

Carbon Dioxide (CO2) Gas Detection
The Bacharach MGS-400 series is a comprehensive and flexible solution for CO2 gas detection, consisting of three main components: CO2 sensors, Controllers and an innovative Mobile App. Bacharach’s CO2 gas detection solutions provide continuous CO2 safety monitoring to support regulatory compliance in accordance with EN 378, ASHRAE 15 and CSA B52. However, it is also important to note that specific exposure limits can differ from country to country. For example, in the UK, EH40 guidance sets the Short Term Exposure Limit (STEL) at 15,000ppm and Long Term Exposure Limit (LTEL) at 5,000ppm. Some EU countries, such as Sweden, have the STEL limit set at 10,000ppm. What’s important to know is that whatever the regional requirements are- the MGS-400 series Carbon Dioxide monitors have you covered.
MGS-400 Series Gas Detection
Refrigeration Safety Compliance has never been more intuitive
Bacharach provides innovative solutions designed for extreme temperature refrigeration environments, helping you reduce your Carbon Dioxide refrigerant emissions for Safety Compliance. Suitable for: Machinery Rooms, Walk-in Freezers & Cold Rooms, Industrial Cold Storage, Chiller Rooms.

All Gas Detectors Include:
- Network Enabled Refrigerant Detection System
- Integrated Audio-Visual Alarms
- Multiple Cable Glands
- Easy to Wire
- Low Temperature Performance
- Refrigerant Specific Sensors
- IP66-rated protection with optional IP41 also available
Mobile App User Interface
Quick, easy and intuitive commissioning, configuration and maintenance requires no special training. No tools required to set alarm levels and behavior. The innovative and intuitive app makes compliance with safety standards easy and effective for your Carbon Dioxide gas detection application.
Convenient Networking Connections for Improved Scalability
The MGS-400 series CO2 detection units have multiple cable glands for convenient wiring connections, helping reduce installation times. Sensors in a system can be daisy-chained for up to 4500 feet. The MGS-408 and 402 system controllers are both Modbus master and slave devices that provide central alarming and power for multiple units as well as aggregated connectivity to a building automation system.


Low Temperature Performance
The MGS-400 series of gas detectors are suitable for use in cold rooms and freezers down to -40°F/C. Temperature compensated measurements also mitigate false alarms and optimizes accuracy in refrigeration applications.
Integrated Audio-Visual Alarms
The on-board audio-visual alarm notifications support the MGS-400 series compliance with ASHRAE 15 and EN 378. Safety guidelines from OSHA PEL, NIOSH REL and ACGIH TLV provide complimentary guidelines for safe CO2 exposure levels as:
Exposure Type | Value (ppm) |
---|---|
Threshold Limit Value: | 5,000 (0.5%) |
Short Term Exposure Limit: | 30,000 (3.0%) |
Immediately Dangerous to Life and Health: | 40,000 (4.0%) |


IP66 Rated Protection
The MGS-400 series offers IP66 rated protection, designed for use in areas that are regularly washed down or prone to water or condensation. There is an additional option for IP41 rated protection.
Easy Wiring Access
The MGS-400 gas detectors are designed for easy access to all terminal blocks, and specifically include separate power terminals for in and out connections.


MGS-400 Replaceable Sensor Module
Sensors are easily replaced by twisting out the sensor module and twisting in a new one. Any sensor module can be used in all detectors providing for future-proof re-use should the need for a change in the type of gas detected occur.
Find the Right MGS-400 Series Gas Detector for Your CO2 Installation
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MGS-410 | MGS-450 | MGS-450 | MGS-460 | |
Enclosure | IP66 | IP41 | IP66 | IP66 |
Relays | - | 3 | 3 | 3 |
Communication | Modbus | Modbus | Modbus | Modbus |
Output | - | Analog | Analog | Analog |
Sensor | Integrated | Integrated | Integrated | Remote |
0-5,000ppm CO2 | 6302-0090 | 6302-1090 | 6302-2090 | 6302-4090 |
0-10,000ppm CO2 | 6302-0091 | 6302-1091 | 6302-2091 | 6302-4091 |
0-20,000ppm CO2 | 6302-0092 | 6302-1092 | 6302-2092 | 6302-4092 |
0-30,000ppm CO2 | 6302-0093 | 6302-1093 | 6302-2093 | 6302-4093 |
0-40,000ppm CO2 | 6302-0094 | 6302-1094 | 6302-2094 | 6302-4094 |
0-50,000ppm CO2 | 6302-0095 | 6302-1095 | 6302-2095 | 6302-4095 |
For further technical information visit the MGS-400 series gas detection page.
Technical Specifications
Installation | Multiple cable entries, Daisy-chain power and communications, Separate "in and out" wiring terminals |
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Performance | EN 378 Safety Compliance and ASHRAE 15 Safety Compliance Fast response time w/flush mount sensors Wide operating range: -40C to +50C, temperature compensation for accurate readings |
Maintenance | Pre-calibrated sensor modules. Semi-automatic manual calubration |
Diagnostics | Fault code reporting, "Calibration Due" indicator, Sensor exposure counter |
Status Indicator | Tri-color LED (green, red, orange) |
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Buzzer | 72dB @ 10 cm |
Ambient Conditions | Humidity: 5 to 90% RH, non-condensing, Pressure: 23.6 to 32.5 inch Hg / 800 to 1,100 mbar |
Other gases and ranges | NH3: 100 / 1,000 / 5,000 ppm / 100% LEL, O2: 30 Vol%, Combustible Gases - Semiconductor (R-290, R-600, CH 4, R-600a, HC-12a, R-717): 5,000 ppm, Combustible Gases - Catalytics (R-600, CH4, R-290, NH3): 100% LEL, NO2: 20ppm |
MGS-400 Series System Controllers
The MGS-400 Series System Controllers
The MGS-402 provides Modbus master and slave devices along with both integrated horn and strobe. The MGS-408 also has Modbus master and slave devices along with integrated horn. Sensors in a system can be daisy-chained for up to 4500 feet.

MGS-402 Gas Controller

MGS-408 Gas Controller
Features | MGS-402 | MGS-408 |
---|---|---|
Channels | 2 | 8 |
Relays | 3 | 3 |
Analog Outputs | 2 | - |
Modbus RTU | Master (sensors) Slave (BAS) |
Master (sensors) Slave (BAS) |
Integrated Horn | Yes | Yes |
Integrated Strobe | Yes | Optional |
Beacon Output | 2 | 1 |
Remote Silence Input | 1 | - |
Sensor Inputs | MGS-410 | MGS-410, 450, 460, 550 |
Power | 120-240VAC 24VDC |
120-240VAC 24VDC |
For further information, visit the Bacharach MGS-400 series gas detector controllers page.