The air velocity transmitter AVT is intended for air velocity measurement
inside the ventilation duct in HVAC systems.
Air velocity transmitter AVT 251 types have selectable ranges
0-5 m/s, 0-10 m/s, 0-15 m/s or 0-20 m/s.
Air velocity transmitter AVT 551 types have selectable ranges
0-1 m/s, 0-2 m/s, 0-3 m/s or 0-5 m/s.
The air velocity transmitter AVT 251 and AVT 551 have two outputs for Air Velocity
4-20 mA and 0-10 Vdc.
The air velocity accuracy for air velocity transmitter AVT is ±5 % for 0-20 m/s.
The temperature accuracy for air velocity transmitter AVT is 0.5°C at min 1 m/s.
Power supply for air velocity transmitter AVT is 24 Vac/dc.
Response time for air velocity transmitter AVT is 1 second or 5 seconds,
DIP switches selectable
The sensors for the air velocity transmitter AVT is located in the end of the probe
to measure air velocity and temperature inside the duct.
Air velocity transmitter AVT have IP65 enclosure and IP10 for the probe.
The air velocity transmitter AVT have 1 screw and 2 snap lids in the cover of the enclosure.
Wiring connection for the air velocity transmitter AVT is inside the plastic enclosure on a terminal block.
The enclosure of the air velocity transmitter AVT is supplied with a plastic cable entry gland.
The probe for the air velocity transmitter AVT is made of plastic.
The air velocity transmitter AVT is supplied with a duct mounting flange for
fast and easy mounting.
The duct mounting flange have neoprene gasket for good sealing into the duct.
Pentration depth of probe can be adjusted with the duct mounting flange.
More features for air velocity transmitters AVT 251 MDR2B and AVT 551 MDR2B
• Modbus RS485 communication
• LCD Display
• 2 x relay outputs
• Buzzer
On request:
• Output 2-10 Vdc, 0-5 Vdc and 1-5 Vdc
• Output number 2 (AO2) can be supplied as
Temperature output instead of Air Velocity output.
• Other combination AVT types in data sheet to down load below
Ordering examples
AVT 251
Air Velocity transmitter
Ranges 0-5 m/s, 0-10 m/s, 0-15 m/s or 0-20 m/s, DIP switches selectable
Output 1 (AO1) : 4-20 mA
Output 2 (AO2) : 0-10 Vdc
AVT 551
Air Velocity transmitter
Ranges 0-1 m/s, 0-2 m/s, 0-3 m/s or 0-5 m/s, DIP switches selectable
Output 1 (AO1) : 4-20 mA
Output 2 (AO2) : 0-10 Vdc
AVT 251 MDR2B
Air Velocity transmitter
Ranges 0-5 m/s, 0-10 m/s, 0-15 m/s or 0-20 m/s, DIP switches selectable
Output 1 (AO1) : 4-20 mA
Output 2 (AO2) : 0-10 Vdc
Modbus RS485 communication
LCD Display
2 x Relay outputs
Buzzer
AVT 551 MDR2B
Air Velocity transmitter
Ranges 0-1 m/s, 0-2 m/s, 0-3 m/s or 0-5 m/s, DIP switches selectable
Output 1 (AO1) : 4-20 mA
Output 2 (AO2) : 0-10 Vdc
Modbus RS485 communication
LCD Display
2 x Relay outputs
Buzzer