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Electrical tools
Sizing a circuit is one connected decision, not five separate lookups. These tools follow the run from the load through the wire, the breaker, the conduit, and the box, and tell you what is really driving each size.
Electrical Wire Size and Voltage Drop Pick a conductor size and material for a run, and know whether ampacity or voltage drop is really driving it. Electrical Breaker and OCPD Sizing Size the breaker for a load and its conductor, and see what the code rules actually require. Electrical Motor Circuit Sizing Size the conductor, overload, and branch protection for a motor from its horsepower and voltage. Electrical Ampacity Derating Adjust conductor ampacity for ambient temperature and bundled conductors, and see if the wire still carries the load. Electrical Grounding and Bonding Sizing Size the equipment grounding conductor by breaker, or the grounding electrode conductor by service size and electrode type. Electrical Backup Generator Sizing Size a backup generator for the loads you want to run, and compare essential, whole-house, and load-managed options. Electrical Service Load Calculation Estimate a dwelling service or feeder size with the NEC Article 220 standard method, as a planning sanity check. Electrical Transformer kVA Sizing Size a transformer in kVA from the connected load, phase, and voltages, with FLA and NEC primary protection. Electrical Voltage Drop Remedy Your run drops too much voltage. See the ways to fix it and which one makes sense. Electrical Conduit Fill Pick a conduit size for a bundle of conductors and see how much room is left for future pulls. Electrical Box Fill Figure the required box volume for your conductors and devices, and pick a box that fits. Electrical Conduit Bending Offset Lay out a conduit offset: distance between bends, shrink, and which bend angle to use. Electrical Pull and Junction Box Sizing Size a pull box for large conductors by NEC 314.28, for straight, angle, and U pulls. Electrical Parallel Conductor Sizing Size a large feeder as one conductor or parallel sets, with the NEC 1/0 rule and fill adjustment. Electrical EV Charger Circuit Sizing Size the wire and breaker for a Level 2 EV charger, and decide plug-in versus hardwired.