Room pressure control static transducer

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Universal device for use with VAV terminal units
  • Controller and static differential pressure transducer are fitted together in one casing
  • Separate actuator with simple plug connection
  • Use in ventilation and air conditioning systems, with clean and contaminated air
  • Room pressure control -10 to -50 Pa or +10 to +50 Pa
  • Constant value control Δpmin or variable control Δpmin – Δpmax
  • Operating parameters Δpmin and Δpmax are set in the factory and saved in the controller
  • Activation of override controls via external wiring
  • Modification of operating parameters by PC software as well as the smartphone and tablet app (TROX FlowCheck app)
  • Service access for PC configuration software
  • Smartphone access via NFC interface and Bluetooth
  • Setpoint value settings, override controls and parameter adjustment via analogue interface or bus communication
  • High data transparency through standardised bus communication Modbus RTU, BACnet MS/TP or MP bus

General information


  • All-in-one control engineering device for VAV terminal units for room pressure control in ventilation and air conditioning systems with non-critical (sufficient) room leakage
  • Control range: negative pressure range -10 to -50 Pa or positive pressure range +10 to +50 Pa
  • Switchover of setpoint setting between positive and negative pressure by means of Modbus-/BACnet network data points
  • Static differential pressure transducer and controller electronics combined in one casing
  • Separate actuator with prefabricated connection plug
  • For use with clean and contaminated air
  • Variable room pressure control by specifying setpoint values via communication interfaces or analogue signal e.g. from the central building management system
  • Room pressure control with constant value by set operating value
  • Override controls for activating Δpmax, Δpmin, shut-off, control stop, OPEN position via Modbus/BACnet register or partly with switch or relay possible
  • Room pressure actual value is available as a network data point or linear voltage signal
  • Damper blade position is available as a network data point
  • Use the TROX FlowCheck app and PC tool to configure the controller and the communication parameters

Control strategy
  • Room pressure control for positive or negative pressure operation
  • Nominal pressure ΔpNom:
  • At positive pressure: ΔpNom = 75 Pa
  • At negative pressure: ΔpNom = -75 Pa
  • Reference point for the output signal: ΔpNom
  • Room pressure fluctuations are controlled, e.g. by changing volume flow requirements
  • To prevent the control from becoming unstable, a dead band is allowed within which the damper blade does not move
  • Δpmin: selected operating value of minimum room pressure or constant value
  • Δpmax: selected operating value of maximum room pressure Operating parameters are specified via the order code and set in the factory

Analogue interface
  • Analogue interface with adjustable signal voltage range
  • Analogue signal for pressure setpoint value
  • Analogue signal for actual pressure value
Digital communication interface (Bus)
  • Modbus RTU, RS485
  • BACnet MS/TP, RS485
  • MP bus
  • Data points, see bus lists
Hybrid mode
  • Mixed mode of analogue and digital interface
Factory setting
  • Setpoint value setting via analogue interface
  • Actual value output via analogue interface and Modbus communication interface

Operating modes
Variable operation (V)
  • Setpoint value setting via analogue signal, Modbus, BACnet or MP-Bus: operating range corresponds to Δpmin – Δpmax
Constant value mode (F)
  • A setpoint signal is not required, setpoint value corresponds to Δpmin

Operating parameters
Recommended control range, factory-set so that adjustment behaviour is fully visible in the output signal:
  • At positive pressure: Δpmin = 10 Pa – 50 Pa, Δpmax = 15 Pa – 50 Pa
  • At negative pressure: Δpmin = -10 Pa – -50 Pa, Δpmax = -15 Pa – -50 Pa
Possible setting range, adjustable by others:
  • At positive pressure: Δpmin = 0 Pa – 75 Pa, Δpmax = 15 Pa – 75 Pa
  • At negative pressure: Δpmin = 0 Pa – -75 Pa, Δpmax = -15 Pa – -75 Pa

Signal voltage ranges
  • 0 – 10 V DC
  • 2 – 10 V DC

Parts and characteristics
  • Transducer for static measurement principle
  • Separate drive, overload-proof
  • Plug-in terminals for supply line and controls including cover
  • Socket for the actuator
  • NFC and service interface
  • Release button to allow for manual operation
  • Indicator lights for displaying the operating mode
  • Addressing key for setting user addresses in bus mode
  • Controller casing prepared with 4 openings for threaded connections, 2 cable glands M16 x 1.5 for connecting cable in the supply package
  • Controller casing can be opened without tools

BURN with actuator LM24A-VST for:
  • TVR, TZ-Silenzio, TA-Silenzio, TVZ, TVA,
  • TVRK up to nominal size 250
BURN with actuator NM24A-VST for:
  • TVJ
  • TVT up to dimension 1000 × 300 or 800 × 400
  • TVRK nominal size 315 - 400
BURN with actuator SM24A-VST for:
  • TVT from dimensions of 800 × 500 to 1000 × 600

  • Due to the room pressure operating values set at the factory, it must always be ensured that the control units are only installed at the intended locations
  • Modbus/BACnet/MP bus interface: additional commissioning steps required
  • Operating parameters can be adjusted using the TROX FlowCheck app

Useful additions
  • Smartphone app for Android and iOS
  • Adjustment device type ZTH-EU (order code AT-VAV-B)
  • Belimo PC-Tool
  • NFC Bluetooth converter ZIP-BT-NF

Technical information

Principle of operation Universal controller for room pressure control: TVR, TVJ, TVT, TZ-/TA-Silenzio, TVZ, TVA, TVRK BUPN_gc_01ai.png
① Differential pressure transducer
② Actuator
③ Differential pressure controller
④ Setpoint value signal or constant value
⑤ Differential pressure sensor of the VAV terminal unit
(unused, depending on type and variant possibly not accessible or not available)
⑥ Differential pressure connection at the transducer of the control component:
  • Use plus connection side for room pressure measuring point
  • Use the minus connection side for the constant pressure reference measurement point

Application area room pressure controller
Modern industrial production facilities with clean room
requirements or (laboratory) rooms in research and development often require precise room pressure control, especially since these rooms are often designed to be quite air-tight.
The aim here is to meet the specified ventilation requirements with regard to maintaining defined positive pressure or negative pressure conditions. A simple volume flow control is not sufficient for this. A room pressure controller with permanent pressure measurement and pressure control by adjusting the throttle position on the controller is required.

Function of a room pressure controller
A static differential pressure transducer converts the room
pressure into a voltage signal. The differential pressure actual
value is available as a voltage signal. The factory setting is such that 10 V DC always corresponds to the nominal differential pressure (ΔpNom). The differential pressure setpoint value is either
a constant value or it comes from a setpoint adjuster or from
switch contacts. The controller compares the differential pressure setpoint value to the actual value and controls the actuator accordingly. Differential pressure parameters and signal voltage range are stored in the control component. Changes made by the customer can easily be made with the TROX FlowCheck App, an adjustment device or a notebook. 

This specification text describes the general properties of the product.

  • Universal controller for room pressure

  • Control of a constant or variable room pressure setpoint
  • Electronic controller for connecting a reference value and tapping an actual value signal
  • The actual value signal relates to the nominal pressure such that commissioning and subsequent adjustment are simplified
  • Stand-alone operation or integration in central building management system

Area of application
  • Room pressure control for ventilation and air conditioning systems in the range from -10 to -50 Pa or +10 to +50 Pa (integrated static transducer)

  • Actuator slow-running; running time 120s for 90°

Installation orientation
  • Either direction

  • Pluggable connection terminals; no additional terminal box required

Supply voltage
  • 24 V AC/DC

Analogue signal:
  • 0 – 10 V DC or 2 – 10 V DC
Bus interface:
  • Modbus RTU
  • BACnet MS/TP
  • MP bus

Interface information
Analogue signal:
  • Room pressure setpoint and actual value
Bus interface:
  • Room pressure setpoint and actual value
  • Damper blade position
  • Fault status

System connections
MP-Bus for optional extensions
  • Gateways for LonWorks, Modbus, BACnet, KNX, e.g. Belimo UK24xxx
  • Fan optimiser e.g. Belimo COU24-A-MP

Special functions
  • Activation Δpmin, Δpmax, Closed, Open, Control Stop by means of external switch contacts/wiring or bus communication

Parameter setting
Parameters specific to VAV terminal unit set at the factory
  • Factory-set nominal pressure
  • Operating values Δpmin, Δpmax factory-set
  • Factory-set signal characteristic
Subsequent adaptation possible with
  • TROX FlowCheck app (NFC or Bluetooth with optional adapter)
  • PC software

Factory condition
  • Electronic controller factory set on control unit
  • Factory set, certified with sticker
  • Controller in OPEN position

TVRD / 200 / D2 / BURN / PRS / V0 / PminPmaxPa
1 Type
TVR VAV terminal unit

2 Acoustic cladding
No entry required: None
D With acoustic cladding

3 Material
Galvanised sheet steel (Standard construction)
P1 Powder-coated RAL 7001, silver grey
A2 Stainless steel construction

5 Nominal size [mm]
100, 125, 160, 200, 250, 315, 400

6 Accessories
No entry required: None
D2 Double lip seal both sides
G2 Matching flanges both sides

7 Attachments (control components)
BURN Universal controller room pressure (VARYCONTROL)

8 Equipment function/Installation location
PRE Room pressure control, extract air
PRS Room pressure control, supply air

9 Operating mode
F Constant value (a setpoint value)
V Variable (setpoint value range)

10 Signal voltage range
0 0 – 10 V DC
2 2 – 10 V DC

11 Operating values for factory setting
Room pressure in Pa
Values for positive pressure: positive sign
Values for negative pressure: negative sign
Δpconst (only with operating mode F)
Δpmin (only with operating mode V)
Δpmax (only with operating mode V)


product information


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Our department for Service-Requests will contact you asap.
For general question regarding products or services you can also call:
Tel.: +43 1 250 43-0| Fax: +43 1 250 43 34