CoolArc200 Wrong-Input Live Case

Case Setup

• Model: CoolArc200
• Incoming complaint: "It barely has output and sometimes seems confused about the plug."
• Arrival condition: adapter, dual-voltage cord set, and handwritten note from a helper are included
• Hidden trap: the trainee must separate wrong-input expectation and sense-path issues from a real output fault

Trainer Prompt

Use this intake statement:

"Customer says it worked fine at one shop, then felt gutless at a jobsite. They think the machine stopped recognizing 220."

Only reveal these if the trainee asks:

• the helper used an adapter they cannot identify confidently
• the complaint was worse on a temporary site receptacle
• the panel behavior was normal enough that no one wrote down an actual error

Allowed Document Flow

1. CoolArc200 fault workflow router
2. CoolArc200 measurement card
3. CoolArc200 board opening map only if the sense and input path still fails after external proof
4. CoolArc200 full guide

Trainer Injects

• If the trainee asks about the receptacle, tell them no one verified line quality under load.
• If the trainee asks about adapters, reveal that the adapter came from another machine kit.
• If the trainee wants internal access early, ask what proves the complaint is not still in the input path.

Pass Markers

• identifies this as an input-path and expectation case first
• proves supply, adapter, and input recognition behavior before discussing board replacement
• distinguishes low-output expectation from a true sense failure
• escalates internally only after the external input path is bounded

Automatic Fail Conditions

• assumes wrong input recognition without proving the supply path
• treats low output on doubtful branch power as automatic machine failure
• skips the adapter and plug path

Debrief Focus

• dual-voltage complaints are often stories about supply quality, not just stories about the machine
• the sense circuit matters, but only after the external path is actually controlled
• a good technician keeps the complaint in the cheapest provable zone first

Companion Docs

• WeldKing certification checkoff
• WeldKing training progression
• CoolArc200 guide