Insulation testing Preliminary lead check Inspect the test leads Select the

Insulation testing preliminary lead check inspect the

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Insulation testing Preliminary lead check Inspect the test leads Select the correct range where necessary Insulation testing Firmly connect the test leads across the circuit under test Operate the instrument according to manual Take the reading directly from the display Stop operating the instrument before disconnecting the leads
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Insulation resistance reading Apply the test voltage for 1 min for the reading to drop or remain relatively steady. Record the resistance value
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Safety precautions for insulation and continuity testers Read the specific operation instructions for the instrument The circuit under test must be dead The circuit MUST not be touched during an insulation resistance test Test leads and crocodile clips MUST be in good condition The leads should be clean and with no broken or cracked insulation
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Insulation resistance test on a transformer Insulation resistance test is conducted on transformers to verify the integrity of insulation between the windings/earthed parts The test is conducted when the transformer is Isolated The transformer body earth should not be removed Insulation tests on transformers comprise of three parts HV winding tested to the LV and earth LV winding tested to the HV and earth HV winding tested to LV winding
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HV winding tested to the LV and earth For transformers ≥ 66 KV use 2.5 KV D.C For transformers < 66 KV and LV circuits use 1.0 KV D.C Minimum acceptable insulation resistance R min = 2Y + 2 MΩ Where Y Is The Higher Voltage Rating Of The TX In Kv Do not apply a higher voltage than the recommended as there is risk of damaging the insulation.
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Transformer Insulation Resistance test
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Transformer Testing
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Transformer Testing
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Insulation resistance test to a cable
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Insulation resistance test to a cable
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  • Spring '18
  • Professor Obura Oluoch
  • special attention, continuity tester, Safety Warnings

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