Analyzing the discharge activity requires the permanent installation of coupling devices. Preferably, such coupling devices are capacitive couplers terminated by a power separation filter.

Power Diagnostix standard coupling capacitors are mounted on sturdy cast aluminum enclosures and can be used for on-line and off-line measurements on rotating machines as well as for a variety of smaller test setups. A wider range of coupling capacitors and capacitor assemblies complete with quadrupoles and preamplifiers is available on request. The table to the right lists some standard models of coupling capacitors provided by Power Diagnostix, along with their built-in circuits, if present.

For areas exposed to explosion hazards Power Diagnostix offers the CC15A /Ex, a special coupling capacitor for Ex environments to prevent igniting of explosive atmospheres. The coupler can be used in hazardous areas in zone 2 for fixed mounted coupling of high frequency partial discharge signals with low energy.

The equipment is tested and approved for explosion hazard areas according to:

• Directive 2014/34/EU
• DIN/EN 60079-0
• DIN/EN 60079-15