Description
Central gas detection controller for up to 40 sensors with onboard relays and BAS integration
The QEL M-Controller 2 is the “brain” of a gas detection system, bringing all your gas sensors into one easy-to-read panel. It can monitor up to 32 digital QEL gas transmitters and 8 analog 4–20 mA sensors (for other gases or process signals), so you can oversee multiple zones—like parking levels, service bays, or mechanical rooms—from a single controller.
Built-in relays and alarm outputs let the M-Controller 2 do more than just display numbers. It can automatically start fans, trigger horn/strobe alarms, or shut down equipment based on gas levels, using three onboard relays and optional remote relay panels for up to 99 total relay outputs.
A loud internal buzzer and dedicated horn/strobe terminals help meet code-driven ventilation and alarm requirements in parking garages and similar spaces.
For integration, the M-Controller 2 speaks Modbus RTU out of the box and can be ordered with BACnet/IP, so your building automation system can monitor gases, alarms, and fan commands alongside the rest of your HVAC. Setup is handled either from the front keypad and backlit LCD display or via included M-View software over USB, which speeds up commissioning and future changes.
Key Features & Benefits
One Controller for Up to 40 Sensors
Supports up to 32 QEL digital gas transmitters on four RS-485 ports plus 8 analog 4–20 mA inputs, so you can mix carbon monoxide, NO₂, and other gas or process sensors on one platform.
Built-In Fan and Alarm Control
Three onboard SPDT relays can be programmed with voting, averaging, on/off delays, and latch options to drive exhaust fans, makeup air, or other loads based on actual gas levels.
Expandable Relay Capacity
Supports M-Relay modules addressed up to relay 99, giving you plenty of outputs for staged fans, dampers, and other equipment as projects grow.
Clear Local Alarms
Includes a 90 dB internal buzzer plus dedicated horn and strobe terminals with their own 24 VDC power, helping meet local code requirements and making alarms hard to miss in noisy garages or plants.
BAS-Ready Communications
An RS-485 output port supports Modbus RTU, and an optional BACnet/IP card lets your BAS read gas levels, alarm status, and relay states without custom gateways.
Easy Programming and Service
A four-line backlit LCD and 6-button keypad give you direct access in the field, while M-View PC software (and included USB cable) make it easy to copy settings, log data, and audit configurations.
Designed for Real-World Applications
Listed applications include underground parking garages, municipal service garages, water treatment plants, warehouses, and aircraft hangars—sites where reliable, automated ventilation control is critical.
Key Specs
- Max Digital Sensors: 32 QEL digital transmitters on four RS-485 ports
- Max Analog Inputs: 8 channels, 4–20 mA
- Onboard Relays: 3 × SPDT Form C dry-contact relays (5 A @ 30 VDC / 250 VAC resistive)
- Remote Relays: Up to 99 relays via M-Relay modules (2, 4, 6, or 8 relays per module)
- BAS Interface: Modbus RTU (standard) or optional BACnet/IP over RS-485/Ethernet
- Alarm Outputs: 2 dedicated horn/strobe terminals with 24 VDC, 750 mA max
- Supply Voltage: 18–30 VDC or 15–24 VAC, 24 V nominal
- Operating Temperature: −4 to 122 °F (−20 to 50 °C)
- Enclosure (Standard): Steel, epoxy-painted, NEMA 1; optional NEMA 4X polycarbonate enclosure available
- Display / Interface: Four-line backlit LCD with 6-button tactile keypad
