My AccountLogin +


Current Transformers

The Power Diagnostix line of coupling devices includes quadrupoles, current transformers, and coupling capacitors to adapt Power Diagnostix PD detectors to different measurement tasks. The coupling device in a PD measuring circuit provides the means of sensing the partial discharge pulse and sending it as a voltage signal to a preamplifier for conditioning.

Current Transformers

When a current transformer is used instead of a quadrupole, the current transformer can be placed around a coupling capacitor terminal or around a part of the test object itself. A current transformer has the advantage of providing galvanic isolation between the ICMseries PD detector and the high voltage circuit. Power Diagnostix offers current transformers as separate modules or integrated with a coupling capacitor into a single unit.

The CTs are a low-impact PD sensor option since no interruption of the power connection is required. Such installation is even possible under on-line conditions, as the CT100 is a clamp-on current transformer that can be opened and clamped around a connecting cable, a ground lead, or even a feeding medium-voltage cable with a high-voltage motor installation.

Standard Sizes

Type Transfer Ratio at 50 Ω Primary Window Bandwidth at -3 db Bandwidth at -6 db
CT1 1:10 15 mm 0.5-80 MHz 0.3-100 MHz
CT100(/R) 1:10 100 mm 2-25 MHz 1.2-40 MHz
CT125R 1:10 125 mm 2-25 MHz 1.2-40 MHz
CT150R 1:10 150 mm 2-25 MHz 1.2-40 MHz