Sizing a Chassis Ground for My Victron Inverter/Charger?

Question:

Great content. So happy I found your website and information. I am trying to finalize the installation of my Victron 12/3000 Inverter/Charger and am working through the chassis ground. Your information states the appropriate size is "at most one size less than the AC/DC input cables". The 12/3000 suggests two 1/0 cables for each of the DC lines (positive and negative). So chassis ground is 3/0, since two 1/0 is equivalent to a single 4/0. Does this sound right? - Mark

Answer:

You are correct that the chassis ground must be one size smaller than the current-carrying conductor and 3/0 should be used. If you are specifically buying 3/0 for this purpose there is nothing wrong with installing dual 1/0 cables to be the same size for the chassis ground, the “one size smaller” rule is stated as a minimum.