Voltage Drop for Switchgear Controls

[faresos]

Hello everyone:

I'm working on a project that will require to provide external 48VDC for switchgear controls. The battery bank is about 200ft away and the load is about 43Amps at 48VDC. Based on 3% we will need #3/0 cables which I'm concern about if I can terminate this size in terminal lugs. My question is: What is the maximum voltage drop allowed for the DC system that will make the system operational?

Thanks,

 

[Julius Right]

My experience it is only with Power Stations. In my opinion, at first you have to double-check the list of DC consumers[including possible reserve for future extension] and to split the list in two parts:
one where all receivers are in operation all the time and the second for instruments acting for short time.
A 5% voltage drop-from rated-will be o.k. for continuous operation and 10% for sudden increased load.
ANSI T1 315 states that equipment shall operate properly for its intended service life with voltage variations between -42.0 Vdc and -56.7 Vdc measured at the first distribution point of the equipment. 42 V it will be 12.5% voltage drop.
IEC 60255 states the voltage limits 37.5 to 60 V for 48 V rated.