I am working as a tech for a power solutions company. For the last two years the scope of my work consists of connecting power quality analyzers (such as the Hioki 3169 or Fluke) to the load side copper pads of the main distribution transformer. This 3 ph transformer is intended to save energy and is tied to the client's bus bars just below the main breaker (near the CT compartment) before the main bus bars feed the risers so that it can actively effect the client's total consumption. In other words, these energy saving transformers are essentially a jumper cable between the main breaker and the client's main bus bars and it steps the voltage down from 600v to 575v.
I know it sounds dumb but I was young, green and hungry when I joined this company so I didn't think much of it and followed instructions. It has dawned on me recently that this work I'm performing live may not be safe? I always suit up with 1000v insulated tested gloves, balaclava, arc helmet with face shield, 12 cal/cm suite, and insulated boots. However, I have recently attended arc flash training ( a little late considering I'm two years in the field...employer decided it would be good for me as I raised a few concerns) and they taught us about reading the arc flash labels to ensure we choose the right ATPV level of PPE according to the incident energy level. Now that I know this, I have been keeping an eye out lately yet none of the transformers that I've worked on have these labels indicating the incident energy level nor the required ATPV. It only has a danger label stating that their is a shock/arc hazard. Mind you, these transformers are 347/600v and typically range from 500KVA-2500KVA. There was one site that surprisingly actually had this arc flash label on the client's switchgear and I kid you not, the main breaker that this transformer was tied too stated "108cal/cm". Now, the risers beside it were all rated at "3.1cal/cm" I'm guessing due to the C.B's protecting it.
I have received conflicting advice from electricians in the field.... one of our sub contractors stated that it is ok to proceed considering that these transformers are tied below the main breaker, his reasoning was that these main C.Bs or Fused disconnects would trip to stop the arc fault since the transformer is connected to it's load side. Moreover, he guessed that it would be in the vicinity of 3cal/cm if it is connected below the main breaker. This makes me feel comfortable as previously stated I'm wearing a 12 cal/cm suit.
However, another electrician was suggesting that it is actually not safe to proceed unless the incident energy level is known. He argued that due to the various KVA ratings from system to system each transformer would have a different incident energy level (makes sense to me). Also, he insisted that the incident energy level available is also based on the trip time settings of the main C.B or fused disconnects.
Now, I am at a standstill, and unsure if I should proceed with my day-to-day operations to test these live transformers or refuse the work completely. Ideally I would love to continue, considering that what I'm doing is deemed safe.
PS - these power quality analyzers utilize alligator clips and Rogowski CT's so there are no tools required for the connections. All of the work is done by hand with insulated gloves on of course.
I decided I would come here to ask the experts before I speak up to HR and sound like a diva if I'm wrong and over reacting...looking forward to all responses!