ABB HCLD case studies
ABB HCLD · Put your knowledge to work in context.
The ABB High Voltage Certified Lineworker Distribution (HCLD) is a professional credential aimed at lineworkers who build, maintain, operate and restore high-voltage overhead and underground distribution systems. It is intended for journeyman-level practitioners and experienced technicians who already work on distribution plant and want independent verification of their competence across safety, construction, transformation, switching, testing and fault restoration. The assessment blends multiple-choice and written items with a practical or performance evaluation, so it tests hands-on judgment as much as recall. Content spans nine domains, with the heaviest emphasis on safety and regulatory compliance and overhead construction, followed by transformers and connections, then underground systems, switching and protection, testing and commissioning, troubleshooting, and tools and equipment. The ABB HCLD case studies are 5 cases and about 2,592 words.
1Energized Secondary Repair Under Time Pressure
A 25 kVA overhead transformer feeds a 120/240 V single-phase service to a small commercial customer. The customer reports partial power: half the building's circuits are dead while the other half work.
677 words, about 3 min2Recloser Lockout on a Branch with Suspected Conductor Slap
A 12.47 kV overhead feeder has a recloser at the substation and a sectionalizer midway down the main line. A lateral fused with a 25 K cutout feeds a rural branch.
666 words, about 3 min3Transformer Bank Reconnection for a Voltage Complaint
A customer on a 240/120 V single-phase service complains that motors run hot and lights are dim. The service is fed from a 50 kVA overhead transformer connected to a 12.47 kV primary.
447 words, about 2 min4Cable Fault on a Pad-Mounted URD Loop
A residential subdivision is served by a 15 kV underground loop with pad-mounted transformers and sectionalizing elbows. One transformer goes dark; neighbors on the same loop remain energized.
427 words, about 2 min5Discrepancy Between Field Test and Nameplate on a Rebuilt Transformer
A 75 kVA, 12.47 kV–480Y/277 V three-phase pad-mounted transformer is being commissioned after being rebuilt. Nameplate shows a 5.75% impedance and a 65°C rise.
375 words, about 2 min