We perform secondary injection testing of GFP systems for ECs and over the years (25-28) I have had countless GFP systems fail the initial test.
We test the GFP relay at all factor presets for current pickup and at a timed operation at the settings recommended in the coordination study (if supplied). We also test (megger) the neutral for any grounds downstream of the main service, megger the bus line and load and ductor/micro-ohm the power contacts. Lastly we recommended leaving the main line switch closed (as do manufactures) during construction till power is to be connected and recommended leaving the GFP relay set at minimum current and time delay for minimizing possible damage to equipment during construction.
Last edited by Brian_John; 01/19/09 05:02 PM.