I have an electrical upgrade I am doing. I am installation a diesel genset and replacing the cable from the existing pole mounted transformers to the transfer switch and from the transfer switch to the MDP. The transformer is existing so all I need to do is replace in kind these two power cable spurs.
The Power cable in question is the cable from the MDP to the subpanels. I expect that these cables are sized based on the calculated building loads for each subpanel and not the chosen transformer size. I know that my calculated building loads are different than what was calculated back in the 1950s when this cable was originally designed for and installed. I know my analysis is correct. I also know my task is not to rewire the whole facility, just install a diesel genset. I am replacing the secondary from the transformer since it is a short run and it makes sense to do it.
The cables from the transformer to transfer swtich and from the transfer switch to the MDP are sized based on the size of the pole mounted 3 phase transformer and its full load amps at the secondary, so no design work is necessary here if a new transformer is not being installed.
The Power cable in question is the cable from the MDP to the subpanels. I expect that these cables are sized based on the calculated building loads for each subpanel and not the chosen transformer size. I know that my calculated building loads are different than what was calculated back in the 1950s when this cable was originally designed for and installed. I know my analysis is correct. I also know my task is not to rewire the whole facility, just install a diesel genset. I am replacing the secondary from the transformer since it is a short run and it makes sense to do it.
The cables from the transformer to transfer swtich and from the transfer switch to the MDP are sized based on the size of the pole mounted 3 phase transformer and its full load amps at the secondary, so no design work is necessary here if a new transformer is not being installed.
