clear picture of power cord defocused trained competent electrician setting holding red electricity tester

alternating background cable checking clear competent component conducting conductor construction contractor control cord current defocused electric electrical electrician electricity electronics engineer engineering equipment holding industrial industry information inspecting inspection installation instrument light maintenance man manufacturing monitoring occupation people picture power prior procedure professional protection protective red repairman resistance safety services setting structure tagging technician technology test tester testing trained training use voltage voltmeter wiring work worker workplace