background image

INSTRUCTION

 

TVAN

i

Read this instruction before  

installation and wiring of the product.

Consult documentation in all cases where this symbol 

is used, in order to find out the nature of the potential 

hazards and any actions to be taken

1

TVAN

Drill a <Ø16 mm hole in the duct wall. For optimal measuring results, 
measuring points with turbulent air flow should be avoided. Preferably, 
measuring should be performed at a distance of 2 duct diameters before 
bends and branching and at 6 duct diameters after bends and branching.
 

<16 mm

60 mm

Air velocity

Hold the flange against the hole and drill fastening holes using the flange 

as template. Fasten the flange.

Mount the sensor stem through the hole in the flange and fix it at desired 
depth.

Immersion length

30 - 50 % of pipe diameter 

Air velocity

INCORRECT

CORRECT

It is also possible to mount the sensor using the screw-pockets in the 
sensor housing.

In both cases it is essential to position the sensor so that there can be an 
unobstructed, straight airflow past the sensor element.

Wiring

Connect supply voltage and output signal according to the diagram 
below.

t90 HI MED LO I U

t90 HI MED LO I U

t90 HI MED LO I U

t90 HI MED LO I U

t90 HI MED LO I U

t90 HI MED LO I U

t90 HI MED LO I U

Output

Working range

Response time

No jumper

Jumper

Jumper

Jumper

Jumper

FAST 

approx. 0.7 s

Jumper

Current (I)

Jumper

Voltage (U)
= factory setting

= factory setting

= factory setting

0...10 m/s

0...15 m/s

0...20 m/s

SLOW  approx. 4 s

The output signal, working range and response time are selected by 
the jumpers according to the picture above.

The response time is normally set to 4 seconds. By removing the 
jumper it is shortened to 0.7 seconds.

Maintenance

Should the element become very dirty it can be blown clean using a 

soft air-jet or be rinsed in isopropyl alcohol.

12807A

 

DEC 16

EN

1     Supply voltage 24 V AC   
2     System neutral
3     0...10 V or 4...20 mA

Duct mounted air velocity transmitter

TVAN is a duct mounted air velocity transmitter for measuring air 
velocity in air handling systems.The air velocity sensor operates on 
the hot-wire anemometer principle. 

The output can be set to 0...10 V or 4...20 mA.
Different measuring ranges for full output signal can be set to give the 
best possible accuracy.

There is a choice of two different response times for the output signal.

Installation

 

It is important that the unit is mounted so that the direction of the 
sensor head opening corresponds to the direction of the air flow (an 
arrow indicating the flow direction is shown inside the housing).

Air velocity

Air velocity

Correct

Incorrect 

Reviews: