Key facts
- Brand
- Vaisala
- Model
- HMD70
- Industry
- Industrial
- Documents
- 4
- Languages
- JA · EN · FR · DE
- Last added
- 2012-04-06
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Vaisala HMD70U/Y User Manual
The HMD70U/Y series are duct‑mounted three‑wire transmitters for measuring humidity (HMD70U) and humidity plus temperature (HMD70Y). Both models use the HUMICAP®180 humidity sensor, while the HMD70Y adds a Pt 1000 temperature sensor.
The manual covers proper site selection, mounting, grounding, electrical connections, one‑point and two‑point calibration procedures (using the HMI41 indicator and calibration cable 1911622), and routine maintenance such as sensor and filter replacement.
Vaisala HMD70 specifications
| Temperature measurement range | -20 °C to +80 °C |
|---|---|
| Relative humidity range | 0 %RH to 100 %RH |
| Accuracy (after output change) | ±0.5 %RH |
| DC supply voltage range | 0 V to 1 V (selected output) |
All Vaisala HMD70 documents by type
Day-to-day operation, settings and troubleshooting. Start here if the product is already set up.
Questions answered in these manuals
How should the HMD70 be mounted?
The converter is mounted with two screws; drill the mounting holes using the provided template and optionally add calibration holes.
How often should the sensor be calibrated?
A full accuracy check is recommended at least once a year, though the interval may vary with operating conditions and required precision.
What is the recommended calibration interval?
Calibration should be verified once per year, depending on operating conditions and required measurement accuracy.
From: Vaisala HMD70U/Y Humidity and Temperature Transmitter User Manual