Deltawhy, Your last post was correct. You've stumbled onto one of the means to determine magnetizing impedance - the open circuit impedance test, primary side. I would bet that your old welder is an autotransformer type.
The part of your question that concerns me is that you do not indicate the value of the the short circuit current computed at the beginning of the bus run; you only mention the end of the run which I understand to be at the point of the longest length. A fault near the beginning will be...
There are a number of good references. To start, I recommend "
Standard Handbook for Electrical Engineering" by Fink and Beatty. Also consider "The Electrical Engineering Handbook" by Dorf. The best set to consider that are more specific to power and industrial engineering are from IEEE. The...
Limiter lugs are intended to protect the cables from short circuit damage. The do not reduce fault current; however, the clear quickly when subjected to a high fault current. They may not operate in their current-limiting range if the fault current is a lower level fault as is sometimes the...
If the equipment is going to require "examination, adjustment, servicing, or maintenance while energized", then it will require the working space described in 110.26 (A). Being on casters, I presume it will can be de-energized by a plug or disconnect means, so it would not require the working...
There is no limit to imbalance; however, each conductor must have the ampacity and overcurrent protection for the load it will carry (Article 240.4). The other code concern for imbalance is in Article 392.8 (D) where it is possible that currents may not be balanced in paralleled sets if their...