Advanced Industrial

shield sdi12 4-20mA pulse counter

Scope

Provide support for SDI-12, 4-20mA and pulse counter sensors with flexible configurations. It is applicable to Agriculture & Environmental Monitoring applications.

General Information

Host board insigh.io main board
Supported Digital Interfaces 2 x SDI-12 & 2 x 4-20mA & 1 x Pulse Counter
Sensor Headers Fixed Terminal Block with push-in connection (no tools required)
1x8-pin (SDI-12 & Pulse Counter) & 1x6-pin (4-20mA)
Dimensions (L x W x H) 41.3 x 47 x 16.7 mm
Weight 16 g

Example Applications

  • Precision Agriculture
    • Soil moisture, Electrical Conductivity, Volumetric Water Content, Temperature
  • Environmental monitoring
    • Water flow, water quality, Temperature, Humidity

Sensors Support (Hardware & Software)

SDI-12 Interface

Number of Supported Sensors Up to 2 (simultaneously), 3 pins (POWER,DATA,GND) each
Up to 9 if external combiner is used
Supply Voltage 12V DC (external power supply may be used as well)
Maximum Drawn Current 1A
Sensor models sw support General SDI-12 Commands Implementation
Fully tested against the following models: TEROS-12 (METER) & TDR-315H (ACCLIMA)
Advanced Features Resistors R7,R10,R3 for controlling “power” mode
Jumpers J5 & J6 for controlling “measurement” mode

4-20mA Interface

Number of Supported Sensors Up to 2 (simultaneously) / 2-wire or 4-wire
Supply Voltage 12V DC (external power supply may be used as well)
Maximum Drawn Current 1A
Sensor models sw support Sensor-agnostic, using a 2-channel analogue current sensing circuit
Fully tested with HAITRONIC 4-20mA 4-wire Digital Signal Generator Module Board)
Advanced Features Jumpers J3 & J4 for controlling “measurement” mode

Generic Digital Interface

Number of Supported Sensors 1
Supply Voltage No, the sensor should be externally powered)
Typical Usage Pulse Counter (feature not supported yet in firmware)
Advanced Features Jumpers J7 for controlling “measurement” mode

Advanced Features

“Power” mode

There are 2 “power” modes for both SDI-12 and 4-20mA controlled via the PCB hardware & firmware:

  • “Heating” mode (default): It applies continuous 12V DC. This is required by some sensor for condensation avoidance (e.g. Oxygen Sensor SO-411 from Apogee). It is enabled through mounting R7 (1K) and not mounting R10 (0 Ohm) & R3 (1M).
  • “Low-power” mode: This is a mode optimized for energy consumption. To select this mode remove R7 (1K) and mount R10 (0 Ohm) & R3 (1M). In this mode, the sensors are powered only during the micro-controller wake-up periods by enabling a special control pin from the firmware, i.e. IO37.
“Measurement” mode

In addition, with the use of Jumpers the user may control the “measurement” mode. There are 5 jumper sets:

  • J5 & J6 controls the SDI-12 Sensor Port 1 and 2 respectively
  • J3 & J4 controls the 4-20mA Sensor Port 1 and 2 respectively
  • J7 controls the single Digital Port The operation is controlled as follows:
  • If jumpers enable the “always-on” mode (left-center pins), then the sensor data can be accessed continuously.
  • If jumpers enable the “on-demand” mode (center-right pins), then the sensor data can be accessed only when the proper control pin is enabled. This is the most power-efficient mode. The control pins are:
    • SDI-12 Sensors: IO42 & IO48 for Port 1 & Port 2 respectively
    • 4-20mA Sensors: IO7 & IO8 for Port 1 & Port 2 respectively
    • Pulse Counter Sensor: IO6
4-20mA Sensors Connection Instructions

Below you may find the proper connection instructions for 2-wire/4-wire sensors in case internal (own board) or external power supply unit is used:

  • Sensor Type: 2-wire

    • Power Supply: Internal
      • Sensor PWR pin connected to VIN board port
      • Sensor OUT pin connected to OUT board port
    • Power Supply: External
      • Sensor PWR pin connected to External Supply Positive Pin (+)
      • Sensor GND pin connected to External Supply Negative Pin (-)
      • Sensor OUT pin connected to OUT board port
  • Sensor Type: 4-wire

    • Power Supply: Internal
      • Sensor PWR pin connected to VIN board port
      • Sensor 1st GND pin connected to GND board port
      • Sensor 2nd GND pin connected to same GND board port
      • Sensor OUT pin connected to OUT board port
    • Power Supply: External
      • Sensor PWR pin connected to External Supply Positive Pin (+)
      • Sensor 1st GND pin connected to External Supply Negative Pin (-)
      • Sensor 2nd GND pin connected to GND board port
      • Sensor OUT pin connected to OUT board port

Marking

CE planned
FCC planned
RoHS planned

Custom designs

The existing boards are highly configurable and expandable so if the existing boards do not fit your need, get in contact with us and we will tailor a solution for you with your customizations.