I was trying to do a power calibration on a Tasmota smart switch, using this procedure:
I had an 25W incandescent globe (resistive load), wired up in a bayonet holder:
I have a digital multimeter (Fluke 287), set to A (current), with the probes plugged into COM and A:
I turned on the smart switch, and then tried to measure the current by touching the two terminals on the bottom. (The smart switch was showing roughly 0.1 A flowing through)
There was a flash, and a bang from the probes. I also noticed part of the red probe tip appears to have melted.
It's been a while since my elec education, so I'm assuming I did something silly her. Can somebody explained what happened here?
Is it likely there was damage to the DMM?
What is the correct way of measuring the current here?