I was taught to do cable lacing to make bespoke harnesses for all manner of equipment as well as for some vehicles before using adhesive tape to outer wrap them .
- Thread starter Dapph2
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When I was doing an apprenticeship with the (new then from GPO) British Telecom around 1980-82, they taught you to do copper & aluminium cable jointing, on grease-filled cables & taped multiple colour-coded arranged wire pairs.
Just how you spaced and laced the layers, from centre working outwards, how many wire twists, staggering the joints to allow crimps to lay flat & minimise overall joint size, specific grease-filled Crimps.... the whole exercise was planned and specified to the nth-degree.
(Encasement in Joints with 2-pack Epoxy, and just coming in then were injection moulding Joint encasement as well.... while the very first TXE exchanges and fibre-optic cables were just coming in. How things have changed in 45-years!)
Ubique
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My experience is mostly automotive and prime power generation up to 500kW gensets - so lots of 240mm2 SWA crimped lugs!
TBH, there could be anything in automotive control units, we rarely crack them open as there's little point other than confirming water ingress.
I have done (once - as its a damned silly idea with the weight, specified by a "colleague" who might have got the current maths & cable requirement right, but had no practical clue about moving & using the stuff) made up crimped 300mm2 cables.
As you say, 240mm2 was generally the max, and the bigger sets just used multiple cable runs on each leg of up to 240mm2, with lengths usually limited to 25M (& daisy chain if the run was longer).
240mm2 is plenty heavy enough to handle when you've a big set (or synched pair) and 15 of them to run out and hook up. I did plenty of load bank testing, & humping cable around makes it quite physical!
sako243
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The main reason it is preferred is speed and skilled labour is not required as you've stated but it relies on proper equipment to do it as per manufacturer's specification.
The only thing that matters is strain relief, it doesn't matter whether the joint is soldered or crimped, all will fail if the harness and connector don't have proper strain relief and attachment.
I dealt a lot with high end electronics equipment for use on military and aerospace applications and we'd use both but the assembly was done by qualified technicians who damn well knew how to solder. These saw far more vibration and forces than a typical vehicle and didn't have any failures. We did have a structural failure on something on a boat due to sustained G forces. The response when asked what G force they'd hit (because system had been over engineered already) was 'we don't know, they came under fire, they "weren't" meant to be there, they just got the hell out'.
TryingToWeld
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NEVER solder a high current connection ! If the joint gets hot and the solder melts it can come apart.
ALWAYS crimp it !
ALWAYS crimp it !
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Have to disagree, welder connections carrying a few hundred amps were soldered from the factory on our Honda robots, I've resoldered a few when replacing cables with no issues.
MetalMonkey
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It is worth noting, anderson connections typically aren't fitted with any strain relief.
Although the connector itself can be bolted down.
Reading all the thread again I guess withsuch vexation vicious litigation we now get ,you need to get the makers manual for advice on what they say & do it. If no manual is available offer your approved training and if there is none of that rent a council house and work van or you'll likely be taken to the cleaners if a claim is made due to your joint failing .
Ubique
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You’ve jogged a memory there, the 500kW sets had parallel 240mm2 to the sync panel - up to six sets connected so 3MW max. The cables in & out couldn’t be terminated at less than 10deg. C in case the insulation cracked… Most of these installations (there were 52 sites) were done in an ambient daytime temperature of -31 to 35 deg.C in a Balkans winter, IIRC there were six Dantherm blown air heaters running night and day, it took 36 hours after the cable layers had finished to get them up to temperature prior to making off.
ajlelectronics
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The solder is and should always be secondary to the mechanical joint.
mtt.tr
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I started using the non insulated splice crimps worth consideringI am an auto electrician - nothing wrong with crimps at all.
I do tend to solder wiring splices allot thou - it is just easier and neater with heatshink - has a more OE look for a "hidden repair".
I got a real thing about adhesive lined heatshrink.
I think with the crimps most of us use, the cable outer is crimped and held too, putting the bulk of the loads through the outer. The conductors are still flexible at that point,mso last a good long time.m
Solder it, and the solder wicking up the conductors puts the point of flexing somewhere up inside, probably away from wherever the outer might be supported - so the conductors break inside an apparently sound outer cover.
Age of my cars, I'm well outside any dealer network worries about style of any repairs . But I want the repair to last.
Solder it, and the solder wicking up the conductors puts the point of flexing somewhere up inside, probably away from wherever the outer might be supported - so the conductors break inside an apparently sound outer cover.
Age of my cars, I'm well outside any dealer network worries about style of any repairs . But I want the repair to last.
sako243
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Doesn't mean they won't benefit from it, it's not just down to the connector to provide the strain relief but also clamps on cables etc.
MetalMonkey
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Probably getting in to the semantics, but strain relief would typically be at the point where a cable enters a device (be it connector, enclosure etc) otherwise it is cable support.
You can get an optional bolt on strain relief bracket for them, but I've never seen one in use in the wild it has to be said.
Most of the time the connector will be left hanging, or with one half bolted, so the pins themselves are subject to at least some strain and movement (and they do have a bit of wiggle in the housing) - which is why its always best to crimp them rather than solder.
That being said, I've soldered them before in a non critical application and they were fine.
The last set of jump leads I made up I crimped a 350A one in the middle so I could plug it directly in to a vehicle - borrowed works crimp tool which cost more than the car the leads were for.... Not a practical DIY option.
Although that was well before the advent of cheap Chinese hydraulic crimpers, which would be the way I'd probably do it now.
Erie Fred
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Would you like a job sir ?
Working upside down of course, smaller wire as well....about 25mm stripped size.
Qty (12) of them....should be a Piece O cake.
4500 hp has to get to the wheels somehow......
Single core 300mm2 cable is only about 30mm diameter so not much smallerWould you like a job sir ?
Working upside down of course, smaller wire as well....about 25mm stripped size.
Qty (12) of them....should be a Piece O cake.
4500 hp has to get to the wheels somehow......
sako243
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If its getting hot enough to melt solder then arguably the connection isn't big enough.
Classic case where cable/joint is underspecced so things start heating up which then cause the resistance to increase which further heats things up leading to failure. The whole run should be specced so the continuous load can be comfortably met without significantly heating up any portion of it, you can carry higher currents but they need to drop back down to let things cool off. If they don't then you need to up the cable run and joints accordingly because that's the new norm.
Erie Fred
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So you'll be applying ?....
