This has been brought up before. The old equipment had several advantages. One of them was that components were much larger and so were clearances. Mechanical build quality was also orders of magnitude better. Another advantage is that you would generally set them down while measuring, as opposed to a hand held DMM that you hold in your hand. So even if the AVO meter explodes, it's much less likely to injure you. It won't comply to the latest safety regs, but I'd rather trust my life to an AVO 8 which was the best they could make at that time than a cheap and nasty VC99 from whatever brand.
The Brymen 820 series do not appear to meet their rating either.
Pah. You kids with all your silly CAT3 600V/1000V etc multimeters. Back in the day we would use AVO 8 analogue multimeters, 20k ohm per volt. MASSIVE calibrated scale with mirror strip for parallax, absolutely no worries measuring mains or even three-phase. 2,500v AC/DC readings not a problem. Tested to 5kV. No silly fuses - a sprung cut-out button was all that was needed.
My current AVO is a 1970's "Test Set No.1" which was a military spec and measures 3,000v AC/DC (and all other ranges are in the 30's instead of 25's). It can even read 30uA.
Obscure Ever Ready cardboard box batteries only needed for the resistance ranges.
We also worked on TV's and Radios that were all totally live chassis - no isolation at all. The highly (in)efficient voltages were all generated using a massive wirewound "dropper" resistor with taps for all the HV, LV, and finally the valve heater circuits. It was an electric bar fire in the telly. Yes, the metal chassis was directly connected often enough to 240V Live. More modern sets like the Philips G8 chassis (with the fantastic Nixie tube channel indicator) actually used high tech SCR chopper mode power supplies instead of the bar-fire dropper. Of course, no isolation, it was all live. Quite scary.
Somehow I survived to tell this tale. You know what? I'm perfectly happy with my shitty cheap VC99. But for HV stuff I think I will just dust down that ancient Bakelite AVO 8 (Test Set No. 1).
ETA: A link for anyone interested in good old school stuff. http://www.richardsradios.co.uk/testsetno1.html
I have never seen a G8 with a Nixie tube!, would love to see one.
I have worked on loads of Live chassis TV's back in the day, you could get a belt off the aerial socket on some sets if leaning against an earthed VCR lol! And idiots that put external speakers or headphone sockets on them
DT830B - risk of electric shock due to insulation defects / risk of flashover, not compliant with EN61010 / LVD:
http://unsafeproducts.eu/2013/09/13/digital-multimeter-dt830b-digital-multimeter/
http://unsafeproducts.eu/2013/11/08/multimeter-%CF%88%CE%B7%CF%86%CE%B9%CE%B1%CE%BA%CE%BF-%CF%80%CE%BF%CE%BB%CF%85%CE%BC%CE%B5%CF%84%CF%81%CE%BF-digital-multimeter/
DT830B - risk of electric shock due to insulation defects / risk of flashover, not compliant with EN61010 / LVD:
http://unsafeproducts.eu/2013/09/13/digital-multimeter-dt830b-digital-multimeter/
http://unsafeproducts.eu/2013/11/08/multimeter-%CF%88%CE%B7%CF%86%CE%B9%CE%B1%CE%BA%CE%BF-%CF%80%CE%BF%CE%BB%CF%85%CE%BC%CE%B5%CF%84%CF%81%CE%BF-digital-multimeter/
I just bought a Uni-T UT203 clamp meter, and the input protection is... well, there isn't any. It's supposedly CAT2/3, but the only protection is a PTC. There's not even a fuse, so if something goes short while you're measuring mains voltage, you're going to have a very nice explosion. Blast protection is okay, there's rather deep walls, but I still wouldn't trust it. Additionally, there's no sort of isolation cutouts around the inputs, and a trace taps off the input and goes straight to the selector switch. I can see that arcing if you put a KV or two on it. (They also used a red wire to attach the common terminal? )
Unfortunately, I'm stuck with it; being an unemployed college student, it's all I could afford, at around $40 on Amazon.
DT830B - risk of electric shock due to insulation defects / risk of flashover, not compliant with EN61010 / LVD
Yup that's pretty bad. Not only is only fused for mA and uses the wrong fuse for the CAT rating, it looks horribly built. The other glaring issue is that whoever designed the circuit board just designed it as if it were a small signal board. No consideration for voltages creepage or clearance. On top of that, there appears to be no input protection at all. Keep this one for the car and low voltage electronics and keep it away from the wall socket!
Yup that's pretty bad. Not only is only fused for mA and uses the wrong fuse for the CAT rating, it looks horribly built. The other glaring issue is that whoever designed the circuit board just designed it as if it were a small signal board. No consideration for voltages creepage or clearance. On top of that, there appears to be no input protection at all. Keep this one for the car and low voltage electronics and keep it away from the wall socket!
This has to be one of the worst I have seen in a while! There is LITERALLY nothing between the 10A input and ground other than the CURRENT SHUNT!!!!!! That thing is BEYOND unsafe!
Yup that's pretty bad. Not only is only fused for mA and uses the wrong fuse for the CAT rating, it looks horribly built. The other glaring issue is that whoever designed the circuit board just designed it as if it were a small signal board. No consideration for voltages creepage or clearance. On top of that, there appears to be no input protection at all. Keep this one for the car and low voltage electronics and keep it away from the wall socket!
This has to be one of the worst I have seen in a while! There is LITERALLY nothing between the 10A input and ground other than the CURRENT SHUNT!!!!!! That thing is BEYOND unsafe!Gossen made a meter without a fuse on the A range (MetraHit 23S). It had a CAT II 1000V rating.
Electrical Safety (23S only)
Protection Class II per EN 61010-1:2001
/VDE 0411-1:2002
Measuring Category II
Operating Voltage 1000 V
Pollution Degree 2
Test Voltage 5.2 kV~ per EN 61010-1:2001
/VDE 0411-1:2002