Craftsman Electricity case studies
Craftsman Electricity · Put your knowledge to work in context.
Craftsman Electricity is a trade-level credential for electricians and maintenance craftworkers who install, maintain, and troubleshoot electrical systems in industrial, commercial, and institutional settings. It sits between a general maintenance qualification and a full journeyman electrician license: candidates are expected to read drawings and the applicable electrical code, select and install wiring methods correctly, size branch circuits, feeders, and services, apply grounding and overcurrent protection rules, connect and control motors and HVAC equipment, work with transformers and distribution equipment, and diagnose faults safely. The Craftsman Electricity case studies are 5 cases and about 3,562 words.
1Rooftop Fan Motor Branch Circuit Trips on Start
A 25 hp, 460 V, three-phase rooftop supply fan motor has a nameplate full-load current of 34 A, service factor 1.15, code letter G, and a 40°C ambient rating. The existing branch circuit consists of 10 AWG THHN copper conductors in EMT, a 50 A inverse-time circuit breaker, and a combination starter with Class 10 overload heaters set at 38 A.
726 words, about 4 min2Detached Garage Feeder Grounding and Bonding Red Tag
A 200 A, 120/240 V single-phase service supplies a detached garage through a 100 A feeder. The feeder is 3 AWG copper THWN in PVC with an 8 AWG copper equipment grounding conductor, protected by a 100 A breaker at the house panel.
763 words, about 4 min3Dwelling Service Calculation With EV Charger and Tankless Proposal
A 2,400 ft² single-family dwelling is supplied by a 120/240 V, single-phase, 200 A service with 4/0 aluminum SE conductors. The existing loads are: electric range 12 kW, electric clothes dryer 5 kW, 4.5 kW water heater, a 4-ton air conditioner with a nameplate minimum circuit ampacity of 27.5 A at 240 V, and a 48 A Level 2 EV charger.
697 words, about 3 min4Transformer Neutral Overheating With Harmonic Loads
A 45 kVA dry-type transformer with a 480 V delta primary and a 208Y/120 V secondary supplies a 100 A panelboard. The secondary conductors are 2/0 copper THHN, and the panel main is a 100 A breaker.
668 words, about 3 min5Submersible Well Pump Voltage Drop and Thermal Trip
A 1.5 hp, 230 V single-phase submersible well pump is 350 ft from the house panel. The branch circuit is 10 AWG copper UF cable, protected by a 20 A two-pole breaker, with a pressure switch at the wellhead.
708 words, about 4 min