60A connectors - Page 1
Forum section: electronics / projects

author: luky315
author_rank: Regular Contributor
timestamp: September 22, 2015, 02:02:18 pm
content: How would you connect a 25mm² cable carrying 60A @ 12V (maximum) to a 70µ Cu (4Layer) PCB in a harsh ("Off Highway") environment ?It is a low volume project, therefore expensive tools (e.g. for the WE High Current Terminal Blocks) are not an option.

author: fcb
author_rank: Super Contributor
timestamp: September 22, 2015, 02:06:54 pm
content: I'm using Wurth 7460408's on a 32A project - they do some bigger ones also. Pretty low cost.

author: tszaboo
author_rank: Super Contributor
timestamp: September 22, 2015, 02:19:40 pm
content: M5/M6 Screw, washer, PCB, Washer, shakeproof washer, M5/M6 nut, washer, crimp ring terminal, washer, shakeproof washer, nut, nut.Place a bunch of vias around the hole and keep enought space for the washer.Keep distance between the inputs big, in case they rotate.But I like the Anderson connectors for any other occasion.

author: max_torque
author_rank: Super Contributor
timestamp: September 22, 2015, 04:13:29 pm
content: It really depends on the environmental sealing requirements!For a non sealed approach, then Wurths Power Studs are perfect.if you need an IP6X sealed connector, things get a LOT more expensive.One thing i have done is to fully encapsulate the pcb and components in a hard epoxy potting compound, leaving the power studs rising up above the "surface" of the potting. I've used this for high current drivers / switches, where the pcb sits potted on a CNC alluminum block for heat transfer. In effect, the machined out block becomes half the enclosure.

author: HighVoltage
author_rank: Super Contributor
timestamp: September 22, 2015, 04:45:19 pm
content: For low quantity and hopefully enough space, I have used M8 screws before and it worked very well.Use some large diameter washers as well and lock-washers under the nuts.

author: jitter
author_rank: Frequent Contributor
timestamp: September 22, 2015, 04:46:11 pm
content: Quote from: luky315 on September 22, 2015, 02:02:18 pmI think the answer depends on what the end of the wire is going to look like. If you have to crimp on some terminal, it's going to require an expensive tool (should you not have it already).Or is a terminal already crimped on? If so, what's its size?I remember working on something that used L-shaped nickel plated copper profiles that were bolted onto a big pad on the pcb. The wire's ring terminal was bolted to the upright part of this profile. I think that for direct connection of the wire to the pcb, the pcb was not considered strong enough. The profile spread forces over a bigger surface. Something to keep in mind.If a single 25 mm2wire is not an absolute requirement, how about multiple thinner strands? Individually, they might be easy and cheap enough to connect to the board but together still be able to conduct the required current.

author: luky315
author_rank: Regular Contributor
timestamp: September 22, 2015, 06:07:46 pm
content: The 25mm² wire are installed (with an open end)I like the idea of dividing the strands and using 2 -3 connectors (6.3mm wire terminals or M6 screws)Has anyone installed the Wuerth Terminal Blocks without the appropriate Tool?

author: Monkeh
author_rank: Super Contributor
timestamp: September 22, 2015, 06:33:15 pm
content: Beg borrow or steal a crimper so you can put a suitable lug or a Powerpole on the cable.

author: nctnico
author_rank: Super Contributor
timestamp: September 22, 2015, 06:35:47 pm
content: I agree. Don't mess around with these kind of currents due to fire hazard and liability. Just get the right crimper and lugs! A decade ago I spent 250 euro on a crimper to do 4 lugs. I didn't want to solder in a car nor take the chance the solder connections would losen over time.

author: mzzj
author_rank: Super Contributor
timestamp: September 23, 2015, 08:08:30 am
content: Quote from: nctnico on September 22, 2015, 06:35:47 pmCheap&Cheerfull&Chinese crimpers seem to work fine if you dont make dozens of connectors per day. But the lugs have to be quality ones.Workable ones from personal experience:http://www.ebay.com/itm/6-50mm2-Crimp-Copper-Tube-Terminal-Crimping-Crimper-Tool-with-Hight-Quality-/231625352733?hash=item35edf2661dhttp://www.ebay.com/itm/16-Ton-Hydraulic-Wire-Battery-Cable-Lug-Terminal-Crimper-Crimping-Tool-11-Dies-/360798635074?hash=item5401464442Jaw fitting is less than perfect on the big hydraulic crimper but luckily I dont need that monster more than couple of times per year.For the pcb side I would be tempted to try soldering these despite "not for soldering"http://www.digikey.com/product-detail/en/7461098/732-3278-ND/2092196Kemppi uses fork connectorlookalikessoldered through pcb in many of their welding machines at least up to 150A or so.http://www.newark.com/multicomp/cbs-to-1806-ht/terminal-spade-fork-6-crimp/dp/14T22282 holes and pins per cable gives your more robust connection.

author: Jeroen3
author_rank: Super Contributor
timestamp: September 23, 2015, 08:25:06 am
content: With huge wire blocks. Such as Phoenix MKDSP.https://www.phoenixcontact.com/online/portal/us?uri=pxc-oc-itemdetail:pid=1932588&library=usen&tab=1

author: nctnico
author_rank: Super Contributor
timestamp: September 23, 2015, 10:40:17 am
content: Look at the MOQ and knowing Phoenix it will be pretty expensive. If it has to be pluggable I'd use a smaller dual row pluggable terminal block and use several contacts in parallel derated to 60% of max current.@mzjj: that crimper looks handy. I'm going to buy one!

author: tszaboo
author_rank: Super Contributor
timestamp: September 23, 2015, 10:59:37 am
content: Quote from: Jeroen3 on September 23, 2015, 08:25:06 amThat is not bad. 9 bucks at digikey. Do you need like special treatment of the cables to connect to these (ferrule maybe), or a bare cable can go into these and then secured with the screw?

author: Jeroen3
author_rank: Super Contributor
timestamp: September 23, 2015, 11:12:37 am
content: Always use ferrules. Better contact and more consistent result.

author: Stonent
author_rank: Super Contributor
timestamp: September 23, 2015, 03:58:48 pm
content: Anderson makes high current board mount connectors also. But I only see 13mm listed.http://www.andersonpower.com/us/en/products/sbs/index.aspx

author: eneuro
author_rank: Super Contributor
timestamp: September 23, 2015, 10:48:59 pm
content: Quote from: NANDBlog on September 23, 2015, 10:59:37 amThose connectors looks like were made for children toys25mm2 gives ~6mm in diameter wire, so for exactly the same shown below I've used.... 8mm in diameter copper pipes which had 1.5mm thick cylinder walls and was ~25mm long at it costs... almost nothing $0.30After crimping, additionally I've made at from 1.5mm hole and heated it to be able solder top of this connector from hole side.Drilled 6mm hole for M10 (10mm) screw and with additional spring support I believe it is capable for many amps in my custom welder transformer to make soft arc welding with thin electrode.Sorry, but those $9 connectors looks very crappy in comparision with my cheap crimped 8mm copper pipe, I've described and showed above and now testing in my arc welder.Of course it require extra "art" work, but... to pay at digikey, we have to also work, and for pennies we can make better connectors using pure copper pipe, vise, hammer and drill

author: CM800
author_rank: Frequent Contributor
timestamp: September 23, 2015, 11:05:41 pm
content: Here We GoI have used these type of connectors for power before on an inverter break out board project. They work like a charm.

author: ndzied1
author_rank: Contributor
timestamp: September 23, 2015, 11:41:55 pm
content: These guys will have something that will workhttp://www.meltric.comNot sure of the cost though

author: tszaboo
author_rank: Super Contributor
timestamp: September 24, 2015, 10:18:52 am
content: Quote from: eneuro on September 23, 2015, 10:48:59 pmSure, we will just tell the subcontractor to make the ends of the cables that way. That should be an easy document, onyl a few pages, and all the cable makers will love to do that.If Phoenix tells me that something is rated for that many amp, I believe it, without question.

author: eneuro
author_rank: Super Contributor
timestamp: September 24, 2015, 04:20:48 pm
content: Quote from: NANDBlog on September 24, 2015, 10:18:52 amWhen I want have something powerfull, before I put it into my high power circuit, I'd rather connect to ... spot welder output and test it before such failed connector will ruin my dayIn the case of 8mm in diameter copper pipe 1.5mm thick, estimation of connection area is easy: we have (8^2-5^2)*3.14/4~30mm2 of conducting copper crosssection area in such copper pipe, so it is more than 25mm2 wire we put inside, so we haven't got loses in this connector if we make it correct.Phoenix or what ever another company if they show such calculation I've shown above in the case of pure copper pipe, if their price will be competitive vs time needed to make such connector, maybe I could consider as an option, but those connectors looks so crappy in comparision to pure copper made, that I do not take their name-I need a numbers whicg could proove those things can be capable what they claim....Give me the numbers, not company name-I do not care about anything but numbersm because of physics works

author: tszaboo
author_rank: Super Contributor
timestamp: September 24, 2015, 04:43:36 pm
content: Quote from: eneuro on September 24, 2015, 04:20:48 pmDid you bother clicking on the link above?"Conductor cross section solid max. 35 mm²"

author: nctnico
author_rank: Super Contributor
timestamp: September 24, 2015, 04:48:26 pm
content: Quote from: NANDBlog on September 24, 2015, 10:18:52 amI agree about the DIY cable lug. Especially the solder is likely to creep out under pressure after a while making the connection go loose.Then again I also wouldn't trust Phoenix either. Those connector ratings are usually very optimistic and measured in optimal conditions; running 125A through four 1.6mm pins (!) is likely to get hot and affect the solder joints of the circuit board in the long run. I usually derate terminal blocks and connectors to around 60%.

author: ConKbot
author_rank: Super Contributor
timestamp: September 24, 2015, 06:03:38 pm
content: Quote from: eneuro on September 23, 2015, 10:48:59 pmSo, the OP needed to connect a high gauge wire to a PCB, someone linked a terminal block, which mounts to the PCB and takes solid, stranded or ferrule'd bare wire, and here we have a bunch of mental masturbation about how awesome a pipe smashed in a vice is and how shit the contact block is. One issue though. Regardless of how the lug is made, or attached (home made, purchased, solder, crimp). This doesn't solve the OP's problem of attaching it to a PCB. You cant bolt lugs to a PCB, it will creep, and contact pressure will be lost. So instead of a terminal block, you have to use either a pcb mount stud (http://www.digikey.com/en/product-highlight/w/wurth-electronics/press-fit-power-elements) which the OP nixed because of tooling cost, or some other solution to attach a lug to a PCB.So a home made lug isnt even a solution, let alone a better solution or the best solution.

author: eneuro
author_rank: Super Contributor
timestamp: September 24, 2015, 06:48:12 pm
content: Quote from: ConKbot on September 24, 2015, 06:03:38 pmWe haven't got any picture of OPs PCB and its connection area, but maybe he could first think what kind of connector will be used and than try to optimize PCb design to be able attach something capable to survive high currentI haven't got problem with that, because of I know before PCb design what kind of connector I will use ...Image is worth thousand of words, but it looks like pople are strugling use old school good digital cameras o make one shot of PCb etc, else such brain storms can lead to different conclusions, while PCb design might be wrong for high current application from the begining and choosing even best connector doesn't help...BTW: W few oz PCB tracks are another story and when we calulate how much copper is in their cross section area (regardless how wide they try to make those "power" tracks) , than... it might look like those manufacturers use superconduction effects to provide decent currents at such low amount of copper and it seams that connectors manufactures marketing claims goes into the same direction by bending laws of physics in their products

author: eneuro
author_rank: Super Contributor
timestamp: September 24, 2015, 07:18:14 pm
content: Quote from: luky315 on September 22, 2015, 02:02:18 pmNow lets calculate copper trace width 2 oz (70 µm) x 4 layers = 280 µm = 0.280 mm connected to 25mm2 cable25mm2 / 0.280mm = 89.3 mm ~ 90 mm = 9 cmReally, do you have 9cm width copper traces on your 4 layer 2 oz PCB while you try connect 25mm2 copper wires to them?Which is width of your traces on this PCB for 60A?

author: Monkeh
author_rank: Super Contributor
timestamp: September 24, 2015, 07:38:19 pm
content: Quote from: eneuro on September 24, 2015, 07:18:14 pmYou don't need 25mm² of copper on a PCB to handle 60A. Next daft comment?

author: mzzj
author_rank: Super Contributor
timestamp: September 24, 2015, 08:10:33 pm
content: Quote from: eneuro on September 24, 2015, 07:18:14 pmhttps://dl.dropboxusercontent.com/u/93888484/IMG_3856.jpg2-layer "pcb" with 250mm wide 1000um copper connected via 20pcs 2.5mm copper pins to 500mm2 bus bar

author: eneuro
author_rank: Super Contributor
timestamp: September 24, 2015, 09:59:59 pm
content: Quote from: Monkeh on September 24, 2015, 07:38:19 pmIt depends if we use solid wire or copper pipe and high current duration.60A/25mm2= 2.4 A/mm2 slightly overkill and probably 12mm2 could be fine with 5A/mm2.Anyway, for spot welder I've used 15mm in diameter copper pipes which gives us at 1mm walls ~ 44 mm2 cross section copper area, and at short-circuit with M10 screw heated by resistance very hot red, those copper pipes quickly got hot, so I do not expect 1000A currents there (I'll have to use Hall sensor to measure this current), but when we take even 600A/44mm2 ~14A/mm2, so three times more than 5A/mm2, without water cooling you could easy cook egg on those thick copper pipes, so what is your estimation of needed A/mm2 for contonous operation at ideal 20*C air temperature without additional water cooling?Update: Looking into those numbers hereCopper wire figureswe can find for 35mm2 wire note:Quote200A/35mm2 ~6A/mm2...So, for spot welder my estimations looks good.I've used 25mm2 AWG 4 5.1mm in diamater with connector shown above for soft arc welding and with 0.800 mOhm/meter, at 150A we have ~18W loss per meter, so not so bad.150A/25mm2 ~ 6A/mm2 not so bad...I used copper pipes for some reason-I will be able drill holes to mount water or air cooling inside those thick pipes, but I've no idea howto cool 4 layer PCB - nitrogen?

author: Monkeh
author_rank: Super Contributor
timestamp: September 24, 2015, 11:31:16 pm
content: Quote from: eneuro on September 24, 2015, 09:59:59 pmNeither is involved on a PCB.Next unrelated post?

author: ez24
author_rank: Super Contributor
timestamp: September 25, 2015, 01:12:42 am
content: Quote from: Monkeh on September 24, 2015, 11:31:16 pmAn University (5 students and a teacher) discovered the VW software cheating. I am sure there are some amps in there somewhere.

author: Jeroen3
author_rank: Super Contributor
timestamp: September 25, 2015, 05:39:30 am
content: I thinkeneurois a service or repair guy. Where it is allowed to bodge a solution to get running again as fast as possible to delay a permanent solution for when downtime is allowed.For anything that has to run without a repair guy, get proper terminal blocks or mounting poles.

author: luky315
author_rank: Regular Contributor
timestamp: September 25, 2015, 06:24:41 am
content: I have decided to use the WE High Current Terminal Blocks (not yet sure which one but the representative is visiting next week) and borrow the necessary tools.If you allow for 20°C temperature rise a 10mm trace on all 4 Layer is more than enough, the more critical point is the connection to the TO-220 FET.But 60A is only the peak current and I monitor the PCB and heat sink temperature so it should be ok.

author: eneuro
author_rank: Super Contributor
timestamp: September 25, 2015, 09:24:44 am
content: Quote from: luky315 on September 25, 2015, 06:24:41 amStill you didn't specified RMS current in your application, sp we can only guess...If it were AC 0.707*60Amax ~42 A in average, so with 10mm width 2oz 4 layer track we have 10mm*0.28mm~2.8mm2, so we get 42A/2.8mm2-15A/mm2which doesn't look great, but for running in not continous mode maybe it will work with thermal shutdown protection...It is all about math and physics works, so do not try bend laws of physics in your design, because of sooner or later it will fail

author: tszaboo
author_rank: Super Contributor
timestamp: September 25, 2015, 11:53:16 am
content: Quote from: eneuro on September 25, 2015, 09:24:44 amYes, I guess the TO220 which can handle 75 A, including the few micrometer thick bond wire inside the package, just breaks the laws of physics.

author: eneuro
author_rank: Super Contributor
timestamp: September 25, 2015, 08:49:50 pm
content: Quote from: mzzj on September 24, 2015, 08:10:33 pmYep, this is what high power equipment needsTo make good durable connector we need copper, steel, grinder, drill, vise, hammer and... creativity with laws of physics in mindLet RC toys fans use those expensive crappy factory made connectors-high current likes copper, not plastic to flow

author: Monkeh
author_rank: Super Contributor
timestamp: September 25, 2015, 09:03:17 pm
content: Quote from: eneuro on September 25, 2015, 08:49:50 pmAnd let people with a clue and a reputation to protect use appropriate connectors which are engineered, not hammered out of pipe.

author: eneuro
author_rank: Super Contributor
timestamp: September 25, 2015, 10:04:52 pm
content: Quote from: Monkeh on September 25, 2015, 09:03:17 pmFortunatelly, electrons have no clue who designed circuit tracks and do not care what tools were used, but... they will like flow more likely where low resistance paths exists

author: Monkeh
author_rank: Super Contributor
timestamp: September 25, 2015, 10:05:56 pm
content: Quote from: eneuro on September 25, 2015, 10:04:52 pmYou need to tone your ego down and ponder why products don't come with lugs made of copper pipe. I mean, it's so cheap and easy, and a really brief test showed it worked! Must be the best way!

author: nctnico
author_rank: Super Contributor
timestamp: September 25, 2015, 10:33:56 pm
content: Quote from: Monkeh on September 25, 2015, 10:05:56 pm+1 The way that cable is connected to the steel looks like crap. Are those copper wires 'welded' to the steel? @Eneuro: Please do yourself (and others) a favor and look at how the battery in your car is connected to the chassis: crimp a proper ring lug on a cable and bolt it to the chassis. Easy and simple. No messing with copper pipes or other half assed solutions to connect a wire which can carry a high current to a chassis. If that chassis must serve as a ground then you should connect the individual parts with additional ground straps. Again: look at a car for an example; you'll find various ground straps between the engine and the chassis.

author: eneuro
author_rank: Super Contributor
timestamp: September 25, 2015, 10:52:38 pm
content: Quote from: nctnico on September 25, 2015, 10:33:56 pmWhich one? Copper 25mm2 strand wire is connected ONLY to 3mm in diameter solid copper wire, using another copper pipesSteel in this transformer is used only for magnetic circuitBetter invest in copper, than crappy plastic connectors, while copper is 100% reusable after recycling

author: nctnico
author_rank: Super Contributor
timestamp: September 25, 2015, 11:39:50 pm
content: OK now I see those are transformer windings you are trying to connect. Better put some description to your pictures for easy understanding. That flat piece of copper tube still look crap. I'd put some ring lugs on the transformer wires and bolt the whole thing together.

author: Monkeh
author_rank: Super Contributor
timestamp: September 25, 2015, 11:54:06 pm
content: Quote from: eneuro on September 25, 2015, 10:52:38 pmDo you really still not see the difference between a piece of thin-wall copper tube and a crimp lug?And as for those 'crappy plastic connectors', err, the plastic is a housing. They are fully capable of terminating large cables and carrying substantial current, and I'd trust them more than your bodges. The small pin diameter is only a concern if it's allowed to get hot, and it uh, has a giant heatsink called a cable attached to it.

author: eneuro
author_rank: Super Contributor
timestamp: September 26, 2015, 07:50:41 pm
content: Quote from: nctnico on September 25, 2015, 11:39:50 pmThis was not pernament solution since, so decided to make connector which I will be able remove if not wantedAnyway, it might look not so strong, but, maybe because of bulky M10 mm screws were installed. When made measurements of this "thin" copper tube it has 0.5mm walls and has flatened width more than 20mm (~23mm), so cross section area is: 0.5mm *23mm *2= 23mm2 , so easy 150A @ <7A/mm2Together with this thing easy to make low duty cycle soft (spot) weldingAll crossection areas of connectors used were estimated to keep the best possible connection for 25mm2 strand copper wire

author: Monkeh
author_rank: Super Contributor
timestamp: September 26, 2015, 07:52:27 pm
content: Quote from: eneuro on September 26, 2015, 07:50:41 pmIt's a connector, it's not about just CSA..You really should find another thread to contaminate with your bodge jobs.

author: eneuro
author_rank: Super Contributor
timestamp: September 26, 2015, 07:59:44 pm
content: Quote from: Monkeh on September 25, 2015, 11:54:06 pmNope, this copper pipe has 0.5mm walls and as calculated above 23mm2 of copper for high current.Anyway those 1.5mm copper pipes mentioned above (detailed view below before mounting wire insode) with 4mm strand wire after some vise and hammer and drill work could be capable of 60A continous for sureAfter some art work, no worries, it was tested during soft spot welding a while ago and nothingBTW: Do you have hammer and vise in your toolbox?It is easy make durable connector, it is not rocket science only basicneededUpdate: It was my last post in this thread, while just finished right now upgrade of my (spot) welder and I've no problems with high power connectors at allPhysics works.

author: Monkeh
author_rank: Super Contributor
timestamp: September 26, 2015, 08:02:25 pm
content: Quote from: eneuro on September 26, 2015, 07:59:44 pmLet's see how long your bare thin-wall copper connectors last in a road salt environment with wide temperature swings and vibration. Brief exposure to high currents is not much of a test.

author: Jeroen3
author_rank: Super Contributor
timestamp: September 26, 2015, 08:47:09 pm
content: He doesn't need to do a good job. He doesn't sell those cables.

author: Monkeh
author_rank: Super Contributor
timestamp: September 26, 2015, 08:51:41 pm
content: Quote from: Jeroen3 on September 26, 2015, 08:47:09 pmHe seems to be trying really hard to.

author: nctnico
author_rank: Super Contributor
timestamp: September 26, 2015, 09:23:34 pm
content: Quote from: eneuro on September 26, 2015, 07:59:44 pmA hammer is the worst tool for crimping. If you hit something with a hammer it will flex back so in case of a crimp the wire will get loose after a while; I have seen this happen because you are not the only one who is wrong in thinking a hammer can be used as a crimping tool. Sometimes the intern teaches the coach!A real crimp tool puts a lot of (properly directed) pressure on a crimp connection in order to form a cold weld (there is a term for it but it doesn't come to my mind right now). You can't do that with a simple vise.

author: sarepairman2
author_rank: Frequent Contributor
timestamp: September 26, 2015, 10:52:11 pm
content: im with en euro on this, unless its some kind of high reliability satellite shit who gives a fuck? if it goes bad, just wack it with the hammer.or better yet, braze it.god damnelectromechanicalengineers.........the reason why they dont hammer shit out of copper is because its more profitable for the seller and easier for production people to use crimp tools instead of hand making a connector for things on an assembly line.for something you make a few of? YEA RIGHT.crimps you buy will be engineered to a price, some heavy copper shit you hand make at home is probobly actually gonna be better. just not as easy to implement.pretty much everything you figure out how to make and not try to engineer down to a price is gonna have better performance then something you can buy, unless it requires custom asics lol$_$

author: Monkeh
author_rank: Super Contributor
timestamp: September 26, 2015, 11:17:51 pm
content: Quote from: sarepairman2 on September 26, 2015, 10:52:11 pmBecause it work hardens and cracks.

author: sarepairman2
author_rank: Frequent Contributor
timestamp: September 27, 2015, 12:47:57 am
content: i wanna see someone work harden and crack a copper pipe making a connector

author: dom0
author_rank: Super Contributor
timestamp: September 27, 2015, 01:06:13 am
content: What kind of tard fest is this?!

author: Nerull
author_rank: Frequent Contributor
timestamp: September 27, 2015, 02:55:49 am
content: There was a recall awhile back of over a million rooftop solar panels which had used copper lugs on the ground connections.It turns out that copper, while an excellent conductor, doesn't stay that way when exposed to the elements and the connections were failing. Who could have known?

author: Siwastaja
author_rank: Super Contributor
timestamp: September 27, 2015, 06:41:15 am
content: Don't you see it? He's clearly a kid. Look at his other (almost always off-topic, and hard-to-read) posts. But he's doing things all the time. Interesting things. He's a kid really devoted in electronics and doing nice things with just a hammer. We have all been there. And most of us have had, or still have, problems with attitude. I'm sure he will learn. It takes time to really accept that engineering is not quick and trivial. I've been there, too. And I still make sure I try all possible shortcuts to make things as simple as possible. I also tend to "DIY" as much as possible. I just stopped lying to myself that well-documented physical phenomena do not exist and a hammered DIY crimp lug is as good as or better than a commercial lug.The world looks different when you can only build something using the $5 pocket money and you are only liable to yourself and your parents. It's also more fun; you are just a hobbyist and can whack a connector with a hammer, and heck, it'll probably work just fine due to:(1) short life; the project is a hobby project, it will be used for a few months and then it's tossed(2) easy environment (indoors)(3) just the probability: there is only one, and it will run limited hours. 1% failure rate may not be ever seen. Commercially, it would be a catastrophe.To most of us, it's a no-brainer: if you are designing a commercial (even small-scale) product, and need a connector, you look at the catalogs from reputable connector-makers for one that meets the specifications such as maximum current. Then you look at the price, and if it's not prohibitive, you have everything set in minimum amount of time.Whacking something with hammer is sometimes needed; although it doesn't solve the original question at all, as others have pointed out -- eneuro is just doing a DIY lug, and lug is clearly just one part of the solution. The question was how to connect it to a PCB. DIYing a lug, anyway, doesn't make a lot of sense unless you are REALLY broke or in a MacGyver type emergency. But I would be interested in how eneuro would answer to the original question, i.e., connect the wire to the PCB.

author: SeanB
author_rank: Super Contributor
timestamp: September 27, 2015, 07:49:50 am
content: The common large crimp lug starts off as a copper pipe in any case, just generally a thicker walled one, and is annealed after it is punched and formed to relax the metal, then it will be further processed like cleaning and coating prior to assembly. Smaller ones are a copper alloy or brass sheet which has similar treatment. Cheap lugs omit the expensive annealing and cleaning, just punch and form, then plate ( sometimes plate first, leaving copper edges, or even omit the plate totally), then assemble to the plastic crimp outer.To mount to a board at 60A is always difficult, you will be using either a very expensive PCB mounted screw connector, and a bootlace ferrule on the stranded wire, held in a clamp cage. Only reliable method, a bolted connection will fail, unless you use a riveted bolt which has a thin wall PCB side which is first riveted to the board, then is soldered, so that it is physically compressing the board, the solder providing more environmental protection to the joint than electrical connection. then you use a pair of conductive washers on the lug and tighten to a controlled torque, no split washer, no nylock nut but a controlled stretch of the bolt stud to get the right clamping force for long life. Drawback is you __NEED__ to use a torque wrench to assemble, and you only have a very limited number of disassembly cycles before you have to replace the stud.

author: cs.dk
author_rank: Unknown
timestamp: September 27, 2015, 08:15:09 am
content: What is the problem using nylocks? We do that all time at work, with this type of PCB stud:

author: SeanB
author_rank: Super Contributor
timestamp: September 27, 2015, 09:10:10 am
content: Nylock has issues with torque, unless you add a correction factor to the torque, and use a new nut each time it is undone. Otherwise the contact force the second time will be too high, as the nylon has deformed with the first use, so accepts a lower torque to turn, leading to increased stress on the stud thread. A combination of worn stud, high torque and a stress raiser on the cut thread of the stud ( those are a cut thread, not a rolled one which is stronger) means it will very likely snap off flush with only a moderate pull on the cable end, without having enough tension to pull the stud out of the board or delaminate it.Check with the supplier, and they will specify a maximum torque value and the correct nut to use with them as well. As well a nylock will hide the fact that there has been cold flow of the stud or terminal lug, just by the static grip of the insert. If there is no vibration there is no need to use a nylock, a regular nut is as good and will work even in moderate vibration environments, nylock is not used on connecting rod studs, just a regular nut with the stud tension always being enough to provide clamping force.

author: tszaboo
author_rank: Super Contributor
timestamp: September 27, 2015, 09:13:07 am
content: Quote from: eneuro on September 26, 2015, 07:59:44 pmYEP, I rather spend 9 EUR of someone else's money on something, than doing anything with a hammer.Try getting an UL recognition on your copper pipe. Try drawing it on a devices schematic. Try writing a document describing how to make it. Because guess what? Even thogh I know how to crimp a cable, I usually refuse to do it, and send a RFM to a different department of the company to make it. Engineers cannot be bothered to make this bodge. Time is money, and making crimps is not efficient usage of time. We have trained people to do it.Engineering works differently. It is OK to order something from the other side of the world, we dont have to throw something together at home. It is OK to order a 500 EUR crimp tool if you need hundreds of crimps, actually it is OK to order one if you absolutely need 10 and there is no other way to PROPERLY make it.A DMM is not the tool to be used to measure a crimp. Seriously, you are talking about something you have no idea about, and you should concentrate on absorbing information before you spit it.

author: eneuro
author_rank: Super Contributor
timestamp: September 27, 2015, 09:53:51 am
content: Quote from: Siwastaja on September 27, 2015, 06:41:15 amThere are endless possibilities and always before I will try connect wire to PCB I will think first if maybe I could use power mosfet heatsink as connector like in this ZVS driver, where copper pipes smashed at ends can be connected directly to PCB under mosfet drain (heatsink) and riveted to PCB additionally colled with water or minerl oil to keep this copper pipe at low temperatures, since induction heating will heat up this a few turns split air transformer primary?Anyway, we have to connect sometimes power source (12V car battery in this case) so in the case of double layer prototype PCB I've used automotive connectors... soldered at the edges to both sides of PCB and double layer PCB has a fwe mm power tracks on both sides so for a few amps this easy to integrate with other similar connectors is fine.For high power we could easy use in similar way edge of pcb with viases, (eg. 5mm x 5mm of copper padds on both sides gives us vast area of 50mm2 cross section area to provide current to connectors) and solder to both sides copper plates connector (eg. similar to this I've shown but bigger more powerfull) than screw connector with wire. Rivet througth PCB to ensure in some disaster temperatures solder will not flow away, eg, duing soldering in oven and here we goWatch this "Poors mans version of Ohms Law" by prof. Walter Lewin at can help you be more creative, and maybe help find better solutions than other crappy connectors available on the market8.02 Electricity and Magnetism Lec 09: Currents, Resistivity and Ohm's LawNote: In final product those connectors are spot welded to do not overheat PCB during soldering, while they have significant thermal mass and decent heat needed to solder them-of course not those tiny ones I've shown on photo above-I'm talking about spot welded high power connectors.

author: mzzj
author_rank: Super Contributor
timestamp: September 27, 2015, 11:49:16 am
content: Quote from: SeanB on September 27, 2015, 07:49:50 amI'd say its way more common to see disk springs aka belleville washers to provide constant preload on the joint. No problems with stud stretching and it's reusable.

author: eneuro
author_rank: Super Contributor
timestamp: September 27, 2015, 12:46:10 pm
content: Quote from: Siwastaja on September 27, 2015, 06:41:15 amYes, you nees study mechanics, electronics, physics and chemistry when you want to be successfull inventor like meThis is oryginal high current connector from my car starter battery (rated 600A for Peugeot 1.4HDI engine, I bought from manufacturer in France and since I'm the only one owner of this car no chance there were any service work or issues with this connector within 200000km I've in this car without any engine failure).Look carefully and yes, it is crimped and... soldered from connector side, so... yes I've made this photo for myself, since I'd like to add here Hall effect current sensor and needed this image to estimate needed hole size in PCB I'm working on...As you can see I've also added custom connector 2.5mm2 for battery charger, while I do not use of course this crap available on local market, but my own with... of course Hall effect sensor for current sensing...and thanks to this cheapy connector I do not have to use crappy ones manufactures at low cost with their battery chargers ... not capable to survive accidential engine start

author: SeanB
author_rank: Super Contributor
timestamp: September 27, 2015, 12:56:57 pm
content: I know, but they tend to be something not exactly common in most stores. Just ordered some though, at 9p each. Came out to 50p each after DHL delivery, and they had a MOQ of 500 units. Not really too bad though, as i use them in spring packs of 48 units, so now have 8 spare packs. The old ones were worn out, and the local ones are too variable in spring constant and height so bought direct from the UK.Smaller ones are nice though for this use you will have to specify the Belleville washer and a backing steel washer as a spreader between the washer and the softer copper lug to even the load so it is not just the periphery, and tighten till the washer is a predetermined compression, probably by using a low initial torque and then a predetermined turning angle to get to the desired compression and clamp force.Hand tight then 90 degrees works for a lot, though the ones I am installing have a specified float after full compression of between 0.2 to 0.5mm, to get them running in a non fatiguing regime.

author: SeanB
author_rank: Super Contributor
timestamp: September 27, 2015, 01:03:55 pm
content: Quote from: eneuro on September 27, 2015, 12:46:10 pmThe battery wire has solder there more for environmental protection, to keep battery acid from wicking up into the connector making it high resistance. Don't worry, it will corrode down the wire soon enough unless you keep it acid free. The small connector I am familiar with, I use them often enough, and have a crimping tool which works well on them. Not the steel plate one, but a proper ratchet crimp tool. For the 2.5mm I can also use another tool, an Amphenol one meant to do circular bayonet connectors, but where the dies are fine on those terminals. As the terminals are tinned they work well on battery use, as they tend not to corrode though the wire will.

author: johansen
author_rank: Super Contributor
timestamp: September 27, 2015, 04:03:05 pm
content: 1/4th inch copper refrigeration line, in my mind, does have sufficient sidewall thickness to be used as a crimp, provided you use a proper crimper. you can make such a crimper yourself by drilling a 1/4th inch hole in a block of steel, then drilling an 1/8th inch hole through the hole at a 90 degree angle. find two 1/8th inch diameter pins, grind the ends smooth and round, put the pipe in the hole, put the block in the vice, press the pins into the joint. pull the pins out, rotate the connector 90 degrees, move it 3/8ths of an inch axially along the pipe and press it again.there are professional hand crimpers that drive 4 pins into the lug together, and guess what.. the connector is 99% copper, they are called seamless copper lugs