■ GDT.855, SF₆ Gas Density Monitor

- Dedicated software for SF₆ gas temperature compensation

- Up to 4 micro-switches available (SPDT contacts)

- High switching accuracy and long-term stability

- Maximum measuring range: 0…11 bar abs.

- Various axial / radial process connections available

- High shock resistance

 

■ Product Overview

The GDT.855 is a gas density monitor designed to monitor SF₆ gas density and condition in high-voltage power equipment.

Using a sealed bellows chamber filled with reference SF₆ gas and a pressure sensor, it continuously measures and monitors changes in SF₆ gas density as temperature varies.

Dedicated temperature compensation software corrects the switching output for temperature changes, providing high switching accuracy and long-term stability.

Up to four micro-switches can be configured, with various process connections and mounting orientations available to suit equipment requirements.

The product is designed for SF₆ gas density monitoring, high-voltage circuit breakers, and gas-insulated power equipment.

■ Applications

▶ SF₆ Gas Density and Condition Monitoring Systems

▶ High-voltage Circuit Breakers

▶ SF₆ Insulated Busbar Systems

▶ Gas-insulated Substations (GIS)

■ Key Performance and Configuration Options

▶ Switching setpoint accuracy: ≤ ±10 kPa @ 20°C

▶ Temperature accuracy: ≤ ±1°C

▶ Micro-switches: 1–4 available (SPDT changeover contacts)

▶ Measuring units: bar / MPa / kPa / psi / kgf/cm²

▶ Dial color indication: Green / Yellow / Red

▶ Cable gland: M20×1.5 (selected according to cable outer diameter)

▶ Process connection orientation: Axial / Radial (Radial: Bottom / Left / Top / Right)

■ General Specifications

Measuring Range	0…11 bar abs. (maximum range)
Monitoring Principle	Absolute pressure measurement using a sealed bellows filled with reference SF₆ gas
Switch Contacts	1–4 micro-switches / SPDT (changeover)
Switch Rating	AC 250 V / 6(2) A (resistive load)
Switching Accuracy	≤ ±10 kPa @ 20°C
Temperature Accuracy	≤ ±1°C
Temperature Compensation	-20…+60°C
Electrical Connection	Cable gland M20×1.5 / IP67
Process Connection	G1/2 male / M20×1.5 male / swivel nut / fitting / flange, etc.
Installation Direction	Axial / Radial (Bottom / Left / Top / Right)
Material	Body & connection: Stainless Steel 316L Housing: Aluminium