Dangerous car battery jumper cables - Page 1
Forum section: electronics / general

author: fubar.gr
author_rank: Unknown
timestamp: February 12, 2015, 12:58:03 pm
content: I bought these jumper cables really cheap.Nice thick cables, capable of handling 1200A, according to the writing on the packageBut on closer inspection:The actual copper is less than 10% of the cable thickness!I measured the resistance of each cable and it was 58mOhms, or 116 mOhms total for both cables. These cables can't handle more than 20 Amps tops.

author: electr_peter
author_rank: Unknown
timestamp: February 12, 2015, 01:26:33 pm
content: Thanks for providing real example of crap/fake jumper cables. Is it possibly to deduce cable quality without destructive testing? Would any of these tests (4 wire mili-ohm reading, weight, flexibility, buoyancy) be good enough to indicate fake cables?Topic about jumper cables was disccused recently here:https://www.eevblog.com/forum/chat/jump-starting-a-car/EDIT: just noticed that crimp connection is a POS. Is it even a real copper (looks like aluminium)?

author: PeterFW
author_rank: Frequent Contributor
timestamp: February 12, 2015, 02:04:58 pm
content: Quote from: electr_peter on February 12, 2015, 01:26:33 pmCould be steel, i had a few chinese cables made of steel.Greetings,Peter

author: Yago
author_rank: Frequent Contributor
timestamp: February 12, 2015, 02:25:35 pm
content: Manufactured at The crazy World of Arthur Brown!

author: amyk
author_rank: Super Contributor
timestamp: February 12, 2015, 03:11:15 pm
content: They'd probably survive 1.2kA for a second or two... what do you estimate is the diameter/area of the conductor?

author: Excavatoree
author_rank: Frequent Contributor
timestamp: February 12, 2015, 03:30:37 pm
content: I'm not sure they exist outside of the US, so our non US readers might not know what I'm talking about, but the insulation looks like the stuff from which they make Circus Peanuts.

author: senso
author_rank: Frequent Contributor
timestamp: February 12, 2015, 03:35:49 pm
content: There is no destruction involved, just pull one of the plastic sleeves that cover the wire crimp and look.Some time ago I paid 140€ for a 400A 6m jumper cable, and man its heavy, and yes, there is nice thick cooper inside them.The basic rule is simple, if its cheap its crap.

author: tszaboo
author_rank: Super Contributor
timestamp: February 12, 2015, 04:14:18 pm
content: S owe have fake fuses, fake jumper cables and 20% of pilots who have no idea what to do when ship happens. Great.

author: SeanB
author_rank: Super Contributor
timestamp: February 12, 2015, 06:56:26 pm
content: Have used those, and seen them melt as well. The insulation is foamed polyethylene with an outer skin, so it is lightweight. Melts at about 70C as well, and yes the core is copper coated steel, just like the clamps.I reused the clamps with better cable, now the cable does not heat up at 200A but the clamps do.

author: fubar.gr
author_rank: Unknown
timestamp: February 13, 2015, 10:46:21 am
content: The total diameter is 11.5 mmI can't tell the actual copper diameter without taking it apart, but by the looks of it I'd say it looks like 2.5 mm2The total cable resistance at 100+ mOhms is an order of magnitude more than the battery internal resistance and the resistance of the starter motor combined.This means that only a third or so of the rated 12 Volts will actually reach the starter motor.

author: Psi
author_rank: Super Contributor
timestamp: February 13, 2015, 11:41:06 am
content: I truly laughed out loud when i saw that picture.

author: richard.cs
author_rank: Super Contributor
timestamp: February 13, 2015, 01:50:13 pm
content: Ah, "charging cables", the charge current being simply and reliably limited by the crappiness of the cables, 30 minutes later you can start the car. Also note the poor crinmping technique, the pressure on the metal-metal contact will be low because it's just folded back over the insulation.

author: madires
author_rank: Super Contributor
timestamp: February 13, 2015, 02:03:44 pm
content: Quote from: fubar.gr on February 12, 2015, 12:58:03 pm1200 Chinese Ampere = 12.00A

author: dannyf
author_rank: Super Contributor
timestamp: February 13, 2015, 02:07:02 pm
content: QuoteHigh cost of low prices.

author: xrunner
author_rank: Super Contributor
timestamp: February 13, 2015, 02:11:07 pm
content: Yep, that doesn't surprise me at all. There's a lot of cheap ass shit coming in from you know where. I've seen bad connections like that on smaller test leads, however, in order to see how bad the connection really is you have to cut the plastic off with a knife because its a sealed plastic connector. They are hiding a whole lot of shit from people's eyes.That gives me an idea for a new thread - The worthless connection thread - or something like that. Look for it ...

author: cosmicray
author_rank: Frequent Contributor
timestamp: February 13, 2015, 02:18:00 pm
content: How long would the maker of those cables last if they were sold in China. Are those intended for export only ?

author: SeanB
author_rank: Super Contributor
timestamp: February 13, 2015, 03:21:45 pm
content: Export only. Remember what happenned to the makers of that melamine contaminated baby formula who sold it inside China. they became organ donors, and the family was sent the bill for this as well.

author: dannyf
author_rank: Super Contributor
timestamp: February 13, 2015, 03:29:46 pm
content: QuoteThere are countless scam artists whose business models rest on consistently scamming lots of people, one at a time.Yes, tons of such stuff is sold in China too.

author: Galenbo
author_rank: Super Contributor
timestamp: February 16, 2015, 10:45:42 pm
content: Quote from: fubar.gr on February 12, 2015, 12:58:03 pmThis makes them safer than the "better" ones.Garage owners have better thicker cables, but don't put them in the hands of the ordinary guy.Due to the bigger resistance, when short circuited, the source car isn't damaged and the sink flame is much weaker.Sure the car won't start on these cables, but the battery will charge (with a limited current, witch is better)

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 19, 2015, 05:10:14 pm
content: Just to answer the earlier question about a non-destructive test. Weigh them. Accuracy is not required. You can tell when you pick them up that they are crap. This does presume that you have calibrated at least once in your life by picking up good cables.

author: German_EE
author_rank: Super Contributor
timestamp: February 19, 2015, 09:56:32 pm
content: Well, one thing is explained. I did a jump start last year and the cables melted plastic all over my front bumper, they were probably of similar quality.

author: jlmoon
author_rank: Unknown
timestamp: March 02, 2015, 09:21:06 pm
content: I think we need to put them to a Failure Point Analysis, just to see what they can handle and how long.

author: dannyf
author_rank: Super Contributor
timestamp: March 02, 2015, 10:13:29 pm
content: QuoteHigh cost of low prices.

author: shanky887614
author_rank: Contributor
timestamp: March 02, 2015, 10:54:04 pm
content: 16/25mm is much betterthose cables are dangerous measuring end to end on a socket circuit is usually under 1ohm

author: tom66
author_rank: Super Contributor
timestamp: March 02, 2015, 11:36:05 pm
content: Quote from: dannyf on March 02, 2015, 10:13:29 pmHigh cost of customers not having the knowledge to determine if a product is shit.I have discovered Halfords (UK car parts shop) selling fake car fuses. Pack of five for £2.99. Sure, not expensive but you see a brand name and you expect that you can trust them. Nope. This importing deluge needs to be seriously looked at as there are so many counterfeit/fake/dangerous goods entering this country it's forcing legitimate suppliers out of business.

author: BradC
author_rank: Super Contributor
timestamp: March 03, 2015, 12:43:10 am
content: Quote from: shanky887614 on March 02, 2015, 10:54:04 pmI have a 4M set I made from some surplus 32mm solar/welding cable. They have no problems starting a 7L marine diesel with no local battery but they weigh a *lot*. I would expect the result of shorting them is instant destruction of the source. They have fully covered clips.On the other hand, my brother had a cheap-o set not unlike the ones that started the thread. They had transposed the red and black clips on one end, so red cable - black clip. He proceeded to use my mothers Land Rover Disco to jump start his girlfriends Toyota Echo. He gave me a call to ask why the cables were getting so hot. The Toyota survived without issue, but the electrics (which are marginal out of the factory) in the Disco were never the same again.You get what you pay for. I priced a set of 32mm 4M cables from a boutique 4WD company and they were close to $500. Most of the "affordable" 2AWG sets I've seen in the flesh are a mixture of copper and aluminium wire.

author: calexanian
author_rank: Super Contributor
timestamp: March 03, 2015, 03:05:19 am
content: http://www.wireandcabletogo.com/1-0-Welding-Cable-Class-K.html?gclid=CMDL_ZuZi8QCFZJefgodDCMAggThats what I used for my jumper cables. You don't even need the battery in the other car. Just connect them up, turn the ignition, and you are on your way. I used some harbor freight welding ground clamps for it. Works great.

author: Zucca
author_rank: Unknown
timestamp: March 03, 2015, 10:11:16 am
content: They are high quality High Voltage Battery Cables for Hybrid cars... like Tesla's.....

author: tom66
author_rank: Super Contributor
timestamp: March 03, 2015, 11:35:36 am
content: Quote from: zucca on March 03, 2015, 10:11:16 amA Tesla is not a hybrid and you cannot jump the HV battery pack. You can jump the 12V battery which is needed if you get in an accident (as the high-voltage battery is disabled and will no longer charge the 12V.)

author: SeanB
author_rank: Super Contributor
timestamp: March 03, 2015, 07:25:24 pm
content: My jumper leads are the cheap clamps and 00 gauge PTFE covered cable. I have used it to jump start with a totally dead battery, and while the connectors smoked the cable did not.Did one night jump start an ambulance using the ground power unit, luckily they were close enough so I did not have to move the truck, just unwind the 28V leads and jam the cheap jump leads into the socket ends on the cabling. Lighting on the ambo went from dim to bright instantly, and it started on the first turn of the starter. 24V battery was quite happy with 28V, though I could not see any current draw on the ammeter, full scale is 8kA. Plug some aircraft into it and you do get the peak coming very close to that. Funny enough not big aircraft either. You just need a big jet engine with a starter/generator bolted to the front of it. It can charge at that rate too.........

author: macboy
author_rank: Super Contributor
timestamp: March 04, 2015, 05:29:08 pm
content: Quote from: dannyf on February 13, 2015, 03:29:46 pmA Chinese-Canadian coworker of mine (a software engineer) left China due to the ethical environment there, or lack of ethics. She said there is a saying there, something like, "If the river istoopure, there won't be any fish". That really explained a lot for me, but excused nothing.

author: Muny
author_rank: Contributor
timestamp: March 05, 2015, 11:02:57 pm
content: The insulation on that looks like a hotdog...I'd eat it!