Cable connector question

[howardq99]

Hi everyone and happy fathers day to all who qualify!

I am finally upgrading my inverter to a Xantrex ProWATT 2000 that has 5/16" bolts for the DC inputs. On the battery bank I am using a Blue Sea Systems Dual MRBF terminal block with a 300A fuse that has 1/4" bolts.

To connect the inverter to my battery bank I am having some cables made by Genuinedealz, I'm going with 3ft of their 4/0 AWG marine wire. Using their custom configuration tool there is not an option for a "Heavy" walled tinned copper lug connector in the 1/4" size, the "heavy" connector is available in the larger 5/16", 3/8" & 1/2" sizes.

Would the standard 1/4" lug be acceptable?

I've got an existing 4 AWG cable with one of the "heavy" 5/16" lugs and it fits fine but I don't know how much larger one of the heavy 5/16"lugs for 4/0 cable would be and if it will fit.

Assuming it will fit, does anyone see anything wrong with using a "heavy" 5/16" lug instead of a standard 1/4" lug on the MRBF side of the cable connection? What about using the 3/8"heavy lugs on the 1/4" bolt (to be able to repurpose these cables in a future project as my hardware is upgraded)?

Thanks for your input!
Howard

[Almot]

wa8yxm wrote:
I would think a 5/16" lug on a 1/4" connector (4/16") would be dang near a perfect Fit. Do not forget some nice brass washers.

1/4" lug would be a better fit yet. But it looks like his are M8 studs, hence - 5/16.

Stainless washers will be fine too.

[howardq99]

Thanks for all the input, I appreciate the advice.

Are brass washers preferred over say Stainless Steel washers?

[wa8yxm]

I would think a 5/16" lug on a 1/4" connector (4/16") would be dang near a perfect Fit. Do not forget some nice brass washers.

[westend]

If you can, standardize cables and lug terminations so you have some emergency repair capability on board. In my TT, I have over 100' of 4AWG with 5/16" lugs, terminated in different lengths. If something gets ripped up, I could rearrange some cabling.

[Almot]

M8 indeed. A whole 1/256" smaller than 5/16" lug 🙂

[time2roll]

My link shows 5/16" stud. Although I think it is metric M8.

https://www.bluesea.com/products/2151/Dual_MRBF_Terminal_Fuse_Block_-_30_to_300A

[Almot]

On 1/4" terminal it seems only logical to use 1/4" lug. Yes, standard if they don't come in heavy wall option.
5/16" or 3/8" will be loose, thus negating the heavy wall advantages.