Although I'm using two cheapo Chinese meters inside a metal enclosure to measure heater current and voltage, there is no way I would use these for any serious measurement, particularly on a high energy circuit. The probes which came with them say "Cat III" which they most certainly aren't - they are CAT I with a following wind. The probe tips are far too long, and they have a double insulated symbol, but use single insulated wire.
Although this is a Fluke video, it is a good round up of what voltage categories are, what you have to look for, and even (if working at or near a mains incomer) what clothing to wear and the chilling consequences of not doing so after an arc flash. Plus some scary tests on cheapo meters, like connecting to volts on the ohms range, or volts when the plugs are in current sockets - flames and explosions.
https://www.youtube.com/watch?v=IzwN8yibjjA
All my DVM's (5) and probes are Fluke, and in fact have just bought a set of high energy CAT III/CAT IV probes from Farnell (£59 plus VAT) in the event that I have to work on our domestic distribution board - which I have done in the past. Best have them on hand.
Although this is a Fluke video, it is a good round up of what voltage categories are, what you have to look for, and even (if working at or near a mains incomer) what clothing to wear and the chilling consequences of not doing so after an arc flash. Plus some scary tests on cheapo meters, like connecting to volts on the ohms range, or volts when the plugs are in current sockets - flames and explosions.
https://www.youtube.com/watch?v=IzwN8yibjjA
All my DVM's (5) and probes are Fluke, and in fact have just bought a set of high energy CAT III/CAT IV probes from Farnell (£59 plus VAT) in the event that I have to work on our domestic distribution board - which I have done in the past. Best have them on hand.
