Key facts
- Brand
- Vaisala
- Model
- HMW40
- Industry
- Industrial
- Documents
- 3
- Languages
- JA · EN
- Last added
- 2012-04-06
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Vaisala HMW40 Humidity/Temperature Converter Datasheet
The HMW40 is an indoor wall‑mounted humidity and temperature converter designed for precise environmental monitoring. It uses a capacitive polymer‑film sensor to measure relative humidity and a temperature sensor covering a wide range.
Key features include a 4‑20 mA output proportional to 0‑100 % RH, a measurement accuracy of ±0.5 % RH, and a compact ABS housing weighing about 60 g. The device operates from a 24 V DC supply and consumes approximately 120 mW. This manual is written in Japanese.
Vaisala HMW40 specifications
| Model | HMWM0U / HMWMOY |
|---|---|
| Product Name | Indoor wall‑mounted humidity/temperature converter |
| Sensor Type | Capacitive polymer‑film humidity sensor |
| Humidity Range | 0 % – 100 % RH |
| Temperature Accuracy | ±0.3 °C |
| Output | 4‑20 mA (0‑100 % RH) |
| Power Supply | 24 V DC |
| Power Consumption | 120 mW |
| Housing Material | ABS resin |
| Dimensions (W×H×D) | 80 mm × 80 mm × 26 mm |
Source: Vaisala HMW40 Humidity/Temperature Converter Datasheet
All Vaisala HMW40 documents by type
Ratings, dimensions and ordering codes, for selection and design work.
Mounting, wiring and first power-up. Read it before the hardware goes in.
Questions answered in these manuals
What is the humidity measurement range of the HMW40?
The HMW40 measures humidity from 0 % to 100 % RH.
From: Vaisala HMW40 Humidity/Temperature Converter Datasheet
What output signal does the HMW40 provide?
It provides a 4‑20 mA current loop proportional to the measured humidity (0‑100 % RH).
From: Vaisala HMW40 Humidity/Temperature Converter Datasheet
How do I know the correct mounting position?
The guide shows a sign pointing upward that indicates the correct mounting position.
What should I do if the air holes become dusty after mounting?
Cover the air holes with the provided cover and remove it when the transmitter is taken into use.
What is the overall humidity accuracy of the HMW40?
The overall humidity accuracy is ±0.3 % RH at 25 °C.
How does temperature affect humidity measurement?
The humidity measurement has a temperature dependence of 0.01 % RH per degree Celsius.