I've been taught there should be enough force in the crimping tool to cold weld the crimp and the cable together for a proper crimp connection.
- Thread starter Brad93
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I've been taught there should be enough force in the crimping tool to cold weld the crimp and the cable together for a proper crimp connection.
Agroshield
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If oxidation is a problem, is there any sort of paste you can slather over the joint before applying the heatshrink to stop the atmosphere getting to the cable?
A search for 'oxide inhibiting joint compound' seems to show what you need. If you know any company that does building lightning protection, they will have some.
E.g.
https://www.cablejoints.co.uk/sub-product-details/resin-cable-joints/penetrox-compound-paste
https://www.ebay.co.uk/itm/184203588903
It is possible to buy tinned copper cable for use in harsh environments. I do not know if this is available in such large CSAs or if it would be economic.
Is there any kind of flexing between cable lug and cable when in use? That might be exacerbating the problem. Some kind of strain relief clamp to hold the connection rigid, such that the first bit of bending occurs well down the insulated section of cable might assist.
A search for 'oxide inhibiting joint compound' seems to show what you need. If you know any company that does building lightning protection, they will have some.
E.g.
https://www.cablejoints.co.uk/sub-product-details/resin-cable-joints/penetrox-compound-paste
https://www.ebay.co.uk/itm/184203588903
It is possible to buy tinned copper cable for use in harsh environments. I do not know if this is available in such large CSAs or if it would be economic.
Is there any kind of flexing between cable lug and cable when in use? That might be exacerbating the problem. Some kind of strain relief clamp to hold the connection rigid, such that the first bit of bending occurs well down the insulated section of cable might assist.
Hood
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That is what is used in marine applications in fact it has to be used on any new builds.
J1nx
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Solder a crimp would not be a good idea but feel free to try it 
I use a cembre battery crimper (runs Metabo batteries), it’s great, too pricey unless earning though.
My crimps have been dissected and pull tested and then kept for future reference. A proper crimp will not corrode inside, cut open a tri-rated cable that has been properly done.
I use a cembre battery crimper (runs Metabo batteries), it’s great, too pricey unless earning though.
My crimps have been dissected and pull tested and then kept for future reference. A proper crimp will not corrode inside, cut open a tri-rated cable that has been properly done.
Brad93
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Has to be a ring terminal really due to the fact that the machines have studs for ring terminals and the 2000A rotary ground has The same.
It’s not like it’s burning up a cable a job but it would be good to just get the best connection possible.
It’s not like it’s burning up a cable a job but it would be good to just get the best connection possible.
finyuk2005
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would be interesting to see how hot the crimps are getting, wouldnt that be why the cable is "corroding" so fast?
hotponyshoes
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What about making up a short length from the expensive tinned cable then put a dinse on the end of that to connect to a longer length of cheaper cable.
Or strain relive the end of it. A foot of silicone hose the correct ID, slit down the length of it.
Stick it over the lug and cable, one cable tie holding it tightly around the lug, a couple more holding it to the cable.
Or change the way it mounts, run the cable in a loop and fix the loop in place so there is no strain on the lug.
When I make leads up I grip the copper, pull the insulation back a bit, trim the length of the lug socket from the end of the copper, crimp, then work the insulation back over the body of the lug.
I have got some strain-relief heat shrink that's pretty tough. Let me know the o/d of the cable and I can send you a bit to try if you like
Or strain relive the end of it. A foot of silicone hose the correct ID, slit down the length of it.
Stick it over the lug and cable, one cable tie holding it tightly around the lug, a couple more holding it to the cable.
Or change the way it mounts, run the cable in a loop and fix the loop in place so there is no strain on the lug.
When I make leads up I grip the copper, pull the insulation back a bit, trim the length of the lug socket from the end of the copper, crimp, then work the insulation back over the body of the lug.
I have got some strain-relief heat shrink that's pretty tough. Let me know the o/d of the cable and I can send you a bit to try if you like
I bought a 16 Tonne hydraulic Chinese one a few years ago for $70 delivered from E-Bay, mine does 10mm to 300mm, so far it has work flawlessly, then again I don't do many cables and the largest I have made has been 90mm, but so far so good and it came with a big range of dies.
hotponyshoes
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Another option for the amount of use you are giving it might be a spider connection,
Run the 95mm to a fixed point near the machine, connect it to an insulated stud or a row of dinse sockets on a bus bar.
Then run 3 or 4 smaller flexible cables out to the moving parts.
Smaller might be more flexible and stand up to it better.
Stone shakers in quarries use that type of setup.
Run the 95mm to a fixed point near the machine, connect it to an insulated stud or a row of dinse sockets on a bus bar.
Then run 3 or 4 smaller flexible cables out to the moving parts.
Smaller might be more flexible and stand up to it better.
Stone shakers in quarries use that type of setup.
if they're failing that regularly & quickly there's definitely something strange, high current and long running times shouldn't cause oxidisation nor failure of a correctly done crimp over such a short time. As a comparison, LV and HV electrical switchboards can carry sometimes thousands of amps either on busbars, transformers then often hundreds on crimped lug connectors to switchgear or field terminals, and they run all day long for moths between maintenance intervals without issue. Albeit in dry cabinets and little risk of condensation.
Hood
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Further to my post the last day I decided to give the chopped crimp a quick polish to see if it showed any imperfections.
Looked good so gave it an etch to see what would show and as you can see the copper crimp is quite clearly visible and actually looks like in some places it has deformed to fill voids at the edge of the cable.
Looked good so gave it an etch to see what would show and as you can see the copper crimp is quite clearly visible and actually looks like in some places it has deformed to fill voids at the edge of the cable.
