Growlink ESM-2 Climate Sensor for CO2, Humidity, Temperature, and Pressure
The ESM-2 is a modular 4-in-1 probe that reads CO2, humidity, temperature, and pressure on one hardwired RS485 daisy chain. Power runs on 15-30 VDC from the Growlink control panel. The sensing module unscrews from the body for swap-out at calibration intervals. Each unit ships with a unique MAC address printed on the box. The chain map matches a known room and chain position from the start.
Climate Sensor Built for Canopy-Level Grow Room Monitoring
The ESM-2 sits at or slightly above canopy height to read the air the plants actually breathe. CO2 measuring ranges run 0-2000, 0-5000, or 0-10000 ppm with ±50 ppm + 2% accuracy on the 2000 ppm range. Humidity tracks 0-95% RH non-condensing with ±3% accuracy across 20-80% RH at 25°C. A 120Ω terminating resistor at the last junction box keeps the RS485 daisy chain stable in noisy grow environments.
Key Features
- 4-in-1 Probe: Measures CO2, humidity, temperature, and pressure from a single sensor body at canopy height.
- RS485 Daisy Chain: Hardwired daisy chain reduces interference and dropouts vs. wireless mesh sensors in dense grow rooms.
- 15-30 VDC Power: Runs on the Growlink control panel's existing 14 AWG plus/minus conductor pair.
- Replaceable Sensing Module: The sense element unscrews from the body for calibration swap-outs without pulling the whole unit.
- Selectable CO2 Range: Configure 0-2000, 0-5000, or 0-10000 ppm depending on whether the room is ambient or CO2-enriched.
Technical Specifications
| Specification | Value |
|---|---|
| Measurements | CO2, humidity, temperature, pressure |
| CO2 Ranges | 0-2000 ppm / 0-5000 ppm / 0-10000 ppm |
| CO2 Accuracy | ±50 ppm + 2% of measured value (0-2000 ppm range) |
| Humidity Range | 0 - 95% RH (non-condensing) |
| Humidity Accuracy | ±3% RH at 25°C, 20-80% RH |
| Power Input | 15-30 VDC |
| Power Wiring | 14 AWG +/- conductors from Growlink control panel |
| Communication | RS485 daisy chain |
| Cable Type | Twisted shielded pair, 100-130Ω impedance |
| Chain Termination | 120Ω resistor at last junction box |
| Sensing Module | Replaceable (unscrews from body) |
| Identification | Unique MAC address printed on each unit |
| Compatible Controllers | Growlink environmental control panels |