Every circuit is checked against a percentage limit. Leave Crit unticked and the circuit is measured against the standard limit above. Tick it and the circuit is measured against the tighter critical limit instead.
Ticking Crit changes only the pass/fail threshold and the minimum section figure. The drop in volts is the same either way.
Tick it for circuits that stop performing properly when the voltage sags — anything vital to safety that needs close to full voltage to work as rated. Typically: navigation lights, bilge pumps, bilge blowers, and panel board main feeds. Leave it clear for general loads such as cabin lighting, sockets and accessories.
| Circuit | CurrentA | Lengthm, one-way | Cross-sectionmm² | Crittight | DropV | Drop% | Min. sectionmm² | Resultdrop only |
|---|
| Circuit | CurrentA | Lengthm, one-way | Cross-sectionmm² | Crittight | DropV | Drop% | Min. sectionmm² | Resultdrop only |
|---|
Voltage drop is only half of conductor sizing. A conductor that passes here can still be undersized once allowable current, insulation temperature rating, engine-space conditions and bundling derating are applied — and the governing constraint is whichever demands the larger section.
Run every circuit through the Electrical Calculator under Tools on www.ceinspector.com as well, and fit the larger of the two results.