COMET H5321 – CO₂ Controller, External Probe, 2 Relays, RS232

COMET H5321 CO₂ Controller with External Probe, 2 Relays, RS232 

The COMET H5321 is a robust CO₂ concentration controller with a separated external probe (1 m cable, optional 2 m or 4 m) and two relay outputs, ideal for use in demanding or aggressive environments. The electronics remain protected while the probe can be flexibly placed – for example, in humid rooms, dusty halls, corrosive areas, or hard-to-reach locations.

With an extended measuring range up to 10,000 ppm, the H5321 is perfectly suited for high CO₂ concentrations such as in greenhouses, breweries, biogas plants, livestock facilities, or industrial processes. When thresholds are exceeded, the two relays automatically activate ventilation, alarms, or other devices. A 3‑color LED indicator and a loud acoustic alarm immediately warn of poor air quality.

The RS232 interface with Modbus RTU protocol (compatible with Advantech ADAM) allows easy integration of the H5321 into monitoring systems. The fully IP65‑rated housing withstands harsh conditions, while the maintenance‑free NDIR sensor ensures years of precise measurement.

The H5321 is the smart solution for safe CO₂ control in challenging environments.

Why the COMET H5321 is the professional choice for external CO₂ control:

• External probe with 1 m cable – electronics stay protected
• Range up to 10,000 ppm – ideal for high concentrations
• 2 potential‑free relays (2 A / 50 V / 60 VA) – direct control
• 3‑color LED indicator + acoustic alarm – instantly visible and audible
• RS232 Modbus RTU – compatible with many systems
• Maintenance‑free thanks to automatic calibration
• Fully IP65‑protected – for humid and dusty environments
• Wide operating temperature range from −30 to +60 °C
• Rugged housing – approx. 360 g
• 3‑year warranty

Technical data:

• CO₂ measuring range: 0 to 10,000 ppm
• CO₂ accuracy: ±(100 ppm + 5 % of reading) at 25 °C and 1013 hPa
• CO₂ resolution: 1 ppm
• External probe: 1 m cable
• Relay outputs: 2 × potential‑free, max. 50 V / 2 A / 60 VA
• LED indicator: Green ≤ 1000 ppm | Yellow 1001–1200 ppm | Red ≥ 1201 ppm
• Acoustic alarm: built‑in beeper, switchable
• Communication: RS232, Modbus RTU, Advantech ADAM
• Power supply: 9–30 V DC
• Operating temperature: −30 to +60 °C
• Protection rating: IP65
• Dimensions: 136 × 150 × 45 mm
• Weight: approx. 360 g
• Warranty: 3 years

Perfect for:

• Humid, dusty, or corrosive environments
• Greenhouses and biogas plants
• Breweries and beverage production
• Warehouses and silos
• Livestock facilities and animal housing
• Shafts and hard‑to‑reach areas
• Industrial processes with high CO₂ levels
• Demand‑controlled ventilation in harsh environments

Installation – flexible and simple

Mount the electronics housing on the wall, place the external probe, connect the relay and power supply, optionally connect RS232 – done. The probe can also be installed in ducts or tanks.

Summary:

• CO₂ level transmitter with two output relays
• Delivered with a CO₂ probe and 1 m connection cable
• Green LED on: CO₂ concentration 0 – 1000 ppm
• Yellow LED on: CO₂ concentration 1001 – 1200 ppm
• Red LED on: CO₂ concentration ≥ 1201 ppm

Scope of delivery:

• H5321
• User manual
• Traceable calibration certificate
• Free TSensor software for configuration of the transmitter