Calling all Copper Lug Guru's - which lug would you choose and why?

[TerryTtibbs]

Calling all Copper Lug Guru's - which lug would you choose and why?

I have ordered from 2 suppliers. 1 is an electrical supplier and the other specialise in DC cable and Forklifts, HGV and all the big Automotive stuff.

The shorter lugs on the left are from the DC cable and big stuff guys and are the more expensive by 20%, they also have a smaller inspection window, both weigh 8g.




Opinions please.

 

[timselectric]

Either, will do the job. As long as you get a proper crimping.

 

[740GLE]

I’d go with the longer barrel, might be able to get two crimps on it.

What are you using to crimp?

 

[TerryTtibbs]

Either, will do the job. As long as you get a proper crimpin

I’d go with the longer barrel, might be able to get two crimps on it.

What are you using to crimp?

Burndy Dieless indent MY29-11 https://prnt.sc/9AL2wzeKCVPa

 

[RCinFLA]

The thickness of lug metal is very important. Cheap lugs are formed from thin copper.

Think about the hollow tube from where the inserted wire ends inside the tube to where the lug flattens out for the terminal surface connection. The quarter to half inch or so of hollow tube is pure extra series resistance that adds resistance dependent on how thick the lug's copper shell is.

Nickel-tin or nickel-plated copper lugs is best. Nickel is used for inter-metallic migration barrier. Tin is solderable, nickel is not very good to solder to. You do not want dissimilar metal galvanic interaction which is why it is good to have a nickel-plated barrier. It can be buried under the surface tin plating, so you get the nickel barrier on top of copper and good tin plating soldering on surface.

Should not use bare copper lug especially when connecting to aluminum battery terminals. It will eat away and pit the aluminum over time. Bare copper lugs are okay when connecting to brass terminal posts like on a current shunt. Just clean oxide away before assembling. Keep your dirty, salty fingers off the cleaned contact surfaces.

The threaded bolt is for compression, not for passing current. The connection resistance is surface to surface flat area and uniform compression pressure across the surfaces. Use a lug with the proper sized hole. Larger hole just reduces surface to surface contact area. A strong stainless flat washer on top of lug under bolt head can help apply uniform pressure across the flat contact to contact surfaces.

High current connections require a great amount of attention to detail. One of the common mistakes made by DIY'ers battery interconnects.

Do not scrimp and cut costs by using cheap thin wall lugs. If a lug ad listing does not specify gauge of lug metal do not buy them.

 

[WYtreasure]

The thickness of lug metal is very important. Cheap lugs are formed from thin copper.

Think about the hollow tube from where the inserted wire ends inside the tube to where the lug flattens out for the terminal surface connection. The quarter to half inch or so of hollow tube is pure extra series resistance that adds resistance dependent on how thick the lug's copper shell is.

Nickel-tin or nickel-plated copper lugs is best. Nickel is used for inter-metallic migration barrier. Tin is solderable, nickel is not very good to solder to. You do not want dissimilar metal galvanic interaction which is why it is good to have a nickel-plated barrier. It can be buried under the surface tin plating, so you get the nickel barrier on top of copper and good tin plating soldering on surface.

Should not use bare copper lug especially when connecting to aluminum battery terminals. It will eat away and pit the aluminum over time. Bare copper lugs are okay when connecting to brass terminal posts like on a current shunt. Just clean oxide away before assembling. Keep your dirty, salty fingers off the cleaned contact surfaces.

The threaded bolt is for compression, not for passing current. The connection resistance is surface to surface flat area and uniform compression pressure across the surfaces. Use a lug with the proper sized hole. Larger hole just reduces surface to surface contact area. A strong stainless flat washer on top of lug under bolt head can help apply uniform pressure across the flat contact to contact surfaces.

High current connections require a great amount of attention to detail. One of the common mistakes made by DIY'ers battery interconnects.

Do not scrimp and cut costs by using cheap thin wall lugs. If a lug ad listing does not specify gauge of lug metal do not buy them.

Learning sumpin every day, thanks

@TerryTtibbs
What am I looking at here?

 

[TerryTtibbs]

Just used my new Burndy crimpers and although they are stupid money you can tell the difference. It is night and day between the chineesiums and the proper calibrated ones.

These are 4kg and 600m long, not the sort of things you carry around in your pocket, but they are effortless. The machining of the body is perfect, really no comparison at all, not even close. Worth every penny of the $842.

Results below.

 

[TerryTtibbs]

The thickness of lug metal is very important. Cheap lugs are formed from thin copper.

Think about the hollow tube from where the inserted wire ends inside the tube to where the lug flattens out for the terminal surface connection. The quarter to half inch or so of hollow tube is pure extra series resistance that adds resistance dependent on how thick the lug's copper shell is.

Nickel-tin or nickel-plated copper lugs is best. Nickel is used for inter-metallic migration barrier. Tin is solderable, nickel is not very good to solder to. You do not want dissimilar metal galvanic interaction which is why it is good to have a nickel-plated barrier. It can be buried under the surface tin plating, so you get the nickel barrier on top of copper and good tin plating soldering on surface.

Should not use bare copper lug especially when connecting to aluminum battery terminals. It will eat away and pit the aluminum over time. Bare copper lugs are okay when connecting to brass terminal posts like on a current shunt. Just clean oxide away before assembling. Keep your dirty, salty fingers off the cleaned contact surfaces.

The threaded bolt is for compression, not for passing current. The connection resistance is surface to surface flat area and uniform compression pressure across the surfaces. Use a lug with the proper sized hole. Larger hole just reduces surface to surface contact area. A strong stainless flat washer on top of lug under bolt head can help apply uniform pressure across the flat contact to contact surfaces.

High current connections require a great amount of attention to detail. One of the common mistakes made by DIY'ers battery interconnects.

Do not scrimp and cut costs by using cheap thin wall lugs. If a lug ad listing does not specify gauge of lug metal do not buy them.

Thanks for the detailed reply. I have gone with the more expensive lugs which are from an iso9001 registered company and the lugs confirm to various BS (british standard codes). Just by gripping and moving the lug around on the crimp performed with the Burndys the connection feels absolutley solid and feels like it's part of the crimp. Hard to explain untill you feel it for yourself and compare it to the chineesium hex crimpers results. So in summary it pays to buy the correct cimpers and atleast I have peace of mind that I won't get hot spots in my high current draw circuits. From my results it IS WORTH the extra investment, or even worth renting them for the day from a lease rental tool company. I spent a few hours reading about crimp types and I even called the company who specialises in crimping and big current DC stuff and they said they still use indent crimps on most stuff. The old boy said it may not be as pretty as a HEX but every load test they have done the indent crimp comes out on top. Indent also allows for more tolerance in the lug sizings and the variation in copper cable tolerances.

 

[TerryTtibbs]

Elcheapo Hydraulic Hex crimper results, as expected...stick to Burndy mechanical indent crimps eh! Giggles

Elcheapo Hydraulic Hex crimper results, as expected...stick to Burndy mechanical indent crimps eh! https://prnt.sc/exkhLIeFxxnm $50 Amazon hydraulic crimpers. Metric 35mm copper lug Be stamped. 35mm copper 1500VDC cable. Cut carefully with a dremel grinding wheel. Was a bit eager in the...

diysolarforum.com

My results posted above from cheap hydraulic hex crimping tool vs Burndy Mechanical My29-11.
Lot's of documentation floating around on the net for those who are interested. The whole crimping game is vast, I didn't realise how indepth you can go.

"The complete compression of wire strands using a hexagonal crimp and standard crimping dies is not possible. This means standard hexagonal crimps are not gas-tight (see gas-tight oval crimps at the end of this article)."

Hexagonal v Indent Methods of Crimping - Cable Lugs, Crimps & Tools

THORNE & DERRICK are UK and international specialist distributors of LV, MV & HV Cable Installation, Jointing, Substation & Electrical Equipment – we service UK and global businesses involved in cable installations, cable jointing, substation, overhead line and electrical construction at LV...

www.powerandcables.com

https://media.province-electric.com/panduit/2021q3/documents/7bf5ba299d2ad73bae6683d24ff7d30255953eea.pdf

 

[WYtreasure]

Elcheapo Hydraulic Hex crimper results, as expected...stick to Burndy mechanical indent crimps eh! Giggles

Elcheapo Hydraulic Hex crimper results, as expected...stick to Burndy mechanical indent crimps eh! https://prnt.sc/exkhLIeFxxnm $50 Amazon hydraulic crimpers. Metric 35mm copper lug Be stamped. 35mm copper 1500VDC cable. Cut carefully with a dremel grinding wheel. Was a bit eager in the...

diysolarforum.com

My results posted above from cheap hydraulic hex crimping tool vs Burndy Mechanical My29-11.
Lot's of documentation floating around on the net for those who are interested. The whole crimping game is vast, I didn't realise how indepth you can go.

"The complete compression of wire strands using a hexagonal crimp and standard crimping dies is not possible. This means standard hexagonal crimps are not gas-tight (see gas-tight oval crimps at the end of this article)."

Hexagonal v Indent Methods of Crimping - Cable Lugs, Crimps & Tools

THORNE & DERRICK are UK and international specialist distributors of LV, MV & HV Cable Installation, Jointing, Substation & Electrical Equipment – we service UK and global businesses involved in cable installations, cable jointing, substation, overhead line and electrical construction at LV...

www.powerandcables.com

https://media.province-electric.com/panduit/2021q3/documents/7bf5ba299d2ad73bae6683d24ff7d30255953eea.pdf

On which side of the pond are you located? US or EU

The link in my signature on battery melt down is worth reading. Great info on crimping & such.

 

[TerryTtibbs]

On which side of the pond are you located? US or EU

The link in my signature on battery melt down is worth reading. Great info on crimping & such.

UK, funny actually as we used to have a lot of AWG up until about 15 years ago and then it all filtered out into Metric. I tried crimping AWG2 on 35mm lugs with the HEX crimper and it looked fine until I hung my dog from it and it came off.

On a serious note yes the correct lugs make a difference and I am sure the HEX cheapy crimpers will do their job but I have 24KW of batteries so I want to make sure I have decent crimps.

25 years ago we didn't care and used to bash it with a hammer and then solder it over the gas stove, lol. Times have changed now though.

 

[HRTKD]

My preference would be the lug on the right. I want as much surface contact from the lug as possible.

This may not be a marine install, but many of us in the RV community look to the ABYC regulations for guidance. I thought that I recalled reading that ABYC standards do not allow for cable lugs with holes in them (holes other than the hole that the cable is inserted into, of course).

 

[Zil]

Can you find FTZ or ANCHOR brand lugs.

 

[TerryTtibbs]

Can you find FTZ or ANCHOR brand lugs.

The FTZ look really nice, but is $80 for 25 lugs and then $135 shipping to Europe.

 

[onokai]

I like to coat the strands with Copr-shield and slip on a heat shrink tube over wire beore crimping and after crimping slide it over and heat
The Copr-shield is spendy but works great ands the tubing keeps it localized as it messy conduive stuff.

CP8-TB Thomas & Betts Kopr-Shield Compound, 8-Oz

Thomas and Betts offers the CP8-TB Kopr-Shield compound. This cable preparation compound is the copper colloidal surface treatment that protects, lubricates and enhances conductivity between all electrical connections. Packaged in an eight ounce container with a brush, it meets the requirements...

www.specialized.net

 

[Zil]

Ah. What I like is they are heavy copper with tin plating. I would think you can find equivalent lugs in Marine Grade Supply Houses or Ship Chandlers in EU.

 

[Danke]

Where are guys buying compression lugs? I have only found expensive retailers in my search so far. Need them for 4/0 Welding K cable.

 

[Nobodybusiness]

Calling all Copper Lug Guru's - which lug would you choose and why?

I have ordered from 2 suppliers. 1 is an electrical supplier and the other specialise in DC cable and Forklifts, HGV and all the big Automotive stuff.

The shorter lugs on the left are from the DC cable and big stuff guys and are the more expensive by 20%, they also have a smaller inspection window, both weigh 8g.


View attachment 92092View attachment 92093View attachment 92094View attachment 92098

Opinions please.

Personally I don’t like the ones with inspection windows.

I have had them corrode from that point in before.

Either of those will work though.