HIGH VOLTAGE DC DIELECTRIC TEST (HVC)

(HIPOT)

The (HVC) High Voltage DC Dielectric Test Sets(40,50 and 60kv) Provide the most dependable portable dc high voltage sources for checking the quality of electrical power cables, vacuum switch, motor, switchgear, insulators, transformers and capacitors.Lightest weight available in compact high voltage model.Designed for maximum operator safety.

Description
The (HVC) High Voltage DC Dielectric Test Sets(40,50 and 60kv)Provide the most dependable portable dc high voltage sources for checking the quality of electrical power cables, vacuum switch, motors, switchgear,    insulators ,transformers and capacitors, Each portable set is comprised of two separate modules.

Control Module
This module allows the operator to switch select the appropriate voltage output range, adjust the output level and monitor both the applied voltage and leakage current at a safe distance from the high voltage being delivered to the load under test.

High Voltage Module
A High voltage module receives its instruction from the control unit. It generates the dc high-voltage that is delivered to the load under test. Each high voltage module is a different size and weight to accommodate the rated output voltage.

Applications
The family of HVC dc dielectric test sets is used to make proof tests and insulation tests on electrical power cables, motors, switchgear, insulators, transformers and capacitors.Both type of tests are performed by applying controlled high voltages to the unit under test at or above insulation system operating level.
Measuring the leakage current helps determine the unit under test’s ability to withstand over voltages such as lightning strikes and switching surges.
The four models described cover a range of output voltage that meet the most commonly specified rating in 5kv to 69kv class cable. All are suitable for testing power cable, switchgear and rotating machinery in accordance with IEEE, NEMA and ANSI guidelines.

Proof Test
Proof testing is used for acceptance testing of newly installed cable and maintenance testing of aged and/ or repaired cable.For the proof test, the unit under test will either withstand the test voltage or it will “break down” providing the user with a “go/no go” answer. This is essentially the same as the proof test performed by impulse generator systems (within voltage limitations).

Insulation Resistance Tests
To make appropriate insulation tests on healthy insulation, the test instrument must have microampere sensitivity insulator resistance can be measured in at least three different ways .The insulation resistance test is often referred to as a “spot check”, and is performed by applying a predetermined voltage to the unit under test, holding it until the apparent leakage current becomes stable and recording the readings with adjustments for temperature. This test is especially applicable to low capacitance units under test. Time varying tests such as the polarization index test (PI test) are independent of temperature effects and save time. To perform the PI test, a predetermined test voltage is applied to the unit under test and readings are taken at 1 minute and 10 minutes. The resulting ratio is analyzed to determine insulation quality. This type of test is especially appropriate for high capacitance samples.The step voltage test is independent of temperature effects and save time. To perform this test, the output voltage  is increased in even steps at regular intervals over a fixed period of time. As long as the resistance of the unit under test increases with time, it has high quality insulation. This type of test is only useful for high capacitance samples.