Wire Connection Methods For Vibration

[myrkr]

I'm working on creating a simple junction box for my solar panel setup on my van. I've got limited height under my panels, so the box is slim and just a little too short to use a din rail type midget fuse holder (2.3" tall fuseholders vs. 2.1" tall enclosure). So instead I started looking into a Littlefuse 3 fuse holder block and they will fit.

My question has to do with the wire connection type for these types of fuse blocks. I haven't used them before and am concerned with vibration since this will be van mounted and have ongoing vibration. I looked at Littefuses info and found the 3 options as follows, Screw with Pressure Plate, Screw, and Box Lug. I'm using 8AWG Ancor Marine wire and am wondering what wire connection type would be most resistant to coming loose from vibration? I originally envisioned using ring terminals on the wire ends and torquing the connection screw to spec, but maybe box lug is better? I assume using a threadlocker on the screw threads is a bad idea, so am wondering if anyone has any experience and can suggest what method would produce the most vibration resistant connection?

Oh and I should mention the junction box will be accessible if necessary, but I have to partially remove a solar panel to get to it so I won't be able to easily check the connections, so I'm looking for a solid connection I can trust. Here is the info I found in the Littlefuse tech documentation.

 

[mikefitz]

If its a single panel or two panels, you don't need a fuse, since the panel current can never exceed its Isc value. Fuses are only required where 3 or more panels or panel strings are connected in parallel.

Mike

 

[myrkr]

Thanks Mike, I should have mentioned it's 3 panels, so as you mentioned I have to run the fuses. Here are the panel specs, I have 3 of these on the roof of the van.

Panel Specs (Panasonic)
Max Power (Pmax) 325W
Short Circuit Current (Isc) 6.03A
Open Circuit Voltage (Voc) 69.6V
Maximum Power Current (Ipmax) 5.65A
Maximum Power Voltage (Vpmax) 57.6V
Max system Voltage 600V
Series Fuses 15A

 

[mikefitz]

should have mentioned it's 3 panels,

Could you run the cables into the vehicle and have the fuses there, or alternatively use MC4 inline fuse holders.

 

[myrkr]

Could you run the cables into the vehicle and have the fuses there, or alternatively use MC4 inline fuse holders.

I originally had planned around MC4 inline fuse holders, but after reading a bit more on them and learning that there was only truly one MC4 (Staubli) and then a rest of variants with potential for issues from corrosion to overheating I decided I'd rather stick with something more reliable like busbars. I've got two ideal spots to bring in the wires into the van, so I can bring the lines through after merging them, but don't have enough openings to bring through 6 lines. I had originally tried going down that path but it was going to require cutting into the van roof and I didn't want to do that. So I've got this junction box built and mounted under the panels. I'm thinking maybe using the box lug connector but using a longer stud so I can put a jamnut on the top to prevent it from backing out, then using ferrules on the wire ends terminating in the box lug.