What is the consensus regarding the testing of variable fault interrupters (VFI)?

Our shop was having a discussion regarding the testing of a VFI today, and it brought up a good question. NETA does not have a section for VFIs so our guys will test them as medium volt vacuum/SF6 switches. The disagreement comes when talking about the fault interruption system. Some say you should test the controller either by primary injection to test the CTs/times & pickups, or testing of relays such as a SEL 751. Some say since its not in NETA, its not a requirement to test the controller at all. What do you think and why?

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