Field Data Loggers

Sigra provides the equipment to obtain data from nearly any application in any part of the world. The equipment may be purchased or hired. Sigra frequently supplies this equipment as part of a data acquisition service.

Sigra V10 Field Data Logger

Introduction

Sigra’s newest V10 field data logger may be used to collect and transmit data from a variety of sensors and devices.

The loggers will directly read many kinds of transducer including those with voltage or frequency outputs, vibrating wire transducers or resistance devices.

Multi-logger setups (supporting additional transducers) can be interconnected via an RS485 bus. These loggers can additionally be setup in a master slave configuration and take readings in turn.

Sigra V10 Field Data Logger

Loggers are able to communicate via radio. Radio communication is supported via plug in modules. The country of operation and or range required dictate which modules are employed. Options are available for the 920MHz or 2.4GHz ISM bands.

The loggers can be used to transmit to the outside world via any transmitter using an RS232 input. This includes, but is not limited to, high power radio transmitters or PSTN, 3G/4G or satellite data modems. Thus data can be acquired from virtually any location on the planet if one of these communications mediums are available.

The data transmitted may be acquired by the clients own data acquisition system, or generally and more conveniently, by Sigra who will collect and place it on the web for secure access by the client.

At Sigra, we can do more than just collect data. We can also check on the health of the field system remotely, process information, and  provide installation and service for the equipment.

The application for Sigra’s V10 Logger are vast. Field applications may include:

 

Examples of Use

The monitoring of a large landslide

Sigra has installed a monitoring  system on an area subject to landslide comprising a mass of igneous rock overlying sedimentary material. The contact has very low friction and moves continuously and at an increased rate when it rains and groundwater levels rise.

The monitoring system comprises multiple loggers in a network that collects rainfall, piezometric and pump operation information.

A 3G modem connected to one of the loggers in the network is used to remotely collect data from the networked loggers. This automated process is repeated several times each day. Sigra makes the data available to the client via a secure web server. To reduce the amount of data the client has to review, the loggers are configured to record only when data changes by more than a set amount. A heartbeat record at a longer interval is still recorded to reassure system integrity.

Reservoir monitoring

The Sigra loggers are frequently used to monitor pressures in coal seam gas reservoirs. In this case they generally monitor multiple transducers, cemented into a well.  At surface is a box containing loggers that are coupled via RS485 and communicate to the outside world via a modem.  The units are powered by a solar cell which stores energy in batteries.

Details

Sigra’s Field Data Logger is a low power, versatile, eight channel device designed to monitor several types of sensors:

  • Vibrating Wire
  • Voltage
  • Frequency
  • Resistance (Thermistors)
  • Switches (Reed Switch, Rain Gauge, Flow Meter)

Communication with the logger can be achieved by:

  • Direct cable to PC (USB or RS232)
  • Data modem (any modem with RS232 port)
  • Logger to Logger radio or RS485 (or both) network

The radio modules operate in the ISM bands. Please contact Sigra for advice when choosing radio modules.

Windows based software allows the setup and downloading of the data logger via any communications interface.

The Sigra Data Logger V10 comes with a 32 GB micro-SD card built-in to permit lifetime storage.

The internal clock chip with a built-in crystal oscillator has a time drift of less than 2 minutes a year across the full operating temperature range. Less than 20 seconds of drift is achievable if maintained between 10 and 40 degrees Celsius.

The V10 Data Logger (IP65 version) now has a built-in Low Voltage Disconnect (LVD) to protect the batteries from extreme discharge. This prevents the early failure of cells.

Specifications

Channels

  • 8 Channels for Voltage, Resistance and Frequency.
  • 4 may be used for Vibrating Wire (Odd Channels).
  • 4 may be used for Counting Inputs (Even channels).

Range and Resolution

  • Vibrating Wire:
    • Range: 0.5 – 5 kHz
    • Resolution: 0.01 Hz
    • Raw unit: 0.1 Hz
  • Resistance:
    • Range: 0 – 330 kΩ
    • Resolution: 1 Ω
    • Raw unit: 1 Ω
  • Voltage:
    • Range: 0 – 5 V (Use an external potential divider for higher voltages)
    • Resolution: 77 µV (16 bit)
    • Raw unit: 77 µV
  • Radio:
    • Frequency: 2.4 GHz ISM Band or 920 MHz
    • Transmit Power: 63mW and 250 mW respectively
    • Reliable range: 0.6 km and 2.5 km respectively – dependent on local conditions and topography

Battery

Rechargeable battery with solar panel for weatherproof enclosure.

Environmental Rating

  • DIN Mounting: IP20
  • Weatherproof enclosure: IP65

Software

Compatible with Windows XP, Vista, 7, 8, 10