to the open position.
Measure the pressure in the pressure tapping and calcu-
late the airflow using the K-factor for the relevant size.
Measure the voltage U and calculate the airflow using
Formula 2 on page 7.
The VAR 2 as a constant-flow controller
The VAR 2 can be used as a constant-flow controller in
two ways. It is most appropriate to use the min. flow
setting as the set point for the constant airflow. 24 V AC
only should be connected to cable pair 1 and 2. You can
also use the max. airflow setting, however you must then
provide for a short circuit between cables 2 and 7. See
under: Checking the max. airflow.
Trouble shooting
Incorrect polarity on control signal zero conductor
It is important that the neutral conductor follows the
entire chain of connections from thermostat to control-
ler. Check this by measuring the control voltage between
cables 1 and 3 on the VAR. Correctly wired it should be
possible to vary the signal between 0-10 V DC. If incor-
rectly wired the signal will be ~ 8 - 14 V DC. The follow-
ing values apply to the RTC: ~ 5-10 V DC.
Start menu of the VAV controller
Start: Connect the cable provided to the VAV
controller
Reply: The type of controller connected appears in
the display window
"OK" button The serial number of the controller is shown
"+" button The program version of the controller is
shown
Select fun-
ction:
▼▲ Navigate forward/backward to scroll
between the various menu positions (see
table below)
Exit: Disconnect the cable to the VAV controller
PC-TOOL
A PC-based program can be used for checking performance
and changing settings. PC-Tool version 3.0 or later is required.
This is simpler since contact with the controller takes place
with a separate bus cable, no reconnection is required (Plug
And Play). Contact Swegon’s representative for further info.
Configuration menu of the ZTH-GEN
Start: Hold the (OK) button depressed and at the
same time connect to the VAV controller.
Answer: "Configuration menu"appears in the display
window
Select setting Press the ▼button (see selection below)
Choice of
language
German*/English
Choice of unit m3/h *, l/s, cfm
Voltage DC/AC 24 V (shows current supply voltage)
MP test Shows the pulse train in the network (for
system integrator)
Expert mode 0 */ 1 (provides expanded access to settings)
Advanced
mode
0 */ 1 (provides expanded access to settings)
Exit Via menu selection (returns automatically to
the mode for configuring the VAV controller)
or for removing the connection to the VAV
controller. The selected settings are automa-
tically stored in the ZTH.
Airflow does not correspond
This is almost always due to that the requirements for
lengths of straight ducting upstream/downstream of the
VAR have not been met. If the ducting deviates from these
requirements, the error can be as much as 20%. The flow
measurement sensor may become fouled in systems with
considerable dusty air (most often extract air systems).
This however doesn’t occur until the system has been
operating for 3-5 years. The sensor can be cleaned by
blowing it with clean air in the opposite direction, i.e. in
the minus tube connection. We recommend compressed
air in a low-pressure aerosol tube. The duct must also be
cleaned so that the flow measurement stick and the pres-
sure tappings are not clogged.

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3,52 V
V DC
-+PP Z1 Z2
Figure 23. Shows how to connect a voltmeter for checking the
true value.
Trouble shooting
Incorrect polarity on control signal zero conductor
It is important that the neutral conductor follows the
entire chain of connections from thermostat to control-
ler. Check this by measuring the control voltage between
cables 1 and 3 on the VAR. Correctly wired it should be
possible to vary the signal between 0.5-10 V DC. If incor-
rectly wired the signal will be ~ 8 - 14 V DC; for the RTC
the signal will be ~ 2 - 8 V DC.
The airflow does not agree
This is almost always due to that the requirements for
lengths of straight ducting upstream/downstream of the
VAR have not been met. If the ducting deviates from these
requirements, the error can be as much as 20%. The flow
measurement sensor may become fouled in systems with
considerable dusty air (most often extract air systems). This
however doesn’t occur until the system has been operating
for 3-5 years. The sensor can be cleaned by blowing it with
clean air in the opposite direction, i.e. in the tube connec-
tion. We recommend compressed air in a low-pressure
aerosol tube. The duct must also be cleaned so that the
measurement flange and the pressure tappings are not
clogged.
Changing the settings
The min./max. airflow values are calculated and set as
follows:
Qmax % required max. airflow (Qmax) divided by nominal airflow
(Qnom).
Qmin % required min. airflow (Qmin) divided by nominal airflow
(Qnom).
Example:
VAR, dim. Ø160, required min./max. airflows: 51/119 l/s.
Qmax % = Qmax / Qnom =>119/170 = 0.70 = 70%
Qmin % = Qmin / Qnom => 51/170 = 0.30 = 30%
Qnom is read from Table 1 on page 9.
Enter the settings directly in the controller. No external
instrument is needed but the settings can also be adjusted
with Belimo’s instrument, ZTH-GEN.
Configuration menu ZTH-GEN
Start: Hold the (OK) button depressed and at the
same time connect to the VAV controller.
HW Version
SW Version
Indicates which hardware or software ver-
sion the unit runs
Reply: "Configuration menu"appears in the display
window
Select setting Press the ▼button (see selection below)
Choice of
language
German*/English
Choice of unit m3/h *, l/s, cfm
Voltage DC/AC 24 V (shows current supply voltage)
MP test Shows the pulse train in the network (for
system integrator)
Expert mode 0 */ 1 (provides expanded access to settings)
Advanced
mode
0 */ 1 (provides expanded access to settings)
Exit Via menu selection (returns automatically to
the mode for configuring the VAV controller)
or for removing the connection to the VAV
controller. The selected settings are automa-
tically stored in the ZTH.
Start menu of the VAV controller
VRD3 SWN Indicates to which controller the ZTH-GEN is
connected.
Volume 0%
Setpoint 0%
Shows the true value in % of the nominal fl
ow Shows the calculated
set point
Volume 0%
Pressure 0Pa
Shows the true value in % of the nominal flow
Shows the manometer pressure in Pa
Volume 0%
CAV-Step
Shows the true value as a percentage of the
nominal Auto, Open, Close, Vmax, Vmin, Stop
Mode 0.0-10.0
-new:
Shows the current operating range for control
signalRange for control signal 0-10V or 2-10 V
Vmin
-new
Set point for min. flow in %
Set point (potentiometer in tool area)
Vmax
-new
Set point for max. flow in %
Set point (potentiometer in tool area)
Vnom Shows nominal flow in %
p@Vnom Shows nominal flow in Pa

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Figure 24. Shows the calibration time diagram.
A = Calibration no.
B = Time after energizing (min).
3,52 V
V DC
12 89
GLB181.1E/3
GG0YCUC
6
Y1
7
Y2
Figure 25. Shows how to connect a voltmeter for checking the
true value.
Forcing the commissioning damper to the fully
closed position:
Fit a jumper on G0 (black cable marked 2) with Y2
(orange cable marked 7). The actuator should close for a
maximum period of 150 seconds.
To force the commissioning damper to the fully
open position:
Fit a jumper on G0 (black cable marked 2) with Y1 (violet
cable marked 6). This is most easily done by disconnecting
the grey cable for the control signal marked 9.
To override with the AST setting instrument
The Y signal can also be set from the AST 10 hand-held
micro terminal. Press Y button and change the signal to
10 V with the – or + keys on the side of the display. To
acknowledge by pressing SET. When you disconnect the
Setting instrument, you also remove the means of overrid-
ing the system.
The VAR 4 as a constant-flow controller
When the VAR 4 is to be used as a constant flow
controller,this can be done in two ways . It is appropriate
to use the min. flow setting as the set point for the con-
stant airflow. 24 V AC only should be connected to the
cable pair 1 and 2. You can also use the max. airflow set-
ting, however in this case you must make a short circuit
between 2 and 3, see under Checking the max. airflow.
Important!
The release button on the unit must not be used when the
unit is energized. If this occurs, the controller will lose its
positioning capability and you will have to de-energize the
unit for at least five seconds to remedy the situation. If you
want to test or force the commissioning damper, use the
jumper connections shown below or use the AST 10 hand-
held micro terminal.
Checking the min. flow:
If possible, zero volt is transmitted from the room unit or the
main control system. If this possibility is lacking, then discon-
nect YC (grey cable, marked 8). Measure the pressure in the
pressure tapping and calculate the airflow using the K-factor
for the relevant size. Check also the max. airflow.
Regulating the commissioning damper to max. flow:
If possible, 10 volt is transmitted from the room unit or
the main control system. If this possibility is lacking, then
disconnect YC (grey cable, marked 8), fit a jumper on G0
(black cable marked 2) with Y2 (orange cable marked 7)
and Y1 (violet cable marked 6).
VAR 4
Checking the performance
Start
After energizing the system, the VAV unit calibrates the
pressure sensor as illustrated in the diagram below. Each
calibration takes 90 seconds and the unit is then idle. This
means that the user should not precision adjust the min.
and max. airflows with the AST 10 hand-held micro termi-
nal, if required, until after three hours after energizing to
avoid that the unit is idle too often. There is no in-opera-
tion indicator that shows that zero calibration is in progress.
To change the settings
The min./max. airflow should be calculated and set as
follows:
Qmax % required max. airflow (Qmax) divided by nominal airflow
(Qnom).
Qmin % required min. airflow (Qmin) divided by nominal airflow
(Qnom).
Example:
VAR, dim. Ø160, required min./max. airflows: 51/119 l/s.
Qmax % Qmax / Qnom = 119/170 = 0.70 = 70%
Qmin % Qmin / Qnom = 51/170 = 0.30 = 30%
Qnom can be read in Table 1 on page 9.

13
VAR
Swegon reserves the right to alter specifications. 20111011 www.swegon.com
Figure 26. AST 10 hand-held micro terminal.
3,52 V
V DC
-+PP Z1 Z2
VART 5
Checking the performance
Start
A 3-minute warm-up period is required when you switch
on the voltage (cold start) before the controller will oper-
ate normally.
Checking signals
Since the VART 5 uses only the controller’s airflow meas-
urement feature, no settings are needed. It is the true value
signal from terminal 5 that must be wired further to the
slave unit. This is not affected by the settings on the min./
max. potentiometers.
Measure the voltage, U, and calculate the airflow using the
formulas below for the relevant signal system; 0-10 or 2-10
V DC. VART 5 is normally supplied with a 0-10 true value
signal. Check the marking to see whether it should be set
for 2-10 V.
For Qnom see the table on page 8.
Figure 28. Shows how to connect a voltmeter for checking the
true value.
Figure 27. Formula for calculating the airflow
AST 10 Hand-held micro terminal
The AST 10 enables you to read the current data in air-
flow and control signal form. The user can easily change
the min./max. settings in the AST 10. Connect the cable
provided to the hand-held micro terminal and to the
actuator. Be careful when connecting the contact pins
to avoid damaging them. Older actuator models lack a
quick-fit connector. Therefore use the triple wire and con-
nect it to the same terminal that the motor conductors
are connected to. See the wiring diagram for the AST 10
supplied in the instrument case.
1. Press on Vmax change to the required value % with the
+ / - buttons - press SET to confirm the change.
2. Press on Vmin change to the required value % with the
+ / - buttons - press SET to confirm the change.
3. With Yyou can read the control voltage (set point)
transmitted from the room thermostat.
4. By pressing the arrow keys under the display, you can
navigate between the various signal values. U shows
the true value voltage.
5. By pressing on Factory set you can reset the factory
preset values.
Trouble shooting
Incorrect polarity on control signal zero conductor
It is important that the neutral conductor follows the entire
chain of connections from thermostat to controller. Check
this by measuring the control voltage between cables 2
(black) and 8 (grey) on the VAR. Correctly wired it should be
possible to vary the signal between 0-10 V DC. If incorrectly
wired, the signal will be ~ 6.5 - 14 V DC. The following
values apply to the RTC: ~ 3-10 V DC. N.B.! This must be
measured with a voltmeter. The AST instrument shows other
values on the display for Y.
No regulation
This may occur when the controller is in a calibration phase.
During the calibration phase, the letter S is visible in the upper
right corner of the display. If still nothing happens, discon-
nect the red pressure tube and carefully blow in the control-
ler tapping. As a final measure, interrupt the voltage supply
for about one minute. If the controller still will not operate,
replacing it is inavoidable.

14
VAR
Swegon reserves the right to alter specifications. 20111011 www.swegon.com
Dimensions and weights
VAR 1, 2 and 4
50
210
Ø D
92
Size Ød A B C E H L Weight, kg Weight, kg
mm mm mm mm mm mm mm Uninsulated VAR Insulated VAR
100 99 472 245 61 90 180 401 2.6 3.9
125 124 472 245 61 77 180 401 2.9 4.0
160 159 472 285 61 60 215 401 3.3 4.8
200 199 472 335 61 40 255 401 4.0 5.8
250 249 522 395 61 15 305 452 4.9 7.8
315 314 552 465 61 -370 452 6.5 9.7
400 399 684 553 61 -462 614 10.7 14.9
500 499 810 653 61 -565 740 15.7 21.3
250
Figure 34. VART 5, rectangular.
Figure 33. VAR 4, circular.
Figure 32. VAR 1-IR, rectangular (insulated casing).
Figure 31. VART 5, circular.
Figure 30. VAR 2, circular.
Figure 29. VAR 1, circular.