Working calculation sheet. Enter measured loads and selected product data. Empty values remain unknown; totals are partial until every required field is entered. Values persist in this browser only; export to return them to the project.
Complete cable schedule · Electrical master
Design intent: 10 mm² positive and return, 4–5 m one-way. At a nominal 20°C copper resistivity of 0.0175 Ω·mm²/m, loop resistance is approximately 0.014–0.0175 Ω. Use actual STAR12 input current, not total unrelated rear-board loads.
This simple DC calculation omits terminal resistance and temperature correction. Final thermal sizing, voltage tolerance and fuse coordination remain engineering checks. Orion capacity reference: existing 48/12-30, 30 A nominal; verify thermal/installation derating.