LEFOO LFH30
Higher-accuracy relative humidity and temperature transmitter family. The model is listed in LEFOO’s official downloadable technical document index.
Manufacturer: LEFOO
Official Technical Datasheet
LEFOO original datasheet catalog — search model LFH30 →
Accuracy, measurement range, electrical outputs, probe length and installation environment depend on variant and current revision. Check manufacturer data prior to equipment specification.
LFH30 high-accuracy designation
‘High accuracy’ is not itself a quantified uncertainty specification. Obtain the LFH30-specific RH and temperature tolerances, test conditions, drift/long-term stability and calibration interval from LEFOO before setting a performance claim. In critical humidity control, sensor airflow and contamination matter alongside initial accuracy. Verify the delivered display/interface option and avoid transferring a generic LFH-series accuracy figure.
LFH30 — calibrated humidity and temperature channels
| Selection parameter | Verified manufacturer evidence |
|---|---|
| Relative humidity | 0–100% RH; accuracy ±2% RH at 20°C and 20–80% RH, ≤10 s response in slow-moving air. |
| Temperature | Order-specific 0–50°C or −20 to +60°C ranges; digital temperature accuracy 0.3°C over +5 to +60°C. |
| Outputs | RS485 Modbus, 0–10 V or 4–20 mA; two channel interface determined by variant. |
| Power | RS485 9–35 VDC / 24 VAC ±20%; voltage models 12–35 VDC; current supply set by load. |
| Enclosure | IP65 and optional display, 4–20 mA model without backlit display. |
Engineering note: RH accuracy applies to the stated central calibration condition, not to freezing or condensing duct air. Different passive RTD and digital variants have different temperature specifications; confirm the order suffix and duct location.
Official LEFOO model specification · examined 26 October 2026.
Engineering Selection and Commissioning — LFH30
A high-accuracy temperature-and-humidity measurement requires careful placement and an appropriate reference for acceptance checks. Calibrate or compare under stable conditions, allowing the reference instrument and LEFOO probe to reach thermal equilibrium. Direct sunlight, heat conduction through the wall and nearby humidification jets can create a mismatch larger than the published electronic uncertainty. Confirm the intended output signals, duct or wall version and the maintenance interval for the selected sensing element.
Review the exact LFH30 order code for the intended process, electrical output and measurement range. Note which parameters are manufacturer-declared family options rather than guaranteed features of every suffix. Before routine operation, verify correct supply wiring, engineering units and readings at practical test points. Record the installation conditions and any reference measurement so later drift or control-system errors can be investigated. Maintain access to the maker’s current operating instructions, particularly where variants use different connections or output protocols.
These engineering notes explain how to use the specification table; they do not certify an application or extend the published device limits.