Loop Resistance Test: R = R + R + R loop C.T LOAD LEAD Calculated Burden = I2 * R LOOP R Phase – Measured Measured Calculated No Core Burden (VA) R (Ω) C.T RLoad + Rlead(Ω) R Burden (VA) loop(Ω) 2000-3000/1A -- CT1-1 1S1 1S3 – CT1-2 2S1 2S3 2000-3000/1A -- – 2000-3000/1A -- CT1-3 3S1 3S3 – 2000-3000/1A -- CT2-1 1S1 1S3 – 4000/1A -- CT2-2 2S1 2S2 – 4000/1A -- CT2-3 2S1 2S2 – Y Phase – Measured Measured Calculated No Core Ratio Burden (VA) R (Ω) C.T RLoad + Rlead(Ω) R Burden (VA) loop(Ω) 2000-3000/1A -- CT1-1 1S1 1S3 – 2000-3000/1A -- CT1-2 2S1 2S3 – 2000-3000/1A -- CT1-3 3S1 3S3 – 2000-3000/1A -- CT2-1 1S1 1S3 – 4000/1A -- CT2-2 2S1 2S2 – 4000/1A -- CT2-3 2S1 2S2 – B – Measured Measured Calculated No Core Ratio Burden (VA) R (Ω) C.T RLoad + Rlead(Ω) R Burden (VA) loop(Ω) 2000-3000/1A -- CT1-1 1S1 1S3 – 2000-3000/1A -- CT1-2 2S1 2S3 – 2000-3000/1A -- CT1-3 3S1 3S3 – 2000-3000/1A -- CT2-1 1S1 1S3 – 4000/1A -- CT2-2 2S1 2S2 – CT2-3 2S1 2S2 4000/1A -- – All temperatures at what resistance measured should be recorded and all resistances referred to the value at 75° C.
Loop Resistance Test: R loop = R C.T + R LOAD + R LEAD Calculated Burden = I2 * R LOOP R – Phase No Core Burden (VA) R C.T (Ω) Measured RLoad + Rlead(Ω) Measured R loop(Ω) Calculated Burden (VA) CT1-1 1S1 – 1S3 2000-3000/1A -- CT1-2 2S1 – 2S3 2000-3000/1A -- CT1-3 3S1 – 3S3 2000-3000/1A -- CT2-1 1S1 – 1S3 2000-3000/1A -- CT2-2 2S1 – 2S2 4000/1A -- CT2-3 2S1 – 2S2 4000/1A -- Y – Phase No Core Ratio Burden (VA) R C.T (Ω) Measured RLoad + Rlead(Ω) Measured R loop(Ω) Calculated Burden (VA) CT1-1 1S1 – 1S3 2000-3000/1A -- CT1-2 2S1 – 2S3 2000-3000/1A -- CT1-3 3S1 – 3S3 2000-3000/1A -- CT2-1 1S1 – 1S3 2000-3000/1A -- CT2-2 2S1 – 2S2 4000/1A -- CT2-3 2S1 – 2S2 4000/1A -- B – No Core Ratio Burden (VA) R C.T (Ω) Measured RLoad + Rlead(Ω) Measured R loop(Ω) Calculated Burden (VA) CT1-1 1S1 – 1S3 2000-3000/1A -- CT1-2 2S1 – 2S3 2000-3000/1A -- CT1-3 3S1 – 3S3 2000-3000/1A -- CT2-1 1S1 – 1S3 2000-3000/1A -- CT2-2 2S1 – 2S2 4000/1A -- CT2-3 2S1 – 2S2 4000/1A -- All temperatures at what resistance measured should be recorded and all resistances referred to the value at 75° C.
ct_loop_test.docx