The Vaisala HMP1 is a high-accuracy, interchangeable humidity and temperature probe for indoor spaces. It connects directly to an Indigo200 or Indigo300 transmitter to create a compact wall-mounted measurement system.
The Vaisala HUMICAP® Humidity and Temperature Probe HMP1 is designed for accurate ambient measurement in indoor spaces. Its compact probe head and electronics are integrated into one body, making it ideal for wall-mounted monitoring in laboratories, cleanrooms, data centres, museums, storage areas, production rooms and demanding HVAC applications.
The HMP1 provides relative-humidity accuracy up to ±1.0% RH and temperature accuracy up to ±0.2 °C under typical room conditions. It includes a traceable multipoint calibration certificate and uses Vaisala HUMICAP sensor technology for long-term measurement stability.
The probe can operate independently as a Modbus RTU device or connect to a Vaisala Indigo transmitter. When plugged directly into an Indigo200 Series transmitter or Indigo300 transmitter, it forms a neat single-piece wall-mounted system without requiring a probe cable.
| Measurement Specification | Performance |
|---|---|
| Relative-Humidity Range | 0–100% RH |
| RH Accuracy at +23 °C | ±1.0% RH from 0–90% RH |
| RH Factory-Calibration Uncertainty | ±0.7% RH from 0–40% RH; ±1.0% RH from 40–95% RH |
| RH Response Time | 21 seconds, T63 in still air |
| Humidity Sensor | Vaisala HUMICAP® I |
| Temperature Range | −40 to +60 °C |
| Temperature Accuracy at +23 °C | ±0.2 °C |
| Temperature Factory-Calibration Uncertainty | ±0.1 °C at +23 °C |
| Temperature Response Time | 70 seconds, T63 in still air |
The HMP1 can provide a wide selection of measured and calculated parameters through its digital interface or a compatible Indigo transmitter.
| Feature | Specification |
|---|---|
| Operating Temperature | −40 to +60 °C |
| Storage Temperature | −40 to +60 °C |
| Measurement Environment | Air, nitrogen, hydrogen, argon, helium and oxygen; consult Vaisala for other chemicals |
| Protection Rating | IP50 |
| Operating Voltage | 15–30 V DC |
| Typical Current Consumption | 2 mA |
| Maximum Current Consumption | 200 mA |
| Digital Interface | Non-isolated RS-485 |
| Communication Protocol | Modbus RTU |
| Mechanical Feature | Specification |
|---|---|
| Connector | M12 five-pin A-coded male |
| Approximate Weight | 38 g |
| Probe Material | AISI 316L stainless steel |
| Probe-Body Material | PBT |
| Probe-Body Diameter | 25 mm |
| Overall Length | Approximately 162 mm |
| Probe-Head Diameter | 5 mm |
| Wall Mounting | Probe holder supplied with the HMP1 |
Pairing the HMP1 with an Indigo transmitter adds a local display and additional analog, relay, Ethernet or digital communication options, depending on the selected transmitter.
| Transmitter | Recommended Configuration | Product Link |
|---|---|---|
| Indigo200 Series | Standard compact wall transmitter for one HMP1, with display and practical analog, relay or Modbus options | Vaisala Indigo200 |
| Indigo300 | Rugged IP66 metal transmitter for one HMP1 with local display and up to three analog outputs | Vaisala Indigo300 |
| Indigo510 | Simplified flagship transmitter for one probe, isolated outputs, Ethernet and Modbus TCP | Vaisala Indigo510 |
| Indigo520 | Full flagship transmitter for two compatible probes, isolated outputs, relays, Ethernet and Modbus TCP | Vaisala Indigo520 |
| Requirement | Recommended Configuration |
|---|---|
| Direct Modbus RTU integration | HMP1 used as a standalone RS-485 probe |
| Compact wall display | HMP1 connected directly to Indigo200 |
| Rugged metal wall transmitter | HMP1 connected directly to Indigo300 |
| Ethernet and one probe | HMP1 with Indigo510 and a suitable connection cable |
| Two measurement probes | HMP1 with Indigo520 and suitable connection cables |
| Portable checking and diagnostics | HMP1 connected to an Indigo80 handheld indicator using the appropriate cable |
View the Vaisala Indigo80 Portable Meter
The HMP1 is fully calibrated and adjusted before delivery. The probe stores its own calibration information, allowing it to be exchanged without replacing the complete transmitter. Calibration and adjustment can be performed using Vaisala Insight PC software, a compatible Indigo transmitter or an Indigo80 handheld indicator.
A typical calibration interval is one year, although the correct interval depends on the application, operating conditions and quality-system requirements. Sensor purge can be scheduled or initiated when needed to help remove chemical contamination from the humidity sensor.
Vaisala HMP1, HMP3, HMP4, HMP5, HMP7, HMP8 and HMP9 can be connected to the Vaisala Indigo80 Handheld Indicator using a compatible connection cable.
Portable measurement and field servicing: use Indigo80 to display live humidity and temperature readings, record measurement data, check probe performance, configure settings, and perform field calibration and adjustment. The same Indigo80 can support different compatible probes, making it practical for servicing multiple measurement points.
Vaisala Indigo-compatible HMP probes share the same measurement platform, but their mechanical design and installation method suit different conditions. Use the table below to identify the best starting point for your application.
| Probe | Main strength | Recommended application | Product |
|---|---|---|---|
| HMP1 | Compact wall-mounted probe for indoor environments | Cleanrooms, laboratories, data centres, warehouses and demanding HVAC | Vaisala HMP1 |
| HMP3 | Field-maintainable general-purpose 12 mm probe | Ducts, chambers, paint booths, air-handling units and industrial HVAC | Vaisala HMP3 |
| HMP4 | High-pressure measurement up to 100 bar | Compressed air, breathing air, industrial gases and vacuum systems | Vaisala HMP4 |
| HMP5 | Long probe for high temperatures up to +180 °C | Ovens, kilns, baking processes and high-temperature dryers | Vaisala HMP5 |
| HMP7 | Heated probe for continuous high humidity | Near-condensing chambers, humidifiers, drying processes and other persistently humid conditions | Vaisala HMP7 |
| HMP8 | Adjustable-depth probe for pressurised pipelines | Compressed-air lines, refrigerant dryers and industrial pipelines requiring easy probe removal | Vaisala HMP8 |
| HMP9 | Compact 5 mm probe head with fast response | Tight spaces, rapidly changing air, compact equipment, ducts and data centres | Vaisala HMP9 |
Seacom Process Instruments supplies and supports the Vaisala HMP1 humidity and temperature probe in Malaysia for laboratories, cleanrooms, data centres, museums, warehouses, pharmaceutical facilities and demanding HVAC systems.
Our team can assist with selecting the HMP1 as a standalone Modbus probe or configuring it with an Indigo200, Indigo300, Indigo510 or Indigo520 transmitter according to the required display, analog output, relay and network communication functions.
The Vaisala Indigo200 Series is the standard transmitter platform for one interchangeable Indigo-compatible smart probe, providing local display and practical automation-system connectivity.
The Vaisala Indigo500 Series provides flagship industrial measurement integration: choose Indigo510 for a simplified single-probe system or Indigo520 for full dual-probe capability.
The Vaisala HMP3 is a high-accuracy, field-maintainable probe for industrial HVAC, air-handling units, cleanrooms, paint booths and environmental chambers.
The Vaisala XMP10 Series comprises compact humidity and temperature probes offering accuracy levels up to ±1% RH and ±0.1 °C for demanding HVAC, data-centre and critical-environment applications.
The probes feature analog or Modbus RTU outputs, a standard M8 connector, an IP65-rated body and compatibility with Vaisala Origo10 modular HVAC transmitters.
The Vaisala HMP9 combines a miniature 5 mm probe head with fast-response, high-accuracy humidity and temperature measurement for tight spaces and rapidly changing environments.
The Vaisala Indigo200 Series is the standard transmitter platform for one interchangeable Indigo-compatible smart probe, providing local display and practical automation-system connectivity.
The Vaisala HMT120 and HMT130 provide accurate, stable humidity and temperature measurement for cleanrooms, laboratories, data centres and demanding HVAC applications.
Product transition: HMT120/HMT130 are expected to be phased out. For new projects, the Vaisala Origo10 is the recommended replacement platform.
The Vaisala HMT330 Series was a flagship industrial transmitter platform for humidity, temperature and calculated moisture parameters. It is discontinued and replaced by an Indigo500 transmitter with the HMP probe selected for the application.
The Vaisala PTU300 combined barometric pressure, relative humidity and temperature in one transmitter. The series is discontinued and has been replaced by a suitable Indigo520 barometric-pressure configuration with an application-specific HMP probe.
The Vaisala Origo10 Series comprises modular HVAC transmitters with interchangeable probes for humidity, temperature, CO2 and dew-point measurement.
Available with analog, Modbus RTU and BACnet MS/TP outputs, wall or duct mounting, an optional display and an IP65-rated enclosure.
The Vaisala HMM100 provides reliable humidity measurement and a configurable analog output for integration into environmental chambers and OEM equipment.
The Vaisala MGP261 measures methane, carbon dioxide and humidity directly in raw biogas. Its in-situ design avoids a separate sampling system and helps operators monitor gas quality while protecting downstream equipment.
The Vaisala Indigo520 Supervisor manages up to 100 compatible compact humidity and temperature probes through one host unit. It provides local visibility for the maintenance team and Modbus TCP communication for data centre BMS integration.
Expected availability: early 2027. Enquire with Seacom for configuration and delivery confirmation.
The Vaisala HMP60 is a compact, durable and cost-effective humidity and temperature probe for equipment integration, data loggers, incubators, glove boxes, greenhouses and environmental monitoring systems.
It provides 0–100% RH and −40 °C to +60 °C measurement ranges, low power consumption, interchangeable Vaisala INTERCAP sensor and optional Modbus RTU communication.
The Vaisala HMT140 Wi-Fi Data Logger has been discontinued and is no longer recommended for new monitoring systems.
The Vaisala HMD60 Series provides high-accuracy humidity and temperature measurement for demanding HVAC ducts and light-industrial applications.
The Vaisala HMT360 Series was an intrinsically safe transmitter platform for humidity, temperature and moisture measurement in hazardous areas. It is discontinued and replaced by the Vaisala HMT370EX with an application-specific probe.
The Vaisala HMT370EX provides intrinsically safe humidity and temperature measurement with HMP-series probes. The new DMP370 configuration combines the HMT370EX transmitter with a DMP37X DRYCAP® probe for low-dew-point measurement in hazardous locations.
DMP370 availability: Vaisala plans first deliveries for Q1 2027. Contact Seacom for configuration and project lead time.
