TheHappyNomads
New Member
Decided to take a peek on eBay to see if I could find a deal on this final part to my PV setup -- and found a great one!
Class T 300a Fuse + Block
Class T 300a Fuse + Block
300a Class T Fuse and Block
- Thread starter TheHappyNomads
- Start date
timselectric
If I can do it, you can do it.
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Have you received it yet?
That seller is new, with no reviews yet. (Not necessarily a bad thing)
Your experience with them is valuable.
That seller is new, with no reviews yet. (Not necessarily a bad thing)
Your experience with them is valuable.
chrisski
Solar Boondocker
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- Aug 14, 2020
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Appears the picture the seller chose as the cover picture has rust on the stud. There’s some other things that make me think it’s not as good as blue sea like the fuse and lug attach to the same stud and looks like a larger lug may not fit.
Tulex
Solar Wizard
Don't like that I can't see the surface under the fuse. Looks like it's plastic, but can't tell.
timselectric
If I can do it, you can do it.
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That's weird.
The first time I clicked on it. It said zero reviews and stars.
Now, it's like your picture.
The 19 items sold, and 2 followers are the same as before.
Haze
New Member
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- Mar 6, 2021
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- 115
This appears to be a data sheet on them.
robbob2112
Doing more research, mosty harmless
Pure assumption here, looks like new old stock, possibly from car audio install shop that went bust. I get that from the description and datasheet. And the fact that the wires connect directly to the fuse studs.
The base and case both appear to be abs plastic. Not fantastic because it can burn but not until 230c typically.
The base and case both appear to be abs plastic. Not fantastic because it can burn but not until 230c typically.
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If it is getting that hot you've got issues already anyway!
TheHappyNomads
New Member
They are set to arrive today. I will keep everyone posted on condition
Tulex
Solar Wizard
Maybe, but still don't like it. We've seen post on here where plastic blocks have melted. I still like metal on metal, especially for a shared connector.
Wait maybe I'm missing something but how do you have metal on metal without a short circuit? It has to use plastic orbsome kind of insulator to mount to.
Tulex
Solar Wizard
Normal block, like blue sea, has 2 studs on each end, one for the fuse, one for the connector, both on the same bar. So, even if the plastic melts, both connectors are still solid.
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timselectric
If I can do it, you can do it.
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There's really not much difference between a single stud or two.
If the base melts, the conductive parts are free to move.
If the base melts, the conductive parts are free to move.
Tulex
Solar Wizard
From what I could tell, the studs are threaded into the busbar on the double studded ones I have. That means, you could actually remove the plastic and it would still work. If this single studded one is fuse on plastic, if you remove the plastic, you no longer have a tight connection.
Hedges
I See Electromagnetic Fields!
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- Mar 28, 2020
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His store sells surplus. Must have acquired some of these.
Another photo from his listing:
This is single stud design, so ring terminal is to be placed directly in contact with fuse terminal.
Unlike dual stud design, wire is free to come off and fly around when changing fuse.
If this design has plastic in the compressive path, that could relax and let contact overheat.
The instructions on max torque are in line, even high, for stainless hardware. That suggests plastic not in path.
e.g. 12.5 foot-lbs. for 5/16" hardware, a bit above this chart:
But check construction/assembly. If not already present, put a nut over the plastic and under the terminals being clamped, so only metal used for compression.
Another photo from his listing:
This is single stud design, so ring terminal is to be placed directly in contact with fuse terminal.
Unlike dual stud design, wire is free to come off and fly around when changing fuse.
If this design has plastic in the compressive path, that could relax and let contact overheat.
The instructions on max torque are in line, even high, for stainless hardware. That suggests plastic not in path.
e.g. 12.5 foot-lbs. for 5/16" hardware, a bit above this chart:
But check construction/assembly. If not already present, put a nut over the plastic and under the terminals being clamped, so only metal used for compression.
timselectric
If I can do it, you can do it.
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- Feb 5, 2022
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Maybe we will find out, when the OP receives theirs.
TheHappyNomads
New Member
Just opened everything up and here's a breakdown. Definitely NOS as they came in original unopened packaging. Not rust on the threaded rod. Looks like same anti-seize product I've used on spark plugs before. Fuse rests on the ABS with posts embedded into the mold it appear, they do not unscrew out and the bottom plate securing them has no movement and doesn't appear to be removable. Check out more detailed pics as well.
Hedges
I See Electromagnetic Fields!
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I see plastic in the compression path, and I don't like that.
Spin on a nut against the plastic, then stack cable and fuse in your preferred order or what fits (would be nice to have cable first). Then after both, add washers and nut.
Spin on a nut against the plastic, then stack cable and fuse in your preferred order or what fits (would be nice to have cable first). Then after both, add washers and nut.
