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Butt coupler / joint vs continious run for resistance loss

1836 Views 29 Replies 6 Participants Last post by  kennybobby
So, any super nerds out there that can help - I'm using Amphenol's G2 series 300 connectors for my 2/0 cable.

All these high-end connectors require multiple tooling and time to assemble - man tear ($$$) are at the feet of stupid mistakes like forgetting to mount a ring before you did this-or-that and now it can't be undone or reversed or blah blah blah (<cursing and being forced to order a new $100++ connector).

So, the question I have is, would a pig-tail design reduce the resistant of the overall run - point A Connector to point B connector vs point A Connector to butt joint to point B connector.

I can build a G2 connector in a controlled environment (my dinning room) attached to say a 24" length of 2/0 cable then make my run in the vehicle, join the butt to butt end to the pig-tail and Bob's you Uncle.

The question is, how much do I loose in resistance with a butt joint?

Obviously, I would use an industrial, hex crimped, tinned, copper connector then a double wall, adhesive heat shrink over it for both strength and water proofing.


- Patrick
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It looks like a good solution; probably couldn't measure any significant resistance increase unless the crimp wasn't done well.

What is the overall length of the 2/0 that would be used x (0.000080 Ohms per foot) --kinda hard to measure resistance that low.

In my book the Green One is the expert on crimping, Hammer Time ; couldn't find his dissection pictures but those are must see.
I can get those images for you.
I can get those images for you.
The images are at the end of the video. But here is a screen shot. Hammer vs hydraulic crimp. I will have to say that those thick connectors are difficult to hammer crimp because you can tear them. If you look closely at the part I crimped with the hammer you will see a small hole appeared and that would allow moisture and water if not properly sealed. So to avoid that you need to be sure to lubricate the tip of the crimper before crimping and be sure you don't tear them. They are thick but you can see the results. Some have commented on the hydraulic crimp as being a poor example but it was what someone else had done and used on their conversion that I fixed.
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Thanks for sharing that.

I can think of a handful of pros of hydraulic v hammer but the number one, all things being equal (horrible cliché), the control you need for aligning connector to cable you just can't come close with a blunt force blow.

My G2 connector have two separate crimp points per connector and require 1-2+/-cm accuracy of crimp to make the second crimp work AND that crimp has to be dead on for the proper sleeve / strength issues to be adhered to for the overall strength and connectivity of the connection.

Also, aren't you showing lead battery connections - is that a fair comparison to say and inline crimp or a tinned tight fit lug or ring?
Yes, I'd say a fair comparison. As each side of an inline splice connector is no different than the end of a lead acid connector for the battery. The style of inline splice is exactly like what I used so it is fair and if you are doing the crimping out of the vehicle you still have full control of position even with blunt force trauma to the connector. The hydraulic crimpers are not as easy as you may assume either. They are fiddly and unwieldy and the wire can come out if you let go before you have enough compression on your connector. A good solid blow will usually set the position and you will have a good solid connection. In the end it is your choice. Most think the blunt force is the lesser quality. I disagree. You can see the difference. If you need I can do another crimp with my hydraulic crimper with a splice like you have the cut it as well. I would sacrifice a connector for someone. Yes? No?
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Please do a show and tell with the hydraulic. Post a picture comparing them so people can see the small differences
I would say so people can see the difference and leave out the small. You did see a difference and a pretty substantial one in my image. Mine hammer crimp is also not a solid block of metal either. If you look you can see the wires but more tightly bound to help with vibration issues. With the crimped one when I removed them from the vehicle there were about 5 of them that just fell apart with no real tugging so the crimp was quite poor. Interesting that a hydraulic crimp is so crappy. Not to say all hydraulic crimps are crappy. Just showing a comparison between two different ways. I'll do a video and revisit this. I won't bother doing another hammer as you can already see what it does. I will however use my hydraulic crimper and cut it for you to compare. Give me a few days and I'll post when it's ready to view.
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