HD51.3DP147 all-in-one anemometer for coastal environment weather monitoring

Shown below is an HD51.3DP147 all-in-one anemometer for coastal environment applications. It measures wind speed, wind direction, temperature, humidity, barometric pressure, and solar irradiance with a single instrument. Multiple output types are supported, and the MODBUS-RTU output is used by most users.

The HD51.3D… series is very similar to the HD52.3D… series. The main advantage is that HD51.3D is more rugged and it satisfies the the requirements of the MIL-STD-810G Method 509.6 and EN ISO 9227:2017 (salt fog anti-corrosion test). For Singapore customers, we recommend this model for applications in coastal environments.

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Senseca PYRAsense03 class C pyranometer with MODBUS-RTU output

Related instruments Pyranometers, Weather station

Shown below is a Senseca PYRAsense03 class C pyranometer with MODBUS-RTU output:

Top view
Botton view

The new PYRAsense series pyranometers are equipped with diagnostic sensors of internal temperature, pressure, and humidity. The meters are with compact size and easy to mount.

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Wireless data logger for CO2 and indoor environment measurement

Related instruments Air quality sensors, Wireless & web data loggers

Shown below is a wireless data logger from Senseca for temperature, humidity, pressure, CO2 and VOC index measurement:

Shown below is the screenshot from the data logger software. An HD35APD base unit is used by this customer.

The absolute humidity and wet bulb temperature are calculated from the temperature and relative humidity.

This instrument is great for long-term indoor thermal environment and air quality monitoring. The instrument is powered by USB, and it is possible to be powered by standard phone chargers or power banks.

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Handheld instrument for VOC index and CO2 measurement

Related instruments Air quality sensors

Shown below is a handheld instrument for CO2 and VOC index measurement, in addition to temperature, humidity, barometric pressure, and air speed measurement.

The meter is HD32.3TC thermal comfort data logger for microclimate index and indoor air quality (IAQ) measurement. There are two probes in the system:

  • Left: HP3217BV4 probe for CO2, VOC index, temperature, relative humidity, and barometric pressure measurement
  • Middle: AP3203.2 probe for omnidirectional air speed measurement

The HD32.3TC can be used for other applications, as described in other posts:

LoRaWAN data logging system for micro-climate monitoring

Related instruments Temperature & humidity, Wireless & web data loggers

Shown in the photo below is a LoRaWAN data logging system for micro-climate monitoring (soil temperature, air temperature & humidity), deployed in a public garden in Singapore:

The following instruments were used:

There are two LoRaWAN data loggers in the system:

  • LR35W1NTC temperature & humidity LoRaWAN data logger: this data logger supports 1 combined temperature & humidity probe
  • LR35WH general purpose data logger: this data logger supports 4 general input channels. In this installation, 4 PT100 temperature probes were connected.

The battery life of both loggers is longer than 2 years.

A few outdoor-type LoRaWAN gateways with 4G connectivity were deployed to provide network access. The signal coverage is around 1 km in an environment without tall buildings (with trees and other structures). The signal strength is reliable, based on the first few weeks of operation.

The data are automatically uploaded to the Delta OHM cloud. The end users can review the results online in real-time. The cloud service is free of charge.

OTM supplied all instruments and provided installation and maintenance services for this project.

Instrument for outdoor micro-environment measurement

Related instruments Temperature & humidity, Air speed & wind, Thermal comfort

Shown below is a system integrated by OTM for outdoor micro-environment measurement:

The system consists of the following components:

  • HD52.3DP17: ultrasonic anemometer for wind speed, wind direction, temperature, humidity, and solar irradiance measurement
  • TP876.1.I: 50 mm globe thermometer
  • HD33MT.4: data logger supporting 4G communication

At the customer’s request, we also customized a stand for the system. A similar system was customized by OTM before. The new system has castor wheels and it is easy to move the system around for measurement.

The power consumption of the system is very low. With the internal 3.4 Ah battery, the system can run for around 5 days without charging. The data can be directly downloaded via a USB cable. With a 4G SIM card, it is possible to connect the data logger to the cloud.

Wireless data loggers for construction site dust level monitoring

Related instruments Wireless & web data loggers, Air quality sensors

Shown below are two wireless data loggers for PM1.0, PM2.5, and PM10 measurements and they will be deployed by a construction company for construction site dust level monitoring:

The instruments are:

The model HD35EDWPM is an upgraded version of the system shown in this post. The new model integrates the sensing part and the data logging part into a single unit.

Shown below is the software screenshot:

The system can be deployed for construction site dust level monitoring. The data logger is rain-resistant and can be deployed outdoors. A clamp is included for each unit and the mechanical mounting is very easy. If the data logging interval is set to 5 min or 10 min, the internal memory can store years of measurement data.

HD9008T7AC Meteorological temperature transmitter with 4-20 mA output

Related instruments Temperature & humidity

Shown below is an HD9008T7AC meteorological temperature transmitter with 4-20 mA output:

The probe diameter is 26 mm and it is compatible with HD9007A-1 or HD9007A-2 solar radiation shield.

It measures air temperature only and it is suitable for applications not requiring relative humidity information (for example, solar panel performance monitoring).

HD2013.3 rain detector for rain status monitoring

Related instruments Weather stations

Shown below is an HD2013.3 rain detector from Delta OHM:

The rain detector can be used in an automated control system, e.g. to start a pump immediately when there is rain. It detects the rain status only (on/off of rain) but does not measure the rainfall amount (for this purpose, a rain gauge should be used). The detector detects rain by the wetness of the sensing part (the green color pad in the photo).

There are multiple types of output types available:

  • RS484 MODBUS-RTU or proprietary protocol
  • Analogue (0/4-20 mA by default or 0-10 V on request)
  • Voltage-free normally open contact

The voltage-free normally open contact can be connected to a relay to control other equipment.