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Tank Gauging and Overfill Prevention etc.

2020 Analog Transmitter
2020 Analog Transmitter


2400 Analog Transmitter

The GSI 2400 Analog Transmitter is a current output (4-20 mA) transmitter that converts level measurement from a standard mechanical tank gauge.


Theory of Operation

The GSI 2400 Analog Transmitter is designed for simplicity of installation and calibration. The basic purpose is to convert the shaft rotation from the Magnetic Tank Gauge or Mechanical Tank Gauge into a 4-20 mA signal representing level.

It will mount directly to the GSI 2550 Magnetic Tank Gauge, GSI 2570 Mechanical Tank Gauge, or most manufacturers’ mechanical tank gauges. When coupled to the gauge output shaft the GSI 2400 utilizes the shaft’s rotation to turn a standard 10 turn potentiometer through a precision gear set. The potentiometer’s resistance value is then used to establish a variable amplifier gain and thereby derive a 4-20 mA signal.


The GSI 2400 Analog Transmitter offers features not found in other manufacturers’ units. We believe that it is the simplest, most reliable unit anywhere. All GSI 2400 Analog Transmitters feature:

  • An internal potentiometer coupled to a gear set through a clutch assembly. If the product level exceeds the maximum range, due to being out of calibration, the clutch assembly protects the transmitter from excess mechanical stress.
  • The GSI 2400 Analog Transmitter produces maximum output at or above the transmitter’s maximum range. This mode of operation is superior to other manufacturers’ units that reset to minimum value when the level exceeds maximum range. The advantage is that, if a transmitter is out of calibration, the GSI 2400 will consistently provide a 20 mA signal when the transmitter is at maximum regardless of product level.
  • The GSI 2400 Analog Transmitter uses 100% interchangeable precision gear sets, a common potentiometer, and a universal amplifier. Therefore, a transmitter ordered for a specific range can be converted to any other available range by simply replacing the gear set and reprogramming the hockey puck (software calibration).
  • The GSI 2400 uses only three major components which greatly simplifies repairs and reduces parts inventories.
  • The GSI 2400 is optionally available with Limit Switches.


The GSI 2400 may be ordered with an independent 20 mA temperature output. Two additional wires for field wiring are required, along with a separate RTD probe. The RTD provides the input for a separate 4-20 mA transmitter, and all voltage requirements are the same for both the level and the temperature transmitters. The RTD transmitter is mounted in the same housing and field wiring connections are made at the housing. The unit can be provided for use with either a copper or platinum RTD.



  • Liquid Level Measurement
  • Temperature Measurement
  • 4 SPDT Switches


Output:4-20 m Amps
Accuracy:0.4% of basic range
Temperature Range:
-25° to 160°F (-31.7° to 71°C)
Power:Loop or Externally Powered (2 or 4 wire)
8.5 to 60 feet (2.59 to 18.13 Meters)
Limit Switches:
1, 2, 3, or 4 Limit Switches
Materials:Cast Aluminum Housing, Anodized Internals, and Stainless Steel Trim
Voltage: 16-24 VDC, 24 VDC, or 115 VAC
Environmental:Class 1, Group C&D*
18 Awg instrument cable (2 or 4 wire)
Max Load:
1400 OHMS