The Belimo 22RTM-5U00D is a wall-mount active room sensor measuring CO2, Relative Humidity, Dew Point, and Temperature with native Modbus RTU and BACnet MS/TP communication for direct integration with any modern building automation system, plus an MP-Bus channel for Belimo network applications. The high-contrast ePaper touch display (2.72 x 2.44 inch) provides on-device readout of all measured values and direct setpoint adjustment by the occupant — no smartphone required. The sleek white (RAL 9003) housing matches commercial interior finishes and mounts to a single-gang box or flat to drywall.
Key Features
Native BACnet MS/TP + Modbus RTU
Direct integration with any major BAS — no gateway, no protocol converter. The room sensor exposes all measured values, setpoints, and configuration parameters as standard BACnet objects or Modbus registers. MP-Bus is also available for Belimo damper actuator networks.
ePaper Touch Display
2.72 x 2.44 inch high-contrast ePaper touch screen shows live values for all measured parameters. Occupants tap directly on the display to nudge the temperature setpoint. Optional 4-digit access code blocks unauthorized adjustments.
NDIR Dual-Channel CO2 Sensor
Non-dispersive infrared dual-channel CO2 element compensates for sensor aging without requiring weekly fresh-air calibration (ABC logic). Suitable for 24/7 occupancy applications. Recommended recalibration after 5 years.
Capacitive Humidity Sensor
Long-term-stable capacitive RH element with ±2% accuracy between 0-90% RH at 25°C and ±0.25% RH/year drift. Dew point is calculated and provided as an additional measured value.
Configurable Setpoint Range
Define how far the occupant can shift the setpoint above or below the BAS schedule. All limits, scaling, and offsets are configurable via the Belimo Assistant App or BAS object writes — no DIP switches, no jumpers.
Universal 24 V Power
AC/DC 24 V (19.2-28.8 V) supply tolerance. Spring-loaded terminals accept 0.25-1.5 mm² conductors with back, top, or bottom cable entry — flexible mounting for both new construction and retrofit.
Technical Specifications
| Specification | |
|---|---|
| Measured Values | CO2, Relative Humidity, Dew Point, Temperature |
| Output Signal | Modbus RTU + BACnet MS/TP digital + 1x Digital Input |
| Communication | MP-Bus + Modbus RTU + BACnet MS/TP |
| Temperature Range | 32...122°F [0...50°C] (default, configurable) |
| Temperature Accuracy | ±0.3°C @ 25°C [±0.5°F @ 77°F] |
| Humidity Range | 0...100% RH (default, configurable) |
| Humidity Accuracy | ±2% between 0...90% RH @ 77°F [25°C] |
| Humidity Long-Term Stability | ±0.25% RH per year |
| Dew Point Range | -58...122°F [-50...50°C] |
| CO2 Sensor Technology | NDIR (Non-Dispersive Infrared) Dual-Channel |
| CO2 Range | 0...2000 ppm (default, configurable) |
| CO2 Accuracy | ±(50 ppm + 2% of measured value) |
| CO2 Long-Term Stability | ±20 ppm per year |
| Display | ePaper Touch Display + LED |
| Setpoint Adjustment | Yes (via Display App or ePaper touch) |
| Nominal Voltage | AC/DC 24 V |
| Voltage Range | 19.2...28.8 V (AC or DC) |
| Power Consumption | 1 VA AC / 0.5 W DC |
| Electrical Connection | Spring-loaded terminal 0.25-1.5 mm² |
| Cable Entry | Back, top, and bottom side |
| Housing | PC, white, RAL 9003 |
| Protection | IP30 / NEMA 1 |
| Ambient Temperature | 32...122°F [0...50°C] |
| Ambient Humidity | Max 95% RH, non-condensing |
| Storage Temperature | -40...160°F [-40...70°C] |
| Display Size | 2.72 x 2.44 in [69 x 62 mm] ePaper touch |
| Certifications | UL/cULus per UL60730-1, IEC/EN 60730-1, CE, ISO 9001 |
| Warranty | 5 Years |
Documentation
Frequently Asked Questions
What does the 22RTM-5U00D actually measure?
The 22RTM-5U00D measures co2, relative humidity, dew point, temperature (calculated). All values are available simultaneously over mp-bus + modbus rtu + bacnet ms/tp.
Does the BACnet/Modbus version still need analog wiring?
No. The 5U00 series provides all measured values and accepts setpoint writes over Modbus RTU or BACnet MS/TP — only power (24 V) and the digital network conductors are required at the wall sensor. A digital input is also provided on-board for window-open, occupancy, or override contacts.
How does the occupant change the setpoint?
The ePaper touch display shows the current setpoint and accepts touch input directly on the device. An optional 4-digit access code can be enabled to prevent unauthorized changes, and the BAS can constrain how far the setpoint may deviate from the schedule.
Does the CO2 sensor need regular calibration?
The CO2 element uses NDIR dual-channel technology, which compensates for component aging using a sealed reference duct — fresh-air ABC calibration is not required. This makes it suitable for 24/7 occupied spaces where ABC sensors would never see clean outdoor air. Recalibration is recommended after 5 years.
What's the power requirement?
AC/DC 24 V nominal (19.2-28.8 V tolerance). Power consumption is 1 VA AC or 0.5 W DC. Use Class 2 supply per UL60730-1; cable type CL2 or higher for USA/Canada installations.
How does this mount?
PC housing in white RAL 9003 mounts directly to a single-gang electrical box (back-side cable entry) or flat to drywall (top or bottom cable entry). Spring-loaded terminals accept 0.25-1.5 mm² conductors — no screws to overtighten.
- Sensor Type:
- Wall Mount
- Temperature Element:
- BACnet/Modbus
- Supported Protocols:
- BACnet/Modbus
- Humidity Element:
- 2%
- CO2 Element:
- Yes
- Setpoint:
- Setpoint
- Override:
- No Override
- Display:
- ePaper Display
- Material:
- Plastic
