HMD40U is a humidity and temperature converter produced by Vaisala. It uses a capacitive polymer film sensor to measure humidity and a platinum resistance sensor to measure temperature. The measurement range is 0-100%RH (no dew) and 10-90%RH (accuracy guaranteed range) from -40 to +60 ° C. The power supply is DC24V, the power consumption is 120mW or less, and the weight is about 160g. The outer dimensions are 80x80x302[φ15x267](mm).
This manual provides the technical specifications of the Vaisala HMD40U (temperature only) and HMD40Y (humidity‑temperature) duct‑mounted sensors, including measurement ranges, accuracy, power requirements, and physical dimensions. It also outlines the sensor’s construction materials and recommended operating conditions.
The document details step‑by‑step installation procedures: opening the packaging, drilling mounting holes, attaching the sensor and cover, connecting optional wiring harnesses, and wiring the sensor to a 24 VDC power source using shielded cable. Safety precautions and troubleshooting guidance are also included. This manual is written in Japanese.
| Temperature measurement range | -40 °C to +60 °C |
|---|---|
| Temperature accuracy | ±0.3 °C (at +25 °C) |
| Supply voltage | 24 VDC |
| Power consumption | 120 mW |
| Housing material | ABS resin |
| Dimensions (L×W×H) | 80 mm × 80 mm × 30 mm |
| Weight | ≈160 g |
The sensor requires a 24 VDC power supply.
Use shielded cable for the connections.
No, the sensor must not be used in environments with organic solvents or alcohol.