Key facts
- Brand
- Vaisala
- Model
- HMP45A
- Category
- Other
- Industry
- Industrial
- Documents
- 3
- Languages
- EN · JA · ZH
- Last added
- 2023-10-18
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Vaisala HMP45A/D Humidity and Temperature Probes User's Guide
The Vaisala HMP45A and HMP45D probes are designed for measuring relative humidity and temperature. The HMP45A features an active voltage output for temperature, while the HMP45D uses a passive resistive output (Pt 100). Both models utilize a HUMICAP®180 capacitive sensor for humidity and platinum sensors for temperature, protected by a standard membrane filter.
Read onlineVaisala HMP45A specifications
| Humidity Measurement Range | 0.8...100 %RH |
|---|---|
| Humidity Accuracy at +20 °C | +1 %RH (factory) |
| Response Time (90%) | 15 s |
Source: Vaisala HMP45A/D Humidity and Temperature Probes User's Guide
All Vaisala HMP45A 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 often should the probes be calibrated?
Calibration and maintenance should be performed at regular intervals, with a recommended interval of one year.
From: Vaisala HMP45A/D Humidity and Temperature Probes User's Guide
Can the HMP45D be used with the HMI41 indicator?
No, the HMP45D cannot be used with the HMI41 indicator because the passive temperature signal results in error messages.
From: Vaisala HMP45A/D Humidity and Temperature Probes User's Guide
How does the temperature output differ between HMP45A and HMP45D?
HMP45A provides an active voltage output (0‑1 V) while HMP45D provides a passive Pt100 resistance output.
What calibration methods are supported by the sensor?
The sensor can be calibrated on site using single‑point or two‑point calibration.
Can the sensor be used in high humidity environments?
Yes, the sensor maintains high accuracy in high‑humidity conditions.