We are installing a battery charger in a substation for batteries and need to run an AC cable to the charger. The charger is customizable in the sense that you could add up to 6 rectifier modules depending on the load, we will only use 2 rectifier modules and leave the remaining slots empty. We do not foresee any future load increases and will leave the remaining 4 slots empty. Each rectifier module draws a max current of 19A. The manufacturer installs a 80A AC breaker on the charger as a standard which is too big for our application since the maximum AC current drawn would be 19 X 2 = 38A. How should I size the cable and OCPD for the charger - should it be based on 19 X 2 = 38A? If so, the source breaker and cable would be much smaller than the breaker on the charger and that is where I am confused.
This will be a continuous load and I realize I will multiply the above current by 1.25 and apply any correction and adjustment factors to determine cable size and OCPD size.
This will be a continuous load and I realize I will multiply the above current by 1.25 and apply any correction and adjustment factors to determine cable size and OCPD size.