This document is the instruction manual of HMP45A/HMP45D humidity and temperature sensor, which introduces the usage methods, connection methods and calibration methods of the sensor.
This manual provides detailed operating instructions for the Vaisala HMP45A and HMP45D probes, which measure relative humidity and temperature. It covers probe construction, sensor types, and the differences between the active voltage output of the HMP45A and the passive Pt100 output of the HMP45D.\n\nThe document includes wiring diagrams, calibration procedures, spare‑part lists, technical specifications, and warranty information. Users are guided on proper installation, maintenance, and field calibration using Vaisala equipment. This manual is written in Japanese.
| Humidity measurement range | 0.8 – 100 %RH |
|---|---|
| Humidity accuracy (20 °C) | ±1 %RH (0‑90 %RH), ±2 %RH (90‑100 %RH) |
| Temperature measurement range | -39.2 … +60 °C |
| Temperature accuracy (20 °C) | ±0.2 °C |
| Supply voltage | 7 – 33 VDC |
| Power consumption | <4 mA |
| Output load impedance | >10 kΩ (to ground) |
| Weight (incl. packaging) | 330 g |
| Housing material | ABS plastic |
| IP rating | IP66 (dust‑tight, water‑proof) |
HMP45A provides an active voltage output (0‑1 V) while HMP45D provides a passive Pt100 resistance output.