Push the “Test” button on the meter and after one minute observe the resistance reading. Set the meter to 1000 Volts or pre decide DC Voltage. Attach the high voltage lead to one of the isolated circuit phase conductors. Connect the ground lead of the HIPOT Tester to a suitable building ground or grounding electrode conductor.(1.53m) so place barriers around the terminations of cables and equipment under test to prevent unqualified persons from crossing this boundary. The limited approach boundary for this hi-pot procedure at 1000 volts is 5 ft. Confirm that all equipment or Cable that is not to be tested is isolated from the circuit under test.Open circuit breakers or switches to isolate the circuit or Cable that will be hi-pot tested.Only electrically qualified workers may perform this testing.Therefore, the current of interest is the current that is the result of a partial discharge or breakdown, rather than the current due to capacitive coupling. Although this small current is acceptable, no breakdown of either the air insulation or the solid insulation should take place. If the insulation between the two is adequate, then the application of a large voltage difference between the two conductors separated by the insulator would result in the flow of a very small current. Testing a contact in this fashion makes sure it is isolated from all other contacts. When you have more than two contacts to be hipot tested you connect one contact to high voltage and connect all other contacts to ground. With the supply connected like this there are two places a given conductor can be connected: high voltage or ground. The other side of the supply is connected to the conductor being tested. Hipot testers usually connect one side of the supply to safety ground (Earth ground). The reason for using 1000 V as part of the basic formula is that the insulation in any product can be subjected to normal day-to-day transient over voltages.Įxperiments and research have shown that these over voltages can be as high as 1000 V. Other examples include identifying a pinhole defect in insulation or finding an enlarged solder footprint.Īs per IEC 60950, The Basic test Voltage for Hipot test is the 2X (Operating Voltage) + 1000 V HIPOT test is applied after tests such as fault condition, humidity, and vibration to determine whether any degradation has taken place. Inadequate creepage and clearance distances introduced during the manufacturing process. Hipot tests are helpful in finding nicked or crushed insulation, stray wire strands or braided shielding, conductive or corrosive contaminants around the conductors, terminal spacing problems, and tolerance errors in cables. This is a high-voltage test that is applied to all devices for a specific time in order to ensure that the insulation is not marginal. The hipot test is a nondestructive test that determines the adequacy of electrical insulation for the normally occurring over voltage transient. Hipot test is the opposite of a continuity test.Ĭontinuity Test checks surety of current flows easily from one point to another point while Hipot Test checks surety of current would not flow from one point to another point (and turn up the voltage really high just to make sure no current will flow). Hipot test makes surety of no current will flow from one point to another point.
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