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When a solenoid tester loses its skin

By Dennis Quinlan

April 2007

I am a commercial electrician with 11 years experience. Until about 2 years ago, I had always used a solenoid tester. One day I had to relocate a 480 V VFD for a cooling tower motor. I locked out the power, moved and rewired the equipment. Then I took the lock off, turned the disconnect on and proceeded to check the voltage at the VFD. I put my tester leads on A and B phase while I held the tester in one hand. Then the inside case of the tester slid out from the outside case, leaving the energized guts of the tester sitting in my hand. I was lucky I was wearing hot gloves. I removed the leads from the energized lugs, destroyed the tester with my linesmen's pliers (so no-one would find it and try to use it) and threw it in the trash. After work I went and bought a Fluke T3 tester. The Fluke is also more accurate than a solenoid tester, before I had trouble telling if the old tester was reading 208 V, or 240 V. That's important information when you're working on high leg delta systems.