Description
BACnet NO₂ detector with relays and display
The QEL B5-NO2-10P-0-A is a smart NO₂ (nitrogen dioxide) transmitter that helps you keep enclosed parking areas, service bays, and similar spaces safer and better ventilated. It continuously measures low levels of NO₂ from 0–10 ppm using an electrochemical sensor and turns those readings into simple outputs your building automation system and fan controls can use.
On the front, a backlit LCD shows live gas levels, while LEDs indicate relay status and BACnet communication. An internal buzzer and three onboard relays let the device act on rising NO₂ levels directly starting fans, opening dampers, or driving remote alarms without a separate relay panel.
The B5 series speaks BACnet MS/TP over RS-485, so it can plug into most modern BAS networks with no custom gateway. And because it’s housed in a NEMA 4X plastic enclosure, it’s built to handle moisture, dust, and tough mechanical spaces common in garages and industrial sites.
Key Features or Benefits
Monitoring for Garages and Bays
Electrochemical sensing over a 0–10 ppm range gives you the low-level resolution needed for NO₂ from diesel exhaust in enclosed or semi-enclosed spaces.
BACnet Integration
Uses BACnet MS/TP (RS-485), so your BAS can read NO₂ values, alarm status, and relay states as standard BACnet objects instead of through a third-party gateway.
Alarms and Fan Control
Three SPDT relays and an integral buzzer allow the transmitter to start fans, open dampers, or signal remote horns/strobes based on user-set NO₂ thresholds helping you meet ventilation strategies without extra interface hardware.
NEMA 4X Enclosure
The housing is rated NEMA 4X plastic, providing protection against dust, water spray, and corrosion, making it suitable for harsh parking structures and mechanical rooms.
Multiple Output Options for Flexible Design
In addition to BACnet communications, B5 units support standard analog outputs (4–20 mA and voltage ranges such as 1–5 V or 2–10 V), giving you options to tie into drives, PLCs, or non-BACnet controllers.
Serviceable, Long-Term Platform
The B5/Q5 family is designed so sensors can be calibrated and serviced in the field, with published bump-test and recalibration procedures to help keep readings reliable over time.
Key Specs
- Gas Type: Nitrogen Dioxide (NO₂)
- Range: 0–10 ppm
- Sensor: Electrochemical NO₂ cell
- Communications: BACnet MS/TP over RS-485
- Electrical Outputs: 4–20 mA, 1–5 VDC, 2–10 VDC (family)
- Relays: 3 × SPDT relay outputs (B5 series)
- Enclosure Rating: NEMA 4X plastic enclosure
- Supply Voltage: 15–24 VAC or 18–30 VDC, ~0.3 A max
- Operating Temperature: approx. −20 to 50 °C (−4 to 122 °F)
- Display: LCD display
- Indicators: Relay LEDs, BACnet TX/RX LED, Internal Buzzer
