HD33MT.4 Data Logger for Weather Station

Inputs and ports

• 4 independently configurable analog inputs: 0...50 mV, -50...+50 mV, 0...1 V, 0...10 V, 0...20 mA or 4...20 mA, Pt100, Pt1000, thermocouple, potentiometer or pyrgeometer.
• 2 counting inputs for potential-free contacts, for example a tipping bucket rain gauge and a cup anemometer.
• 1 RS485 port with Modbus-RTU protocol, configurable as “Master” or “Slave”. With an optional module, the logger joins an ETHERNET network and communicates over MODBUS TCP/IP.
• 1 SDI-12 “Master” port, compatible with version 1.3 of the SDI-12 protocol.
• 2 potential-free contact alarm outputs.

On request, an M12 connector input is available for a combined relative humidity and temperature probe with NTC sensor, or for a temperature-only probe with NTC sensor. With the humidity and temperature probe connected, the logger also calculates the dew point.

Mobile transmission and remote control

Thanks to 4G/3G/GSM(2G)/GPRS transmission, there is no need to remove the logger or travel to the site to download the data to a PC: the instrument sends the data by email or FTP and can upload them to an HTTP server, such as the Delta OHM portal “www.deltaohm.cloud”.

The logger can also be controlled remotely, either with commands sent by SMS or through a direct TCP/IP connection over the mobile network from a remote PC connected to the internet.

Alarms

For every measured variable you can set two alarm thresholds (high and low), the alarm hysteresis and a delay before the alarm is raised. Threshold violations can be reported by email or SMS, and two potential-free contact alarm outputs are also available.

Clock, power and housing

• The internal clock is highly accurate and very stable across the whole operating temperature range; it supports automatic time synchronization with an HTTP reference server.
• An optional 12 V / 3.4 Ah rechargeable battery, fitted inside the case, prevents data loss if the external supply fails. The battery charger is built in.
• The logger can run from a solar panel and is designed for low consumption: it keeps working for weeks even if the solar panel does not recharge the battery.
• Supply of 18...30 Vdc with the rechargeable battery, or 7...30 Vdc (without ETHERNET module) / 12...30 Vdc (with ETHERNET module) without it.
• A switched power output powers the sensors only when a measurement is due.
• IP 65 housing and optional custom LCD display.

Cloud

At regular, configurable intervals, the logger can send data automatically to an HTTP server, in particular the Delta OHM portal “www.deltaohm.cloud”. Data can then be viewed from anywhere in the world with a web browser and an internet connection, including on tablets, smartphones and laptops.

HD35AP-S PC software

The HD35AP-S software, a free download from the Delta OHM website, configures the logger, shows real-time measurements in graphic and numeric form and downloads the data into a database. Downloads can run automatically at regular intervals or on user request.

The database can display data from several loggers at the same time. The connection is multi-client: data can be stored in a remote database on the PC's local network and viewed from any PC on that network through HD35AP-S.

The HD35AP-CFR21 option is enabled by a USB hardware key, which plugs into any PC on the same local network as the PC running HD35AP-S. On top of the basic software features, it protects logged data and configuration in line with the FDA 21 CFR part 11 recommendations. In particular, it provides:

• Traceability of the activities carried out with the software (audit trail), for example which users logged in and what changes were made to the logger configuration.
• User access management for logger configuration and for viewing database data. Each user can have a separate password, and there are three access levels (Administrator, Super-user and Standard user), each with its own set of permitted operations.

Technical specifications

• Power supply: with rechargeable battery, 18...30 Vdc; without rechargeable battery, 7...30 Vdc without ETHERNET module or 12...30 Vdc with ETHERNET module
• Consumption at 12 Vdc: < 3 mA without ETHERNET module and no GSM/3G activity; ~ 200 mA with ETHERNET module and no GSM/3G activity; < 1 A peak during GSM/3G activity
• Battery: optional internal lead battery, 12 V / 3.4 Ah; maximum charging current 1 A; autonomy depends on the number and type of connected sensors
• Switched power output: with solar panel supply (+Vpanel input), it delivers the internal lead battery voltage (12 V nominal); with supply from the +Vdc input, it delivers that input voltage; active only when the external sensors need power
• Antenna: external
• Measuring interval: 1, 2, 5, 10, 15, 30 s / 1, 2, 5, 10, 15, 30, 60 min
• Logging interval: 1, 2, 5, 10, 15, 30 s / 1, 2, 5, 10, 15, 30, 60 min
• Internal memory: circular, or stops logging when full; from 242,850 to 858,070 samples, depending on the number of measured variables
• Alarm: email and SMS alarm messages; two potential-free, normally open (NO) contact outputs, max. 300 mA at 30 Vdc resistive load
• Display: optional custom LCD
• LED indicator: 2-color LED; power on (flashes red) and GSM/3G activity (flashes green)
• PC connection: USB port with mini-USB connector
• ETHERNET connection: RJ45 connector (only with the optional ETHERNET module)
• Internal clock drift: ± 2 ppm (0...+40 °C) / ± 5 ppm (-40...+70 °C)
• Operating conditions: -40...+70 °C / 0...100 %RH for the version without LCD; -20...+70 °C / 0...100 %RH for the version with LCD
• Weight: approx. 1 kg
• Housing: 270 x 170 x 110 mm (external antenna excluded), polycarbonate (PC), IP 65 protection (with the USB connector cap fitted)
• Installation: on a 40 mm diameter mast

Measurement specifications

Temperature (with HP3517WTC... or TP350NTC... probe)

• Sensor: NTC 10 kΩ at 25 °C
• Range: -40…+105 °C
• Instrument resolution: 0.1 °C
• Accuracy: ± 0.3 °C within 0...+70 °C / ± 0.4 °C outside that range
• Stability: 0.1 °C / year

Relative humidity (with HP3517WTC... probe)

• Sensor: capacitive
• Range: 0...100 %RH
• Instrument resolution: 0.1 %
• Accuracy: ± 1.8 %RH (0...85 %RH) / ± 2.5 %RH (85...100 %RH) @ T=15...35 °C; ± (2 + 1.5% of reading)% @ T=remaining range
• Sensor operating temperature: -40…+80 °C
• Response time: T90 < 20 s (air speed = 2 m/s, without filter)
• Temperature drift: ±2% over the whole operating temperature range
• Stability: 1% / year
• Calculated variable: dew point

Atmospheric pressure

• Sensor: piezoresistive
• Range: 300... 1100 hPa
• Instrument resolution: 0.1 hPa
• Accuracy: ± 0.5 hPa (800...1100 hPa) at T=25°C; ± 1 hPa (300...1100 hPa) @ T=0...50°C
• Stability: 1 hPa / year
• Temperature drift: ±3 hPa between -20...+60 °C

Pt100/Pt1000

• Range: -200…+650 °C
• Resolution: 0.1 °C
• Accuracy: ± 0.1 °C (probe error excluded)
• Sensor coefficient: a=0.00385 °C-1
• Connection: 2, 3 or 4 wires

Thermocouple

• Types: K, J, T, N, E. Inputs are not isolated: use thermocouples with an insulated hot junction.
• Ranges: type K: -200...+1370 °C; type J: -100...+750 °C; type E: -200...+750 °C; type T: -200...+400 °C; type N: -200...+1300 °C
• Resolution: 0.1 °C
• Accuracy (probe error excluded): type K: ± 0.1 °C (< 600 °C), ± 0.2 °C (> 600 °C); type E: ± 0.1 °C (< 300 °C), ± 0.2 °C (> 300 °C); type N: ± 0.1 °C (< 600 °C), ± 0.2 °C (> 600 °C); type J: ± 0.1 °C; type T: ± 0.1 °C

0/4...20 mA input

• Shunt resistance: internal (50 Ω)
• Resolution: 16 bit
• Accuracy: ± 2 µA

0…50 mV / -50…50 mV / 0…1 V / 0…10 V inputs

• Input resistance: 100 MΩ
• Resolution: 16 bit
• Accuracy: ± 0.01% f.s.

Counting inputs for potential-free contacts

• Switching frequency: 50 Hz max.
• Dead time: 10 ms min.

Potentiometer input

• Potentiometer: typically 10 kΩ
• Resolution: 16 bits
• Accuracy: ± 0.01% f.s.

Rain measurement

The logger can record the maximum rainfall rate, daily rainfall, total rainfall and the rain fallen during each logging interval.

Ordering codes

HD33[L]MT…. Weather station data logger with mobile communication module. It stores measurements in its internal memory and transmits the acquired data by FTP, by email or to an HTTP server (Cloud). Optional LCD display. SDI-12 and RS485 MODBUS-RTU Master or Slave connection. ETHERNET network connection with MODBUS TCP/IP protocol through an optional module. Alarm functions. Includes the HD35AP-S software, downloadable from the Delta OHM website. Battery, probes and the CP23 USB cable must be ordered separately; the SIM card is not included.

Accessories

• HD35AP-CFR21: advanced version of the HD35AP-S software for managing the data logging system in line with the FDA 21 CFR part 11 recommendations.
• CP23: direct USB connection cable with a male mini-USB connector on the instrument side and a male type A USB connector on the PC side.
• HD32MT.SWD: 100... 240 Vac / 24 Vdc (adjustable) power supply with switch, in an IP 65 housing suitable for mounting on a rod; mounting accessories included.
• BAT12V-3.4A: 12 V / 3.4 Ah rechargeable lead battery.
• HD2005.20: tripod kit with adjustable legs for installing environmental sensors (pyranometers, temperature and humidity, etc.), anodized aluminum, maximum height 2 m. It can be fixed with screws to a flat base or to the ground with pegs, and the legs fold for transport.
• HD2005.20.1: the same tripod kit, with a maximum height of 3 m.