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Vaisala HMD40U/HMD40Y Humidity Sensor Operating Instructions
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.
Vaisala HMD40 specifications
| Cable seal type (part 1) | ST2.9x19‑C‑Z DIN 7981 |
|---|---|
| Cable seal type (part 2) | ST4.2x16‑C‑Z DIN 7981, 4‑pos |
| Cable seal diameter | T2.9x13‑C‑Z DIN 7981 |
| Screwdriver size for seal installation | 7.10 mm |
Source: Vaisala HMD40/50 User Manual
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Day-to-day operation, settings and troubleshooting. Start here if the product is already set up.
Questions answered in these manuals
What power supply should be used for the sensor?
The sensor requires a 24 VDC power supply.
From: Vaisala HMD40U/HMD40Y Humidity Sensor Operating Instructions
What type of cable is required between the power supply, controller, and sensor?
Use shielded cable for the connections.
From: Vaisala HMD40U/HMD40Y Humidity Sensor Operating Instructions