ANSI EIA-364-44A-1998 pdf download Corona Test Procedure for Electrical Connectors
1.2.3 Corona inception voltage (CIV) The lowest voltage at which continuous corona occurs as the applied voltage is gradually increased. For a sinusoidal alternating applied voltage, the CIV is expressed in volts rms (0.707 times the peak voltage).
1.2.4 Corona extinction voltage (CEV) The voltage at which continuous corona is no longer evident as the applied voltage is gradually reduced from the corona inception voltage. For a sinusoidal alternating applied voltage, the CEV is expressed in volts rms (0.707 times the peak voltage).
2 Test equipment
2.1 The corona extinction voltage shall be measured with commercial corona test equipment or with a suitable test circuit having the required sensitivity. An example of a suitable circuit shown in figure 1 together with the formula for determining the sensitivity of the circuit shown. Unless otherwise specified, the deflection sensitivity of the oscilloscope presentation in the test circuit shall be 5 pC/cm (picocoulombs per centimeter). Most commercial corona test equipment will have a minimum sensitivity of 1 pC/cm.
2.2 There are two types of data display systems utilized. Older systems will utilize an oscilloscope display. Currently available commercial corona test equipment is usually used in conjunction with a multichannel analyzer or also referred to as a pulse height analyzer (PHA), this is the recommended data acquisition and display method. Along with the ability to acquire the total number of occurrences and pC levels of each occurrence, some PHA systems also have the ability to manipulate acquired data to provide picocoulombs/second data. Since a PHA provides quantitative data it may be used for all types of testing, offering a dynamic range in excess of 100 pC with a sensitivity of 1 pC minimum. An oscilloscope system is best suited for testing for moderate to high levels of corona where quantitative data is not required. Oscilloscopes systems are typically a compromise between good sensitivity and good dynamic range.
2.3 The test voltage supply shall be free of self-generated partial discharges and other sources of spurious interference signals, including power line noise, throughout the test range, to a level well below the sensitivity of the detector. For testing that requires highly sensitive measurements, it is recommended that the test equipment and power supply be located in an electrically shielded room.