Chint High AIC fuses - Temp verse resistance testing class T, MRBF, ANL, Mega, and CB

[robbob2112]

These fuses were mentioned in the house burned down thread over in up-in-smoke. I purchased two models and fuses off aliexpress to see how the resistance changed over time when running current through them. The thread below is the beginning of that discussion.

House burned down

do we know OP's pack rough current drawn at that fateful wee hour ? and was there not a smoke alarm ? or the Nest supposedly served that purpose ? Apparently there is a "steam" setting on the Nests to avoid false triggers from showers etc, and therefore they didn't trigger on the smouldering fire.

diysolarforum.com

The reason they are interesting is because they have a much higher DC rating for AIC (amp interupt current) than the class T


These fuses are similar in appearance to the NT00, NT1, and NT2 fuses availble in the UK and Europe. They actually look pretty much identical except for the markings.

https://www.parkelect.com/en/ETEK/b-186.aspx?CategoryIDs=405&Page=1

https://www.farnell.com/datasheets/41144.pdf - page 22

The NT2 is CE listed

Neither of these fuse types are UL listed so use at your own risk.


I have te two Chint fuses, several ANL fuses, some class T fuses, a Mega fuse, and a common lever breaker of a good brand.

I will run a hundred or so amps through them and measure temperature and resistance at a set interval. We know resistance increases with temperature so I was curious by how much.

The smaller of the Chint fuses I intend to blow on purpose then take it apart to examine build quality and see what is inside.

Attached are the documents I can find concerning them.

Markings on the fuses -
CCC - China Compulsory Certification - Chinese company that does standards like UL listing in the US

What is CCC - MPR China Certification

This is a comprehensive overview of the China Compulsory Certificate, or CCC in short. Many products need CCC to be exported to China.

www.china-certification.com

reinspection annually

TUV - Technischer Uberwachungs-Verien - - German Company that does standards similar to UL listing in the US

Not found

www.techuberver.com

https://nationalfuse.com/wp-content/uploads/2022/04/common-fuse-markings.pdf

 

[Dynoman]

I have te two Chint fuses, several ANL fuses, some class T fuses, a Mega fuse, and a common lever breaker of a good brand.

I will run a hundred or so amps through them and measure temperature and resistance at a set interval. We know resistance increases with temperature so I was curious by how much.

It will be interesting to find out the results. Once used a 110amp Littlefuse slow blow class T at 90 amps with it getting hot to the touch. Replaced with 150amp Littlefuse fast blow class T and at 90 amps it was barely warm.