nobody has mentioned the new amprobes that go around both conductors, or the ideal circuit testers here that would suffice
Or possibly going to the first available j-box above the ceiling and taking the reading there,After all, we are talking commercial and there is most likely a box right above the stub up from the receptacle
Please read my last post. I will contact a licensed electrician if need be. For now, there is NO need to. I will call him I need to be intrusive these ckts. As for now, the flexiclamp by Megger will work just fine.