GT420, GT422 and GT423 Marine Differential Pressure Transmitters

The GT420, GT422 and GT423 are differential pressure transmitters designed for general purpose use in maritime and offshore applications. A differential pressure can be measured between two points on independent systems or between two different points.

Key features

• Accuracy of 0.25 % FRO
• Low long-term drift
• Pressure ranges up to 25 Bar
• Single element design
• Excellent overload capacity
• HART compatible
• Body of AISI 316
• Rugged construction
• Ex certification II 1 G Ex ia IIC T5

Typical applications

• Hydrostatic level measurement of a tank's content, where the gas of the top of the tank is not vented
• Leakage monitoring by measuring the difference in pressure between a controlled reference pressure and the component under test pressurised to the same pressure
• Density measurement of a fluid where a reference height indirectly gives the density
• Filtration monitoring where the difference between upstream and downstream indicates the contamination of the filter

Transmitter are available with pressure ranges up to 25 bar. Standard zero point is 0 bar differential (4 mA output), but other options are available.

Mechanical design

Each transmitter consists of a sensing element with a signal converter unit encapsulated in a body made of stainless steel, AISI 316.

Three different connections are available.

• DIN EN 17301 power connector
• Connection box with cable gland
• Flanged for watertight connection

Electrical connection

The pressure transmitter require connection to a 24 VDC power supply, and provide 2-wire connection with 4-20 mA current loop output. A screened cable must be used from the transmitter to the monitoring system for GT420 and GT422. A dedicated PUR cable with a flange connection must be used for GT423.

Mounting and installation

Kongsberg Maritime can deliver detailed installation instructions and necessary installation material for various installations. Please ask for documentation according to applications.

Power supply

Power supply to the transmitter is 24 VDC nominal, and can vary from 12 to 32 V. As an Ex transmitter it's restricted to 28 VDC. The allowable load is determined by the minimum power supply.

Intrinsic safety

Electrical connection in hazardous areas has to be through a Zener barrier, i.e. the Kongsberg DZ-110 Transmitter Barrier.