New fuse holder for clip-in battery

[soramimo]

hi all,

I have a blown fuse and melted [1] fuse holder on the battery of my Surface 604 Shred (2018). It's actually the second time this happened (the original fuse holder also melted as did the replacement fuse). Both times it happened with a fully charged battery when accelerating hard.

What is a good replacement fuse holder that can withstand high temperatures for this application? How to calculate the right amps for this fuse (I'm guessing it's something along the lines of 40A)? How can I try to avoid having the fuse holder melt on me (besides making sure all contacts are good)?

Thanks!

[1]

 

[E-HP]

Automotive blade fuses have a standard color coding, so green is 30A. Since the fuse isn’t blowing, but the holder is, I’d just skip the holder and solder directly to the blade fuse. There are several posts (frequent) on this issue, and it’s always due to cheap holders.

 

[soramimo]

Thanks for the quick response!

Two quick follow up questions. Do you think it would work to reuse the soldered on fuse sockets [1] (after some cleaning) to just stick in a fuse and tape off the contacts with electrical tape (so basically your suggestion w/o soldering).

Should I do want to go with a high-quality fuse socket, are there any brands you (or others who might see this thread) could recommend?

[1]

 

[E-HP]

Do you think it would work to reuse the soldered on fuse sockets [1] (after some cleaning) to just stick in a fuse and tape off the contacts with electrical tape (so basically your suggestion w/o soldering).

Nope.

Should I do want to go with a high-quality fuse socket, are there any brands you (or others who might see this thread) could recommend?

You could probably do a search and find a few options. The bottleneck causing the overheating are those contacts, which is why the fuse and holder are melted.

Please help diagnose a near meltdown

There's two parts to this issue, part one is a crash that damaged the hub motor cable, and part two is the discovery of a near melt down by the battery, which may have been caused by the crash, but might just be coincidence. Part 1: On my commute home a driver cut me off, which caused me to go...

endless-sphere.com

 

[Papa]

Should I do want to go with a high-quality fuse socket, are there any brands you (or others who might see this thread) could recommend?

Marine Grade Fuse Holder 8-GA, Fuses Included

Shop online DS18 HYDRO MFH8 Marine Water resistant Fuse Holder 8-GA. . FREE SHIPPING ON ALL US ORDERS.

ds18.com

 

[Diggs]

Hmmm... I don't think he has room for a marine fuse holder like that. These are the best (better?) blade fuse holders that I know of but they all have the inherent heating problem that they all suffer in high current applications. I've used them and crimped the leg clips tighter to help prevent issues.

 

[soramimo]

Thanks all for your help!

For now, I'll probably try to solder the fuse to the fuse socket of the old fuse holder (assuming the connection between the wire and the socket wasn't the problem), hopefully that'll do it for now.

Will report back here once done.

 

[scianiac]

For most builds I just use a MIDI/AMI fuse with well crimped ring terminals and bolts, then wrapped in some splicing tape. Whole setup is pretty small (you can also angle the terminals to fit in tight spaces), pretty cheap, makes good contact all around, and high current fuses are available.

 

[soramimo]

For most builds I just use a MIDI/AMI fuse with well crimped ring terminals and bolts, then wrapped in some splicing tape. Whole setup is pretty small (you can also angle the terminals to fit in tight spaces), pretty cheap, makes good contact all around, and high current fuses are available.

Great, I didn't know about these! Do you have any recommendations on which 1) crimping tools, 2) splicing tape and 3) ring terminal brands to go with (if you don't know what you're looking for, just searching on Amazon turns up a lot of garbage)?

 

[soramimo]

As an aside, do folks here have any concerns about using Wagos to splice in a fuse holder (e.g. the one recommended above) (for reference, I'm using Wagos around the house and love them!).

 

[scianiac]

I've seen some tests with wagos but I can't recall the results current wise. I use a hydraulic crimper but that's probably overkill unless you are using higher currents. Most of my crimps are random amazon and aliexpress, the ones that look like this with the flared ends and nice thick walls are best.

This tape is for some reason always on sale super cheap and works well. It's a self fusing tape like the silicone type but sticks to itself much better and is much stretchier so you can easily wrap it tightly around odd shaped objects (like a fuse with ring terminals) to waterproof them. So far it's best way I've found to seal up things like this in a way that seems reasonably durable and waterproof and can be easily removed. Doesn't seem to leave any residue like adhesive type tapes. Only downsides I guess would be it's not UV resistant (but many things aren't) and has a narrower temperature range than the silicone stuff but that's not needed for this use.

The holes in the fuses are 5.5mm so I use M5 bolts with washers and 1/4in ring terminals. You can also put something between the studs (I use some 3D printed strips but anything you can drill two holes in and isn't conductive would work) with an additional nut to reinforce the fuse for bending if it's somewhere where it will be exposed to bending.

 

[soramimo]

Thanks for all the great tips!

Because 1) the contact was bad just on one side of the old fuse holder 2) the crimped connector on the side of the battery was still ok and 3) that cable was too short to remove and reattach another crimp, I ended up doing the following (based on a mix-up of ideas from this thread).

- I ordered the fuse holder recommended by Diggs and cut it in half (so I could reuse the still intact side of the old fuse holder)
- I attached the wire of the fuse holder using a Wago (I know it says only 20A, but it should be ok up to 30A according to the IEC)
- Based on scianiac's idea of using a MIDI/AMI fuse, I bolted down the battery side of the old fuse holder onto the fuse, so hopefully that'll prevent any issues similar to the other side
- To minimize the chance of future connection problems, I applied some Dielectric grease on fuse and fuse holders
- Finally, I wrapped the hole thing in electrical tape and closed it back up (inspired by scianiac's idea of using self fusing tape)

Let's see how it goes, so far it's gracefully survived a trip with a few steep climbs! Thanks again for the help.