I wonder how many times a product has been certified, then the design changes but the company still uses the old cert.
On the cert it says:
"TÜV Rheinland performs checks to maintain the certification. Tests are carried out to ascertain whether the manufactured product still conforms to the tested type or whether changes have been made. Such inspections, which usually take place on an annual basis, also include a control of the quality system as well as the final examination. The aim is to determine whether mass production can ensure the safety requirements for the product."
The award of the GS mark is governed by the Product Safety Act and limited to a maximum of five years. It expires automatically if there is any change to the tested product.
From Fungus's review, I have know idea if the fuses were even certified or not.
I'm not sure how I could test that. The markings on them for the rated voltage were present and correct. Blowing them using 230V mains wouldn't give any real safety information.
Why wouldn't they be the correct fuses? The cert says there's a large organization grabbing meters directly off the production line and testing them.
As I mentioned, the safety fuses are independently certified just like the meter. As I understand it, you could use an fuse that has not been certified but how they would test it, I am not sure (that was the section I had included previously). I expect this is why the reputable brand meters always use certified fuses. Sorry, but I have damaged most of the junk fuses making demo videos so I don't have a lot of examples.
Fuse1, top to bottom is a SIBA, ASTM from Dave,
,
and a fuse marked SIBA.
Fuse 2 we can clearly see the first two have some sort of cert mark. The last fuse is the counterfeit SIBA. It's chewed up from pulling it apart when I made the videos but they were at least good enough not to have any cert markings on it. The 4th fuse has no markings beyond a voltage and current.
Fuse 3 is a close up of the 3rd fuse, actually a 1000V part made my Little Fuse.
In some cases, we can lookup the datasheets for the fuses to find out more about them. In the case of Dave's fuses, we now know that there are a few different data sheets floating around so make sure you get the correct one if you look it up.
I wonder how much checking really happens. Would an inspector even know what to look for? I am not so sure. Maybe they just buy them lunch and move on. It's also a bit strange that they would allow that Gossen to be approved when something as simple as the magnetic hanger can cause it to read low voltages in presence of high voltages. Consider that EMC report I had attached some time ago about the ESD testing. To me, these things just water down the usefulness of the standards. Go to TUVs website, it looks to me like a bunch of marketing people throwing a party.
In your video, I can't tell if they are a certified safety fuse or not. You could easily check it for any markings. Maybe see if you can find the datasheet for it.
I am limited in what I can do with my own testing. The highest energy transients I can produce are around 4-600 joules and I am not even close to a KA, let alone 10KA. Still even with these low levels, it's fairly easy to see why something sold for CAT III, this stuff becomes important.
https://youtu.be/xLDok9Sm07Q?list=PLZSS2ajxhiQAk2Q57Obdy-2yVNF-m_huu