Partial discharge (PD) measurements are a proven method for effective, nondestructive evaluation of electrical insulation.
The Power Diagnostix ICMcompact provides a simple push-button interface and on-screen menus in an embedded LCD panel. The LC display modes include a simple PD charge meter with adjustable “needle” sensitivity, monochrome phase-resolved PD patterns for classificationof defects, and a scope-like display showing phase summed charge pulses superimposed with the applied voltage wave. Although the ICMcompact is an autonomous unit, it can be connected to a computer installed with Power Diagnostix software to capture screenshots or to implement remote control of the unit.
Instantly displaying information in an intuitive interface, the ICMcompact is a good choice for applications such as quality control tests in manufacture of electrical products and for quality assurance of industrial and utility equipment; from capacitors and bushings to gas-insulated switch gear, voltage transformers and others. A wide range of accessories adapts the ICMcompact to specific testing applications and noise conditions.
The ICMcompact DSO option can be used to locate partial discharge defects in power cable. Using time domain reflectometry, in which the PD and its “echoes” travel the length of the cable under test, the ICMcompact provides the proportional distance of the PD fault along the cable.
Generally, this unit can be used with the full range of the ICM series preamplifiers, covering the IEC 60270 standard frequencies.
ICMcompact with PD Spectrum Analysis (SPEC Option)
Observing the frequency spectrum of a harshly disturbed PD signal allows selecting frequency bands with fewer disturbances. Using this selected frequency for a PD acquisition gives a largely improved signal-to-noise ratio resulting in a clear pattern acquisition. The combination of spectrum analyzer and PD detector within one instrument opens a broad field of new possibilities when analyzing isolation defects even with large noise.
The ICMcompact can be equipped with one, three or eleven channels. A multiplexer allows to directly select the input signal.
The SPEC mode shows the frequency spectrum of the input signal with a selectable span of up to 10 MHz. Three spectrum traces of the current input channel can be stored, compared, and analyzed. A variable cursor serves to set the center frequency for the PD pattern acquisition.
To adapt the basic ICMcompact unit to suit special measurement requirements, it can be equipped with various options:
- Voltage measurement. Adds the HVM oscilloscopic display showing the wave form of the high voltage and calculates Û, Û/√2, Urms, etc.
- Cable fault localization. An additional DSO board samples the PD signal at 100 Msample.
- Analog gating to cancel external disturbance. This option offers sensitive measurements even in noisy environments.
- MUX4. Four-channel multiplexer for testing three-phase equipment, such as power transformers. For each channel the unit maintains an individual setup and calibration.
- MUX12. This option offers a built-in 12-channel multiplexer or a remote 12-channel switching box for acceptance testing on large power transformers.
- AUX4. For long-term testing up to four additional parameters can be captured as 0(4)-20 mA or 0-10 V signals.
- RIV measurement. Adds a radio influence voltage measurement function to the instrument (needs the SPEC option and includes the MUX4 option).
- Modem. Allows communication with the instrument via analog telephone line.