Comparison to Manufacturers' Standards

Click here to get more information on how other cable tests compare to the rigors of the cable and accessory manufacturers' standards

The Factory GradeSM Test

IMCORP's unique offering is the Factory GradeSM test. IMCORP tests cable systems installed in the field in the same manner as the manufacturers quality control the components in the factory. This is the only way to ensure that the system components will meet their design life.

Comparability to the manufacturers' test is not a simple matter. There are several key aspects to this test, without any of which it is simply not factory grade.

 

Quality Control Specifications of Cable & Accessory Manufacturers

IMCORP performs Partial Discharge (PD) tests at Power Frequency

The manufacturers’ standards require that you energize the cable with 50 or 60Hz AC power to activate defects so they are observable during the test. Testing at power frequency allows us to observe cables systems under the same conditions at which they will be operating.  Rise and fall times of the AC signal is a direct factor in PD inception (turn on) and extinction (turn off). Competitive solutions test at .1-1Hz  (deviating from power frequency by a factor of 60-600) and are unlikely to create PD events as they would happen under operating conditions.

 

IMCORP energizes cable systems above operating voltage

The manufacturers' standards require that you test for PD activity well above the operating voltage (Uo). This is in recognition that only gross errors in manufacturing or installation will appear at operating voltage, and significant risk to system reliability still exists in PD sites which activate above Uo.

 

IMCORP performs standardized pre-test calibration

The manufacturers' standards require that you calibrate and assess the sensitivity of the equipment for each cable test. These steps ensure that the test will detect 5pC partial discharge signals. It is well documented that even large defects in cable systems can sometimes emit such small pulses, so if this step is omitted you risk missing defects posing grave danger to your system reliability.  Most commercially available PD systems are non-calibrated systems and cannot see any activity below 50-100pC in the field.

 

IMCORP's system provides background noise removal

Background noise removal is an essential factor in discerning PD signal patterns. Our multi-stage filtering allows us to remove and lower baseline noise frequencies. This aspect of our process allows us to pick out real quantifiable PD events where competitive solutions simple see what they can see.