Illustration only. The default numbers are invented, not from any utility map. This is our own simple reading rule, not a utility rule: the utility's screen and study decide. Enter kW AC (1 MW = 1,000 kW). Check your map for its own units.
Method: net headroom = map value minus queued kW that the map does not already count (never below 0). Margin = net headroom minus the proposed system. If you enter a second value for the other end of a line section, the result is shown for both ends. A passing result is not an approval: protection, secondary-network and site-specific checks are outside most maps.