Lindab DRU User manual

lindab | we simplify construction
Assembly instructions
LindabDampers

2
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lindab | we simplify construction
DTBCU, DTFU, DTBLU, DSUSN, DSVUSN, DTPU, PSDRU, TDRU, TDSU
TASU, TATU, TATBU, LKSR
DAU, DA2EU, DAVU, CARU, CAR, MBU, MBFU
DRU, DSU, DTU, DTHU, DTH1U, DTH2U, DTBU, DTBVU
Dampers

3
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FMU, FMDRU, FMDU, DIRU, DIRBU, DIRVU
FTCU, FTMU, FTSU
Dampers

4
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Dampers
DRU, DSU, DTU, DTHU, DTH1U, DTH2U, DTBU, DTBVU, DTBCU,
DTFU, DTBLU, DSUSN, DSVUSN, DTPU, PSDRU, TDRU, TDSU, TASU,
TATU, TATBU
Assembly
In order to fulfil the requirements for air-tightness class D, the dampers must be installed as per ‘Assembly Instruction
Lindab Safe’.
For certain manual dampers, there is the option of adding a motor later on.
The dampers allow 50 mm duct insulation without the knob being hidden. For 100 mm duct insulation, there is an insu-
lation cup, IK, for DRU, DSU, DTU, TASU and TATU.
PSDRU, TDRU and TDSU
The dampers are installed by inserting the two guide pins on the T-piece or saddle into the L-shaped slots on the dam-
pers. The dampers are then locked by turning them slightly clockwise.
Balancing
On DRU, PSDRU and TDRU the damper blade is stepless adjustable through 0–90° (0°=fully open, 90°=completely
closed) using the knob in the cup. Locking is performed using screws for Pozidrive (PZD2) and the damper angle can be
read off a stamped grade on the edge of the cup. Other types of damper normally only work in the fully open or comple-
tely closed positions.
On motorized shut-off dampers and dampers adapted for a motor, the shaft end for the motor is equipped with a notch
showing the position of the damper blade.
Manual dampers Ø <355 can be supplemented with a sturdy handle to facilitate adjustment. Larger dimensions are
equipped with a handle as standard.
Maintenance
Dampers and motors normally don't require any maintenance.
CE marking
Our dampers with electrical actuator are regarded as a component in the duct system and does not need to be CE
marked separately.
Their electrical actuators on the other hand are part of the electrical system and are CE marked. Declaration of compli-
ance with the essential requirements can be found at www.belimo.ch .

5
We reserve the right to make changes without prior notice
lindab | we simplify construction
CM 24 / CM 24 F CM 230 / CM 230 F
Power supply............................. AC 19,2–28,8 V, 50/60 Hz AC 65–265 V, 50/60 Hz
DC 19,2–28,8 V
Power consumption .................. 0,5 W 1,5 W
For wire sizing ........................... 1 VA 3 VA
Connection ................................ Cable 1 m, 3×0,75 mm2 Cable 1 m, 3×0,75 mm2
Operating angle......................... Continously rotating Max. 95°, adjustable 0–100%
Torque at rated voltage.............. Min. 2 Nm Min. 2 Nm
Direction of rotation................... -L or -R -L or -R
Position indication..................... Mechanical, removable Mechanical, removable
Running time for 95° ................. 75 s 75 s
Sound power level..................... Max. 35 dB (A) Max. 35 dB (A)
Protection class......................... III Safety extra-low voltage II Safety insulated
Protection type .......................... IP 54 IP 54
Ambient temperature range ...... -30 to +50°C -30 to +50°C
Ambient moisture ...................... 95 % RF 95 % RF
–+
123
L
R
–+
12
0
3
L
R
Dampers
LM 24 A-F LM 230 A-F
Power supply............................. AC 19,2–28,8 V, 50/60 Hz AC 65–265 V, 50/60 Hz
DC 19,2–28,8 V
Power consumption .................. 1 W 1,5 W
For wire sizing ........................... 2 VA 4 VA
Connection ................................ Cable 1 m, 3×0,75 mm² Cable 1 m, 3×0,75 mm²
Operating angle......................... Max. 95°, adjustable 0–100% Max. 95°, adjustable 0–100%
Torque at rated voltage.............. Min. 5 Nm Min. 5 Nm
Direction of rotation................... Switch selectable Switch selectable
0 or 1 0 or 1
Position indication..................... Mechanical Mechanical
Running time for 95° ................. 150 s 150 s
Sound power level..................... Max. 35 dB (A) Max. 35 dB (A)
Protection class......................... III Safety extra-low voltage II Safety insulated
Protection type .......................... IP 54 IP 54
Ambient temperature range ...... -30 to +50°C -30 to +50°C
Ambient moisture ...................... 95 % RH 95 % RH
–+
123
0
1
–+
12
0
3
0
1
CM 24 SR
Power supply............................. AC 24 V, 50/60 Hz
DC 24 V
Power consumption .................. 0,5 W
For wire sizing ........................... 2 VA
Connection ................................ Cable 1 m, 4×0,75 mm²
Torque at rated voltage.............. Min. 2 Nm
Direction of rotation................... Switch selectable 0 or 1
Running time for 95° ................. 75 s
Sound power level..................... Max. 35 dB (A)
Protection class......................... III Safety extra-low voltage
Protection type .......................... IP 54
Ambient temperature range ...... -30 to +50°C
Ambient moisture ...................... 95 % RH
–+
1235
U
Y DC 0–10
V
DC 2–10
V

6
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Dampers
LM 24 A-SR LM 230 A-SR
Power supply............................. AC 19,2–28,8 V, 50/60 Hz AC 230 V, 50/60 Hz
DC 19,2–28,8 V
Power consumption .................. 1 W 1,8 W
For wire sizing ........................... 2 VA 4 VA
Connection ................................ Cable 1 m, 4×0,75 mm² Cable 1 m, 2×0,75 mm²
Operating angle......................... Max. 95°, adjustable Max. 95°, adjustable
Torque at rated voltage.............. Min. 5 Nm Min. 5 Nm
Direction of rotation................... Switch selectable Switch selectable
0 or 1 0 or 1
Position indication..................... Mechanical Mechanical
Running time for 95° ................. 150 s 150 s
Sound power level..................... 35 dB (A) 35 dB (A)
Protection class......................... III Safety extra-low voltage II
Protection type .......................... IP 54 IP 54
Ambient temperature range ...... -30 to +50°C -30 to +50°C
Ambient moisture ...................... 95 % RH 95 % RH
–+
1235
U
Y DC 0–10 V
DC 2–10 V
LMQ 24A LMQ-SR 24A
Power supply............................. AC 19,2-28,8 V, 50/60 Hz AC 19,2-28,8 V, 50/60 Hz
................................................... DC 21,6-28,8 V DC 21,6-28,8 V
Power consumption .................. 13 W 12 W
For wire sizing ........................... 23 VA 23 VA
Connection ................................ Cable 1 m, 3×0,75 mm² Cable 1 m, 4×0,75 mm²
Operating angle......................... Max. 95°, adjustable 0-100 % Max. 95°, adjustable 0-100 %
Torque at rated voltage.............. Min. 4 Nm Min. 4 Nm
Direction of rotation................... Switch selectable Switch selectable
0 or 1 0 or 1
Position indication..................... Mechanical Mechanical
Running time for 90° ................. 2,5 s 2,5 s
Sound power level..................... 52 dB (A) 52 dB (A)
Protection class......................... III Safety extra-low voltage II Safety insulated
Protection type .......................... IP 54 IP 54
Ambient temperature range ...... -30 to +40°C -30 to +40°C
Ambient moisture ...................... 95 % RH 95 % RH
–+
123
0
1
–+
1235
U
Y DC 0–10
V
DC 2–10
V
LM 24 A-SX
Power supply............................. AC 19,2–28,8 V, 50/60 Hz
DC 21,6–28,8 V .........................
Power consumption .................. 2 W
For wire sizing ........................... 4 VA
Connection ................................ Cable 1 m, 4×0,75 mm2
Operating angle......................... Max. 95°, adjustable 0–100 %
Torque at nominal voltage ......... Min. 5 Nm
Direction of rotation................... Switch selectable 0/1
Position at Y=0 V....................... Switch selectable 0 or 1
Position indication..................... Mechanical
Running time for 90° ................. 150 s
Sound power level..................... 35 dB (A)
Protection class......................... III Safety extra-low voltage
Protection type .......................... IP 54
Ambient temperature range ...... -30 to +50 °C
Ambient humidity ...................... 95 % RH
–+
1235
U
YD
C 0–10
V
DC 2–10
V

7
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Dampers
–+
123
0
1
–+
12
0
3
0
1
NM 24 A-F NM 230 A-F
Power supply............................. AC 19,2–28,8 V, 50/60 Hz AC 85–265 V, 50/60 Hz
DC 19,2–28,8 V
Power consumption .................. 1,5 W 2,5 W
For wire sizing ........................... 3,5 VA 6 VA
Connection ................................ Cable 1 m, 3×0,75 mm2 Cable 1 m, 3×0,75 mm2
Operating angle......................... Max. 95°, adjustable 0–100% Max. 95°, adjustable 0–100 %
Torque at rated voltage.............. Min. 10 Nm Min. 10 Nm
Direction of rotation................... Switch selectable Switch selectable
0 or 1 0 or 1
Position indication..................... Mechanical Mechanical
Running time for 95° ................. 150 s 150 s
Sound power level..................... Max. 35 dB (A) Max. 35 dB (A)
Protection class......................... III Safety extra-low voltage II Safety insulated
Protection type .......................... IP 54 IP 54
Ambient temperature range ...... -30 to +50°C -30 to +50°C
Ambient moisture ...................... 95 % RH 95 % RH
–+
123
0
1
–+
12
0
3
0
1
SM 24 A SM 230 A
Power supply............................. AC 19,2–28,8 V, 50/60 Hz AC 85–265 V, 50/60 Hz
DC 19,2–28,8 V
Power consumption .................. 2 W 2,5 W
For wire sizing ........................... 4 VA 6 VA
Connection ................................ Cable 1 m, 3×0,75 mm2 Cable 1 m, 3×0,75 mm2
Operating angle......................... Max. 95°, adjustable 0–100% Max. 95°, adjustable 0–100%
Torque at rated voltage.............. Min. 20 Nm Min. 20 Nm
Direction of rotation................... Switch selectable Switch selectable
0 or 1 0 or 1
Position indication..................... Mechanical Mechanical
Running time for 95° ................. 150 s 150 s
Sound power level..................... Max. 35 dB (A) Max. 35 dB (A)
Protection class......................... III Safety extra-low voltage II Safety insulated
Protection type .......................... IP 54 IP 54
Ambient temperature range ...... -30 to +50°C -30 to +50°C
Ambient moisture ...................... 95 % RH 95 % RH
GM 24 A GM 230 A
Power supply............................. AC 19,2–28,8 V, 50/60 Hz AC 85–265 V, 50/60 Hz
DC 19,2–28,8 V
Power consumption .................. 4,5 W 4,5 W
For wire sizing ........................... 7 VA 7 VA
Connection ................................ Cable 1 m, 3×0,75 mm2 Cable 1 m, 3×0,75 mm2
Operating angle......................... Max. 95°, adjustable 0–100% Max. 95°, adjustable 0–100%
Torque at rated voltage.............. Min. 40 Nm Min. 40 Nm
Direction of rotation................... Switch selectable Switch selectable
0 or 1 0 or 1
Position indication..................... Mechanical Mechanical
Running time for 95° ................. 150 s 150 s
Sound power level..................... Max. 45 dB (A) Max. 45 dB (A)
Protection class......................... III Safety extra-low voltage II Safety insulated
Protection type .......................... IP 54 IP 54
Ambient temperature range ...... -30 to +50°C -30 to +50°C
Ambient moisture ...................... 95 % RH 95 % RH
–+
123
0
1
–+
12
0
3
0
1

8
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Dampers
TF 24 TF 230
Power supply............................. 2AC 19,2–28,8 V, 50/60 Hz AC 85–265 V, 50/60 Hz
DC 21,6–28,8 V
Power consumption
– during opening........................ 2,5 W 2,5 W
– stand-by ................................. 1,5 W 1,5 W
For wire sizing ........................... 5 VA 5 VA
Connection ................................ Cable 1 m, 2×0,75 mm² Cable 1 m, 2×0,75 mm²
Operating angle, adjustable ...... Mech. limited to 95° Mech. limited to 95°
Torque at rated voltage
– motor ...................................... Min. 2 Nm Min. 2 Nm
– return spring ........................... Min. 2 Nm Min. 2 Nm
Direction of rotation................... Optional through right or Optional through right or
left-hand installation L/R ........... left-hand installation L/R
Position indication..................... Mechanical Mechanical
Running time
– motor ...................................... < 75 s (0–2 Nm) < 75 s (0–2 Nm)
– return spring ........................... < 25 s < 25 s
Degree of protection.................. IP 42 IP 42
Ambient temperature range ...... -30 to +50°C -30 to +50°C
1
NL1
2
M
LF 24 LF 230
Power supply............................. 2AC 19,2–28,8 V, 50/60 Hz AC 198–264 V, 50/60 Hz
DC 21,6–28,8 V
Power consumption
– during opening........................ 5 W 5 W
– stand-by ................................. 2,5 W 3 W
For wire sizing ........................... 7 VA 7 VA
Connection ................................ Cable 1 m, 2×0,75 mm² Cable 1 m, 2×0,75 mm²
Operating angle, adjustable ...... Mech. limited to 95° Mech. limited to 95°
Torque at rated voltage
– motor ...................................... Min. 4 Nm Min. 4 Nm
– return spring ........................... Min. 4 Nm Min. 4 Nm
Direction of rotation................... Optional through right or Optional through right or
left-hand installation L/R left-hand installation L/R
Position indication..................... Mechanical Mechanical
Running time
– motor ...................................... 40–75 s (0–4 Nm) 40–75 s (0–4 Nm)
– return spring ........................... app. 20 s app. 20 s
Sound power level
– motor ...................................... max 50 dB (A) max 50 dB (A)
– return spring ........................... app. 62 dB (A) app. 62 dB (A)
Degree of protection.................. IP 54 IP 54
Ambient temperature range ...... -30 to +50°C -30 to +50°C
1
NL1
2
M

9
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SFA (both 24 V and 230 V power supplay)
Power supply............................. AC 19,2–28,8 V, 50/60 Hz
DC 21,6–137,5 V
Power consumption
– during operation ..................... 7 W
– stand-by ................................. 3,5 W
For wire sizing ........................... 18 VA (Imax 20 A @ 5 ms)
Connection ................................ Cable 1 m, 2×0,75 mm2
Operating angle, adjustable ...... Mech. limited to 95°
Torque at rated voltage
– motor ...................................... Min. 20 Nm
– spring bias .............................. Min. 20 Nm
Direction of rotation................... Optional through right or left-hand installation L/R
Position indication..................... Mechanical
Running time
– motor ...................................... ≤ 75 s (0 … 20 Nm)
– return spring ........................... ≤ 20 s @ -20 … 50°C / max. 60 s @ -30°C
Sound power level
– motor ...................................... ≤ 45 dB (A)
– return spring ........................... ≤ 62 dB (A)
Degree of protection.................. IP 54
Ambient temperature range ...... -30 to +50 °C
Ambient temperature range ...... -30 to +50 °C
1
NL
2
M
EF 24A EF 230A
Power supply............................. AC 19,2–28,8 V, 50/60 Hz AC 90–264 V, 50/60 Hz
DC 21,6–28,8 V
Power consumption
– during operation ..................... 9,5 W 9 W
– stand-by ................................. 4,5 W 4,5 W
For wire sizing ........................... 16 VA 21 VA
Connection ................................ Cable 1 m, 2×0,75 mm2 Cable 1 m, 2×0,75 mm2
Operating angle, adjustable ...... Mech. limited to 95° Mech. limited to 95°
Torque at rated voltage
– motor ...................................... Min. 30 Nm Min. 30 Nm
– spring bias .............................. Min. 30 Nm Min. 30 Nm
Direction of rotation................... Optional through right or Optional through right or
left-hand installation L/R left-hand installation L/R
Position indication..................... Mechanical Mechanical
Running time
– motor ...................................... ≤75 s (0–30 Nm) ≤75 s (0–30 Nm)
– return spring ........................... ≤20 s ≤20 s
Sound power level
– motor ...................................... ≤55 dB (A) ≤55 dB (A)
– return spring ........................... ≤71dB (A) ≤71dB (A)
Degree of protection.................. IP 54 IP 54
Ambient temperature range ...... -30 to +50 °C -30 to +50 °C
1
NL
2
M
Dampers

10
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Assembly
In order to fulfil the requirements for air-tightness class C, the damper must be installed as per ‘Assembly Instruction
Rectangular air duct systems’.
For the damper, there is the option of adding a motor later on.
The damper allows a 50 mm duct insulation without the knob being hidden. For 100 mm insulation, an insulation cup,
IK, is available.
Balancing
On LKSR the damper blade is adjusted through 0–90° (0° = fully open, 90° = completely closed) using the knob in the
cup. Locking is performed using screws for Pozidrive (PZD2) and the damper angle can be read off a stamped grade on
the edge of the cup.
Manual damper can be supplemented with a sturdy handle to facilitate adjustment.
Maintenance
The damper and motor normally don't require any maintenance.
Dampers
LKSR

11
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Constant/variable flow dampers
DAU, DA2EU, DAVU
Assembly
In order to fulfil the requirements for air-tightness class D, the devices must be installed as per ‘Assembly Instruction
Lindab Safe’.
The devices must be installed with the air flow in the direction of the arrow.
The devices allow 50 mm duct insulation without the scale or any motor being hidden.
Pressure range
50–1000 Pa over the unit.
Interference sensitivity
In order to achieve stated precision for the set flow, a straight duct of at least 3×d before and 1.5×d after the devices is
required. A assembly close to a source of interference (bend, saddle, etc.) reduces control accuracy and the flow can
deviate from the set value.
Changes in direction
The units are independent of their direction of installation; you can deviate from the projected direction and install them
in any direction you like without affecting accuracy.
Systematic error
Control accuracy
The devices are calibrated within their entire operating range at the factory. This means the devices keep the flow con-
stant to within approx. ±5 to ±10 % of the set flow. Larger deviations occur at lower flows, especially with small sizes.
Maintenance
The devices normally don't require any maintenance, but should be protected from contaminated air wherever possible.
CE marking
Our dampers with electrical actuator are regarded as a component in the duct system and does not need to be CE
marked separately.
Their electrical actuators on the other hand are part of the electrical system and are CE marked. Declaration of compli-
ance with the essential requirements can be found at www.belimo.ch .

12
We reserve the right to make changes without prior notice
lindab | we simplify construction
Technical data for the motors
LM 24 A LM 230 A
Power supply............................. AC 19,2–28,8 V, 50/60 Hz AC 65–265 V, 50/60 Hz
DC 19,2–28,8 V
Power consumption .................. 1 W 1,5 W
For wire sizing ........................... 2 VA 4 VA
Connection ................................ Cable 1 m, 3×0,75 mm2 Cable 1 m, 3×0,75 mm2
Operating angle......................... Max. 95°, adjustable 0–100% Max. 95°, adjustable 0–100%
Torque at rated voltage.............. Min. 5 Nm Min. 5 Nm
Direction of rotation................... Switch selectable Switch selectable
0 or 1 0 or 1
Position indication..................... Mechanical Mechanical
Running time for 95° ................. 150 s 150 s
Sound power level..................... Max. 35 dB (A) Max. 35 dB (A)
Protection class......................... III Safety extra-low voltage II Safety insulated
Protection type .......................... IP 54 IP 54
Ambient temperature range ...... -30 to +50°C -30 to +50°C
Ambient moisture ...................... 95 % RH 95 % RH
–+
123
0
1
–+
12
0
3
0
1
DA2EU
Setting of flows
The two flows are set by moving the end stops. At delivery the stops are set at largest
possible distance. If you want to limit the flow span proceed in the following way:
1. The one flow is set by turning the spindle so that the scale arrow points at the
desired flow and thereafter move one of the end stops close up to the clamp's one
heel and lock the stop there.
2. The other flow is set by turning the spindle so that the scale arrow points at this flow
and thereafter move the other end stop close up to the clamp's other heel and lock
this stop there.
Choice of flows
The one flow is chosen by feeding an operating voltage. This voltage, 24 or 230 V, turns
the motor to one of the stops.
The other flow is chosen by breaking the operating voltage. The motor then goes to the
other stop.
BELIMO R
End stop screws
Made in Switzerland
LM230A
0
1
Constant/variable flow dampers
DAU
The flow is adjusted by loosening the central nut and using the knob to turn the scale
arrow so that it points to the desired flow on the scale. The nut is then locked.
Scale arrow
Center nut

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Constant/variable flow dampers
DAVU
Setting of flow limits
The two flow limits are set by moving the end stops. At delivery the stops are set at lar-
gest possible distance. If you want to limit the flow span proceed in the following way:
1. The one flow limit is set by turning the spindle so that the scale arrow points at the
desired flow and thereafter move one of the end stops close up to the clamp's one
heel and lock the stop there.
2. The other flow limit is set by turning the spindle so that the scale arrow points at this
flow and thereafter move the other end stop close up to the clamp's other heel and
lock this stop there.
3. The motor shall then be adapted so that the regulating span 2–10 V adapts to the
thus set flow span. This is done by a push on the "gear disengagement" button. The
motor then automatically performs a stroke between the flow limits.
Choice of flow
The flow is chosen by feeding a control signal. This signal, 2–10 V, sets the motor in a
proportional position between the flow limits.
BELIMO R
Made in Switzerland
LM24 A-SX
0
1
End stop scr
ews
Technical data for the motor
LM 24 A-SX
Power supply............................. AC 19,2–28,8 V, 50/60 Hz
DC 21,6–28,8 V
Power consumption .................. 2 W
For wire sizing ........................... 4 VA
Connection ................................ Cable 1 m, 4×0,75 mm²
Operating angle......................... Max. 95°, adjustable 0–100 %
Torque at nominal voltage ......... Min. 5 Nm
Direction of rotation................... Switch selectable 0/1
Position at Y=0 V....................... Switch selectable 0 or 1
Position indication..................... Mechanical
Running time for 90° ................. 150 s
Sound power level..................... 35 dB (A)
Protection class......................... III Safety extra-low voltage
Protection type .......................... IP 54
Ambient temperature range ...... -30 to +50 °C
Ambient humidity ...................... 95 % RH
–+
1235
U
YDC 0–10
V
DC 2–10
V

14
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Air stream operated dampers
CARU, CAR
Assembly
CARU
In order to fulfil the requirements of tightness class D the damper must be installed as per ‘Assembly Instruction Lindab
Safe’.
CAR
The damper is installed by simply placing it inside a duct.
Measurement
The dampers normally don’t need any maintenance.

15
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Measuring bends
MBU, MBFU
Assembly
In order to fulfil the requirements for air-tightness class D, the bends must be installed as per ‘Assembly Instruction
Lindab Safe’.
The bends allow 50 mm duct insulation without the measuring points being hidden. For 100 mm insulation, an insulation
cup, IK, is available.
Measurement
By measuring the pressure difference ∆p in Pa at the measuring points, you can achieve a flow q in l/s using the equa-
tion on the devices.
The specified flows only apply for air with a density of 1.2 kg/m3. For air of another density (rother) the flow (qother_density)
is achieved as per the formula:
qother_density = qequation × ρ
other
1,2
Device Dimension
mm k-factor
MBU
100 6.85
125 10.3
160 17.0
200 26.3
250 41.7
MBFU
315 65.0
400 115
500 179
630 283
Systematic error
Straight stretches are required in order to achieve flows as per equations with specified accuracy. The systematic error
m2is 5% and 10% below the minimum requirements for straight stretches as specified.
Maintenance
The measuring bends normally don't require any maintenance.
Cleaning
The device does not limit cleaning opportunities.

16
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Assembly
In order to fulfil the requirements for air-tightness class D, the devices must be installed as per ‘Assembly Instruction
Lindab Safe’.
FMDRU must be installed with the air flow in the direction of the arrow.
The devices allow 100 mm duct insulation without sticker or measuring points being hidden. The cup around FMDRU’s
damper knob allows 50 mm duct insulation without the knob being hidden. For 100 mm insulation, an insulation cup, IK,
is available.
For optimum readability (regardless of the installation position), the plate with the sticker can be turned, folded up to
prevent it disappearing in any insulation or to be easily removed and positioned separately from the device.
Measurement
By measuring the pressure difference ∆p in Pa at the measuring points, you can achieve a flow q in l/s using the equa-
tion on the devices.
With FMDRU you can set the desired flow, as the damper blade is adjustable through 0–90° (0°=fully open, 90°=com-
pletely closed) using the knob in the cup. Locking is performed using screws for Pozidrive (PZD2) and the damper angle
can be read off a stamped grade on the edge of the cup.
The specified flows only apply for air with a density of 1.2 kg/m3. For air of another density (rother) the flow (qother_density)
is achieved as per the formula:
qother_density = qequation × ρ
other
1,2
Dimension
mm
k-factor
80– 63 4,40
100– 80 7,32
125–100 11,2
160–125 18,0
200–160 29,4
250–200 45,7
315 –250 73,3
400–315 116
500–400 191
630–500 283
Systematic error
Straight stretches are required in order to achieve flows as per equations with specified accuracy. The systematic error
m2is 5% and 10% below the minimum requirements for straight stretches as specified. For these minimum straight
requirements – do not install measuring points in line with the nearest bend’s inside radius.
Maintenance
The devices normally don't require any maintenance.
Cleaning
FMU does not limit cleaning opportunities.
Flow meters
FMU, FMDRU

17
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Assembly
In order to fulfil the requirements for air-tightness class D, the device must be installed as per ‘Assembly Instruction
Lindab Safe’.
The device must be installed with the air flow in the direction of the arrow.
The device allows 50 mm duct insulation without sticker or measuring points being hidden.
The cup around the damper knob allows 50 mm duct insulation without the knob being hidden. For 100 mm insulation,
an insulation cup, IK, is available.
For optimum readability (regardless of the installation position), the plate with the sticker can be turned or easily remo-
ved and positioned separately from the device.
Measurement
By measuring the pressure difference ∆p in Pa at the measuring points, you can achieve a flow q in l/s using the equa-
tion on the device.
You can set the desired flow, as the damper blade is adjustable through 0–90° (0°=fully open, 90°=completely closed)
using the knob in the cup. Locking is performed using screws for Pozidrive (PZD2) and the damper angle can be read
off a stamped grade on the edge of the cup.
The specified flows only apply for air with a density of 1.2 kg/m3. For air of another density (rother) the flow
(qother_density) is achieved as per the formula:
qother_density = qequation × ρ
other
1,2
Dimension
mm k-factor
Colour coding
for measuring
points
80 2.99 transparent
100 4.90 red
125 7.9 5 green
160 13.8 yellow
200 21.3 blue
250 34.6 black
315 57. 8 white
400 88.8 transparent
500 146 red
630 234 green
Systematic error
Straight stretches are required in order to achieve flows as per equations with specified accuracy. The systematic error
m2is 5% and 10% below the minimum requirements for straight stretches as specified.
Maintenance
The device normally doesn't requires any maintenance.
Flow meters
FMDU

18
We reserve the right to make changes without prior notice
lindab | we simplify construction
Assembly
Mount the dampers according to “Assembly Instructions Lindab Safe” to meet with the requirements for tightness class
C.
Consider required straight distance after or before disturbance, as mentioned on the card attached to the measurement
nozzles, to obtain accurate flow measurement. Dampers with dimension 400, 500 and 630 are provided with transport
protections. Remove these before assembly.
The damper may not be loaded with weight from connected ducts, specially when assembled vertically.
Measuring
Measurement accuracy
Consider required straight distance after or before disturbance, as mentioned on the card attached to the measurement
nozzles, to obtain accurate flow measurement.
Balancing
Connect the measuring hoses to the damper measuring nozzles.
Loosen the locking screws (3), which have Philips slot no.1. adjust the handle so that requisited pressure drop recei-
ves. Fasten the screws (3) and remount the tightness screws (2), so that the slot gets airtight.
For dimension 400,500 and 630 - remove the tightness screws (2). Then loosen the locking screws (3), which have
Philips slot no. 2. Adjust the handle so that requisited pressure drop receives. Fasten the screws (3) and remount the
tightness screws (2), so that the slot gets airtight.
Disconnect the hoses and plug the nozzles.
Maintenance
The product normally doesn't requires any maintenance.
Cleaning
By fully open the damper, one get access to the duct. Do not forget to readjust the damper after cleaning.
The balancing graphs show the flow, q, as a function of the measured pressure, ∆pm, in the measure nozzles.
q=k · ∆p
m
The formula is only accurate for air with the density 1,2 kg/m³. For air with other density, (rother), the flow, (qother), is
given according to the formula.
q
other= qequation × ρ
other
1,2
The balancing graphs should only be used to balance the system. They should not be used to calculate the pressure
drop in the system, in those cases the dimensioning graphs should be used.
Measuring pressure ∆pm
Damper with flow meter
DIRU

19
We reserve the right to make changes without prior notice
lindab | we simplify construction
To set the air flow:
1. Determine the k factor on the scale on the damper, k.
2. Measure the pressure difference by connecting a measuring device to the damper’s nozzles, ∆pm.
3. Calculate the flow by using the formula,
q=k · ∆p
m.
4. Compare the calculated flow to the required.
5. Adjust the damper if necessary and repeat steps 1-4 until you get the required flow.
Don’t forget to plug the nozzles after measuring.
Damper with flow meter
DIRU, DIRBU, DIRVU
2
2
3
3
1

20
We reserve the right to make changes without prior notice
lindab | we simplify construction
15 20 30 40 50 100
q
10
20
30
40
50
100
200
300
∆p
m
k
[m/s]
[l/s]
[Pa]
2345 10
v
1,5
2,0
2,5
3,0
3,5
4,0
4,5
5,0
5,5
6,0
Ø100
20
30
50
100
200
300
500
[Pa]
∆p
t
Ø100
10
820304050 120100 [l/s]
[m/s]
q
v
k
123451015
1,5 2,0 2,5 3,0 3,5 4,0
4,5
5,0
5,5
6,0
40
45
50
55
60
65
70
75
85
80
L
WA
[dB]
25 30 40 50 100 150
q
10
20
30
40
50
100
200
300
∆p
m
k
[m/s]
[l/s]
[Pa]
34510
v
1,5
2,0
3,0
4,0
5,0
6,0
7,0
8,0
9,0
10
Ø125
20
30
50
100
200
300
500
[Pa]
∆p
t
Ø125
15
12 20 30 40 50 180100 [l/s]
[m/s]
q
v
k
123451015
1,5 2,0 3,0 4,0 5,0
6,0
7,0
8,0
9,0
10,0
40
35
45
50
55
60
65
70
LWA [dB]
q
1510 20 30 40 50 60
10
20
30
40
50
100
200
300
v
11109876
5432
[Pa]
[l/s]
[m/s]
∆p
m
k
Ø80
1,5
1,0
2,0
2,5
3,0
3,5
4,0
20
30
50
100
200
300
500
[Pa]
∆p
t
Ø80
10
52030405075[l/s]
[m/s]
q
v
k
123451015
1,51,0 2,0 2,5
3,0
3,5
4,0
40
35
45
50
55
60
65
70
75
80
85 90
LWA [dB]
Flow graphs for balancing
The balancing graphs show the flow as a function of the
measured pressure, ∆pm. These graphs should be used
to balance the system.
Pressure drop graphs with noise genera-
tion for dimensioning
The dimensioning graphs show the pressure drop over
the damper with flow meter, ∆pt. They should be used to
determine the pressure drop and to provide information
about sound power levels at different settings.
Damper with flow meter
DIRU, DIRBU, DIRVU