Beware of Amazon's class t fuses

[Osmethne]

This is the crimper I use. https://www.amazon.com/Hydraulic-Ba...022-9bcd-ef830f0b379f&pd_rd_i=B06XR8BY65&th=1

It seems to work. My crimps survive a pull test. There is something not quite right about the crimper. It's hard to explain. I feel like I need 3 hands to use it.

 

[Bluedog225]

This is the crimper I use. https://www.amazon.com/Hydraulic-Ba...022-9bcd-ef830f0b379f&pd_rd_i=B06XR8BY65&th=1

It seems to work. My crimps survive a pull test. There is something not quite right about the crimper. It's hard to explain. I feel like I need 3 hands to use it.

It helps a lot to secure the crimper to your workbench or a big piece of wood. I use emt holders. I got much better results.

 

[featherlite]

@Hedges could tell us since he sees magnetic fields.

 

[JRH]

Best I could tell was that hey had yellow clips.

If you look inside the cover you will see a small compartment thst is not there on the standard ones .when closed it mates up to a seal that closes off that compartment from the outside air as to not allow sparks to create a fire…
Thats a short story version of the whole description blue seas main tech explained to me… they test em with propane to get their certification and such…

I have both types …but I don’t need protected ones , but I have some…

I believe all of the 5007 units , the yellow clamps ones , are protected…..( for up to 200;amp..)
I believe the 5502 units are available in both versions….( 225 to 400 amp)..

The model number ends with a -100 if it’s protected…( e.g 5007-100)…
No -100 if not….

 

[Hedges]

Without the AC I am not sure how the DC would couple across. @Hedges could tell us since he sees magnetic fields.

Either way it takes current flow in one wire to couple to the other wire.

Or voltage swing, even if no current beyond charging capacitance.

DC wouldn't couple electromagnetically, but could leak through resistance of bad insulation, wet splices, etc.

 

[MattiFin]

Bad choice - nylock will loosen over time

Best choice is a serated flange nut - it will stay in place and not loosen off.

I’m not totally sold on serrated nuts for current carrying connections. They tend to dig in and loose some of the clamping load even if they wont spin loose.

Bellewille washer aka disk spring is the industry standard solution for busbar joints and it maintains clamping load even after repeated heating cycles and/or creep. Just don’t use soft amazon crap bellewille washers. For US residents McMaster-Carr should be easy source of quality hardware.

 

[Crowz]

I plan on using these when I order more batteries in a week.

Lynx Class-T Power In - Victron Energy

The Lynx Class-T Power In connects and fuses up to two strings of Lithium batteries. It features a positive and negative busbar, and connections for two...

www.victronenergy.com

Its going to get a bit expensive but I like the design vs the fuse holders I have now.

 

[ThaiTaffy]

Back to post 1 it's quite worrying to think how many DIY batteries in wooden boxes have been made with these Amazon fuses connected the same way as OP with steel washers between current carrying contacts, there's lots of YouTube videos on DIY batteries that wouldn't necessarily go into the finer details of how to install a fuse correctly so a maker watching might just do the same as OP.

 

[D71]

Back to post 1 it's quite worrying to think how many DIY batteries in wooden boxes have been made with these Amazon fuses connected the same way as OP with steel washers between current carrying contacts, there's lots of YouTube videos on DIY batteries that wouldn't necessarily go into the finer details of how to install a fuse correctly so a maker watching might just do the same as OP.

So has this post title been determined as faulty of misapplication vs substandard products.?
Should the post title be changed to indicate use proper application in particular proper washer stack?

My guess: product as sold will work as designed if installed properly.

The advertising is interesting for many inaccuracies. By same token the advertising was correct it did not catch on fire and it maintained the fuse in the holder per the OP picture. My guess it will work as intended. “If applied properly.” Combination of misapplication with steel washers and poor cabling was OP. As a DIY we accept a lot of responsibility when taking on projects. The various inaccuracies as in this Chinese english description should of been a trigger.
The Fuse was added to this Fuse Holder and is sold under “wriboard” which is a chinese company on Amazon selling several different products there to include transfer switches.

The actual problem seems to be the misapplication by the seller as pictured and the OP not knowing any better. Ignorance.

There are special conductive spacers if they are needed that must be bought and steel washers should never be substituted. The fuse maker is part of the “wriboard” packaging from what have gathered. The Fuse maker has every safety test label of testing except UL. There were no false claims of UL. Why was the fuse and the holder faulted? Other then not UL brand

150VDC HSF21J High Speed Fuse

Westking is renowned as a 150VDC HSF21J High Speed Fuse professional manufacturer and supplier in China, specializing in providing high quality 150VDC HSF21J High Speed Fuse to meet your requirements. Additionally, we offer competitive pricing for customized 150VDC HSF21J High Speed Fuse. By...

www.westking-fuse.com

Again my guess it will work as intended for fuse and holder on Amazon. “If applied properly.” Combination of misapplication with steel washers along with poor cabling from OP. The OP was lucky.

I think the fuse holder is acquired by vender from another source “wriboard.”. I actually see nothing wrong with it for an actual application minus UL. Again if applied properly.

 

[Osmethne]

A fuse not being UL listed is not a trivial thing. If I buy a power tool that's not UL listed I'll know instantly if there's a problem. If I buy a fuse without any third party certification then I really have no idea. Could be just as good as a Littlefuse, could just be something that looks like a fuse.

As far as what exactly caused this meltdown here's some key pieces of information.

The system was running 80 amps across that fuse for hours on end for the last 6 months without issue.

Both sides of the fuse were fastened in the same way.

Neither of the crimps of the cable on either end of the fuse failed.

Neither side of the fuse came loose.

The overheating clearly originated on one side of the fuse.

If running that much current through steel was solely to blame It seems strange to me that this would happen suddenly and only on one side.

 

[robbob2112]

A fuse not being UL listed is not a trivial thing. If I buy a power tool that's not UL listed I'll know instantly if there's a problem. If I buy a fuse without any third party certification then I really have no idea. Could be just as good as a Littlefuse, could just be something that looks like a fuse.

As far as what exactly caused this meltdown here's some key pieces of information.

The system was running 80 amps across that fuse for hours on end for the last 6 months without issue.

Both sides of the fuse were fastened in the same way.

Neither of the crimps of the cable on either end of the fuse failed.

Neither side of the fuse came loose.

The overheating clearly originated on one side of the fuse.

If running that much current through steel was solely to blame It seems strange to me that this would happen suddenly and only on one side.

You are reaching here. You could have put the same fuse back in the melted holder but without the steel washer and it would have not gotten hot.

When I have a few minute I have a flir camera and a bunch of fuses I am going to run some tests while I blow a few. And when I do that test I'll put a steel washer in the mix

 

[cs1234]

You are reaching here. You could have put the same fuse back in the melted holder but without the steel washer and it would have not gotten hot.

When I have a few minute I have a flir camera and a bunch of fuses I am going to run some tests while I blow a few. And when I do that test I'll put a steel washer in the mix

Put steel washers on both sides, be sure to see if it gets hotter on the side that current flows through first.

 

[Osmethne]

You are reaching here. You could have put the same fuse back in the melted holder but without the steel washer and it would have not gotten hot.

When I have a few minute I have a flir camera and a bunch of fuses I am going to run some tests while I blow a few. And when I do that test I'll put a steel washer in the mix

If I make the same mistake on both sides of the fuse I'd think see the same consequences on both sides of the fuse.

Where am I going wrong here?

 

[seneysolar]

The overheating clearly originated on one side of the fuse.

If running that much current through steel was solely to blame It seems strange to me that this would happen suddenly and only on one side.

The cable end on that pre made automotive cable is steel right? If it is, that should answer your question.

 

[Bluedog225]

What an uphill slog this has turned into.

 

[Osmethne]

The cable end on that pre made automotive cable is steel right? If it is, that should answer your question.

Copper actually.

 

[seneysolar]

Copper actually.

Ok, just watch out for them.

This Deka brand says 100% copper conductor, but they are referring to the wire NOT the ends. I can pick it up with a magnet. These are BS and Deka should be ashamed to put their name on them.

 

[D71]

A fuse not being UL listed is not a trivial thing. If I buy a power tool that's not UL listed I'll know instantly if there's a problem. If I buy a fuse without any third party certification then I really have no idea. Could be just as good as a Littlefuse, could just be something that looks like a fuse.

As far as what exactly caused this meltdown here's some key pieces of information.

The system was running 80 amps across that fuse for hours on end for the last 6 months without issue.

Both sides of the fuse were fastened in the same way.

Neither of the crimps of the cable on either end of the fuse failed.

Neither side of the fuse came loose.

The overheating clearly originated on one side of the fuse.

If running that much current through steel was solely to blame It seems strange to me that this would happen suddenly and only on one side.

Steel is not a good conductor for carrying current It heats up. Resistance, heater. You have been told this more often then not on here in this very post. Go back and read them. The fuse never claimed UL listing on Amazon. The fuse is certified 7 ways from Sunday - today is Sunday with ISO and so on other testing for fuse ratings as I previous listed. Not UL. The fuse had no UL markings on it. Right? You bought and applied it without looking it up.

You took on the role of DIY and with that goes the responsibility of self education and research. Proper applications. You screwed up. Lucky you caused no serious damage. Pride is hurt. Wasted money. Get over it.

Why go cheap on safety of fuse ….. your battery rack was ~$3000+? No? You have to own it. The fuse was not listed as UL nor shown on it either. If that was your complaint. I think You bought based on cheap price point. We all do that. Me included. You made those decisions. Flat out …. The fuse - holder and cable product were mis-applied. They make conductive spacers - you could have made a conductor-spacer too. ‘You” mis-applied steel washers.

If I make the same mistake on both sides of the fuse I'd think see the same consequences on both sides of the fuse.

Where am I going wrong here?

Read ….. The fuse and the lug have to touch for a specific contact area depending on voltage and current.. The hardware used are there to CLAMP….TO HOLD THE FUSE AND LUG CONNECTOR TIGHTLY TOGETHER FOR THE ELECTRICAL BONDING OF THE 2 COMPONENTS The steel hardware are not there to pass current. You added resistance with improper Steel washer stack. Reads like Bad cable choice too.

You can probably see measured resistance if you buy a good meg ohm meter for a measurement. Get over it …. learn. No one is trying to harm you here. You were told repeatedly….bad washer stack = Resistance. Automotive Battery cable probably bad. You still do not want to accept it.

Get over the pride thing and read what ppl are telling you here. Ignorance is not a crime….. but it is no excuse when it comes to the law. Specific Metal types are selected and used for electrical connection applications for a reason. There are charts and such to select metals for current - electrical use. Silver copper gold and so on… steel is towards bottom. Zinc cadmium on bolt - fastener - clamping hardware offer a skin but still.. it is just a skin. Cadmium plate is high recommended with hardware for that reason. Stop rust too. You had the skin effect if they are indeed cadmium…plated steel then as current increases the cadmium skin can no longer support it. My best guess.

Again go back and read ALL THE OTHER REPLIES to your post. Common denominator…steel washer stack = resistance = heat…melted from heat = your result. Probable Bad cable selection. You have been told over and over the steel stack arrangement causes resistance which causes heat which produces your shown pictured problem in initial post. Throw in battery cable that might have steel lug which happens sometimes. Double whammy if that is the case. You claim copper lug on your cable.

Ignorance is only bad if you fail to educate yourself or to learn when the environment is there to gain knowledge which is being passed on. Steel is not a good conductor for passing current. The more you raise the current the sooner you will see it presented. That is a fact.

I have seen the same exact results done on diesel electric locomotive connections by young student electricians when those ppl mis-applied connections and improper hardware. They either learned from retraining and further education or they were FIRED. I am doing my best to communicate with you as have other ppl.

The multiple failure…is so far to communicate to you. They tried to help you.
Your obvious problem is washer Mis-application. You are responsible for that bad connection because you applied it and made a large heating element.

I have repeated myself over and over to you. Others in this post have tried to point it out too. 1 last time the lug - cable when properly selected should contact the fuse nothing should be between them that is not a good conductor rated to carry the current. . The lug should be fitted so as not to bind on the fuse.

 

[Osmethne]

Ok, just watch out for them.

This Deka brand says 100% copper conductor, but they are referring to the wire NOT the ends. I can pick it up with a magnet. These are BS and Deka should be ashamed to put their name on them.
View attachment 222540View attachment 222541

Interesting. I didn't know steel lugs were something some manufacturers did.

I only mentioned the ones I have are copper because these cables I have are worn enough that I can see the copper through the tin coating in places.

I've actually since replaced these with premade cables from Windy Nation since they seem to be a good source.

 

[rodrick]

I've actually since replaced these with premade cables from Windy Nation since they seem to be a good source

Windy nation, Temco and the local welding supply is the best cables for this type of application also proper hardware assembly and torquing the hardware is just as critical

 

[robbob2112]

If I make the same mistake on both sides of the fuse I'd think see the same consequences on both sides of the fuse.

Where am I going wrong here?

Well, IMO you very likely would have before it was over.

 

[SunDave]

Put steel washers on both sides, be sure to see if it gets hotter on the side that current flows through first.

If I make the same mistake on both sides of the fuse I'd think see the same consequences on both sides of the

Well, IMO you very likely would have before it was over.

This is a frame of reference miscommunication.

Both sides to one person means both sides of the fuse flange (on one "side" of the fuse)
and
Both sides to another mean, one on each flange of the fuse.

Just an FYI. I have no options in this situation. Hate to see a misunderstanding beyond the original misunderstandings here

 

[Osmethne]

This is a frame of reference miscommunication.

Both sides to one person means both sides of the fuse flange (on one "side" of the fuse)
and
Both sides to another mean, one on each flange of the fuse.

Just an FYI. I have no options in this situation. Hate to see a misunderstanding beyond the original misunderstandings here

I think part of the confusion is my fault for not communication how I'm accepting feedback.

I'm reading opinions in two different ways.

The first way, the most important way, is accepting critiques and suggested ways to improve. This might not be obvious but I have read everyone's opinion and acted on it.

Quality cables of the correct gauge. Check.
Correct torque. Check.
Noalox. Check.
No steel in the path of conduction. Check.
UL listed class T fuses. On their way.
If I've missed anything please let me know.

Maybe I haven't done a good enough job expressing gratitude to everyone contributing on their excellent input. So thanks everyone, great input.

The second way is just curiosity as to what exactly happened. And here I think is where the friction is coming from. Just because I'm unconvinced that a weakness in my methods caused this event doesn't mean I don't agree that it's a potential problem worth correcting.

So, everyone who is talking to me in all caps, I hear you, I see you. Your feedback is not lost on me.

And finally, who wants to see the inside of a class t fuse?



Here it is with the case cut open. That ceramic layer was a bitch.

Here it is with the sand blown out.




An interesting design. 4 fuse elements with strain relief encased in sand inside a ceramic chamber protected by... brass? aluminum?

 

[ThaiTaffy]

I think part of the confusion is my fault for not communication how I'm accepting feedback.

I'm reading opinions in two different ways.

The first way, the most important way, is accepting critiques and suggested ways to improve. This might not be obvious but I have read everyone's opinion and acted on it.

Quality cables of the correct gauge. Check.
Correct torque. Check.
Noalox. Check.
No steel in the path of conduction. Check.
UL listed class T fuses. On their way.
If I've missed anything please let me know.

Maybe I haven't done a good enough job expressing gratitude to everyone contributing on their excellent input. So thanks everyone, great input.

The second way is just curiosity as to what exactly happened. And here I think is where the friction is coming from. Just because I'm unconvinced that a weakness in my methods caused this event doesn't mean I don't agree that it's a potential problem worth correcting.

So, everyone who is talking to me in all caps, I hear you, I see you. Your feedback is not lost on me.

And finally, who wants to see the inside of a class t fuse?

View attachment 222581

Here it is with the case cut open. That ceramic layer was a bitch.

Here it is with the sand blown out.

View attachment 222582


An interesting design. 4 fuse elements with strain relief encased in sand inside a ceramic chamber protected by... brass? aluminum?

So from the teardown we can say the fuse is of reasonable quality many of the really cheap Chinese ones don't even have a silica filler, looks to be brass unsure of copper/tin ratio but the ceramic jacket looks to be thick and the fuse links seem to angled in a way that would stop welding after the fuse is blown. All in all I would likely happily use, even without the UL certificate fitted correctly of course.

Thanks for the teardown.

 

[B-ManFX4]

Ok, just watch out for them.

This Deka brand says 100% copper conductor, but they are referring to the wire NOT the ends. I can pick it up with a magnet. These are BS and Deka should be ashamed to put their name on them.

I'm not trying to be a jerk here but that cable is marked for its intended use - as a STARTER cable. The steel lugs are perfectly fine for that application. Starter cables with steel lugs are used by many automotive manufacturers. Steel lugs are helpful for fatigue resistance because of the vibration / constant movement between a rubber-mounted engine and a body mounted relay or solenoid.

The issue here is using a cable for something other than its intended purpose - not that the cable is junk. Deka has no reason to be ashamed.