Two separate incidents:
-testing lines when replacing light fixture. Hot (120VAC) and N are insulated separately but connected together. Black lead to GND screw (which turns out wasn't actually grounded) and Red lead to Hot.. I'm guessing it's just arcing from touching a live wire with no return.
-testing an output on a PLC where everything has been running fine. Red lead to output, Black lead to 24VDC and then to DCCOM just to see both.. I saw sparks and just stopped testing it.
I'm more concerned about what happened the second time.. but it concerns me when I see sparks when my meter is set to V, and leads are in the proper V and COM ports.
-testing lines when replacing light fixture. Hot (120VAC) and N are insulated separately but connected together. Black lead to GND screw (which turns out wasn't actually grounded) and Red lead to Hot.. I'm guessing it's just arcing from touching a live wire with no return.
-testing an output on a PLC where everything has been running fine. Red lead to output, Black lead to 24VDC and then to DCCOM just to see both.. I saw sparks and just stopped testing it.
I'm more concerned about what happened the second time.. but it concerns me when I see sparks when my meter is set to V, and leads are in the proper V and COM ports.