Connecting Arduino Uno to car's fuse side pannel - Page 1
Forum section: electronics / general

author: tiofilo75
author_rank: Contributor
timestamp: August 02, 2012, 11:14:53 pm
content: Hello everyone, so I have this project in mind where I want to use a ping sensor along with an LCD to measure distance when I am backing up with my car. I plan to hook it up to an empty fuse slot which I have measured with my multimeter and it is outputting 12V. The 12V are only provided when the keys are in the car and turned to the accessory slot. I wanted to know if there would be any issues with this setup. Will turning the car on damage the Arduino or cause it to not function properly? Thanks.

author: richcj10
author_rank: Unknown
timestamp: August 02, 2012, 11:54:14 pm
content: use the DC input jack and you should be fine....

author: Chet T16
author_rank: Frequent Contributor
timestamp: August 02, 2012, 11:58:15 pm
content: It'll work and may well be fine but the arduino isn't designed to deal with the type of nasties can come from the cars 12v power. (high voltage transients etc)You can pick up 12v-5v DC-DC converters designed for automotive applications which would be a much better choice.

author: Unknown
author_rank: Unknown
timestamp: August 03, 2012, 12:02:53 am
content: Quote from: richcj10 on August 02, 2012, 11:54:14 pmNot such a good idea. That 12V from automotive wiring can rise as high as 14.2V when charging the battery. The op would be better with a 6 to 9v cigarette lighter supply or other suitable supply.

author: richcj10
author_rank: Unknown
timestamp: August 03, 2012, 03:54:59 am
content: The DC input jack can take more than 14 volts... (where do you get this info?)http://arduino.cc/en/Main/ArduinoBoardUnoIt might not like that, but it can do it.remember, he is not using it to drive around the world with it, just to back up with it..So, the little bit he would use, it would be no big deal...I would recommend shutting it down when not in use.. using a varistor wouldn't be a bad idea...

author: Unknown
author_rank: Unknown
timestamp: August 03, 2012, 04:20:03 am
content: Quote from: richcj10 on August 03, 2012, 03:54:59 amHave another look! See the word recommended? What does recommended mean? The OP was talking about sourcing from a vehicle fuse? What vehicle fuse is only active when reverse is engaged. He'd have two options powered permanently or ignition switched. Either will have the Arduino powered outside it's recommended operating parameter for a considerable period of time. The maximums are to cater for transients and excursions not a basis for good design. Even at usual 13.8V a raw vehicle supply will be outside the safe range for operation.

author: richcj10
author_rank: Unknown
timestamp: August 03, 2012, 04:43:30 am
content: Have you ever taken a DMM to a car and measured the voltage?It is all over the place.... usually around 11.4 for mine.Also, recommendations are there for little boys like you...It all has to do with heat dissipation.... I have had 24v input to 5v regulators before ..... You just need to know how to cool it down....Also, there are circuits only active in a car when in reverse.He could also use a novel item like a switch... but that just might be out of your league...

author: Unknown
author_rank: Unknown
timestamp: August 03, 2012, 05:10:04 am
content: Quote from: richcj10 on August 03, 2012, 04:43:30 amIt would be much safer to take you measurements while the vehicle was stationary.QuoteThe eithera) you battery is on the way outb) your voltage reg is crookc) you have excessive resistance in body earthd) you have no clue.e) some or all of the above.Quoteoh? And there was me thinking they were printed for you and other numskulls to ignore!QuoteIt has to do with safe operation. Yes I know you thought SOA was "Sons of Anarchy" but you missed the point.QuoteWhoop award yourself the Golden Teapot for services to bodge!QuoteAny designer with a clue would be more interested in how not to heat it up in the first instance?QuoteAnd how many of those are accessible at the fuse block?QuoteHe'll just as likely take a switch to you if he smokes his arduino due to your dumb advice.QuoteCareful cowboy, those air swings are robbing your brain of necessary oxygen!

author: richcj10
author_rank: Unknown
timestamp: August 03, 2012, 12:34:31 pm
content: You know you are saying a lot and not meaning much....

author: richcj10
author_rank: Unknown
timestamp: August 03, 2012, 01:57:33 pm
content: BTW:http://youtu.be/ni-4ESlbiyM

author: Monkeh
author_rank: Super Contributor
timestamp: August 03, 2012, 02:49:42 pm
content: Very impressive, you can power an Arduino off a bench power supply.Powering one off a car's electrical system is not the same.

author: richcj10
author_rank: Unknown
timestamp: August 03, 2012, 03:35:30 pm
content: How is it not the same Mr. I don't know enough to go in depth with it....You guys are over thinking this...I agree that there will be noise on the DC voltage of the car's electrical system.But, nothing out of control.@tiofilo75I suggest adding a varistor across the the DC input voltage. It will help with spikes...

author: Monkeh
author_rank: Super Contributor
timestamp: August 03, 2012, 03:44:54 pm
content: Quote from: richcj10 on August 03, 2012, 03:35:30 pmIt can be out of control. There's a reason we have automotive rated parts. Adding a simple, suitable DC-DC supply is cheap, easy, and may well save a perfectly good Arduino from going pop.

author: Short Circuit
author_rank: Frequent Contributor
timestamp: August 03, 2012, 04:02:51 pm
content: Quote from: richcj10 on August 03, 2012, 03:35:30 pmDo yourself and others a favor, and read ISO7637 before you do any more automotive recomendations.Or google for the (freely accessible) Ford EMC specification.

author: richcj10
author_rank: Unknown
timestamp: August 03, 2012, 07:31:19 pm
content: Quote from: Short Circuit on August 03, 2012, 04:02:51 pmOk, So you are going to tell me the Arduino needs RF shielding too... Because that what it says it would need...I call B-Sh*t on you. Are you going to tell me that every car charger and police scanner, etc... does this? Yea right....I would have an on/off switch on the unit to shut it off when starting the car. But then again the are circuits in the car, (like the radio) shut off when the car is starting... you could take power from there...QuoteI think that would matter on what car you had.... mine, probably yes. one of the cars controllers are mounter on the accessory fuse block...QuoteMakes a lot of sense little boy...

author: Chet T16
author_rank: Frequent Contributor
timestamp: August 03, 2012, 07:47:28 pm
content: If you're trolling, well done. If not then you seriously need to sit down, shut up and listen when people who clearly know more about these things tell you that you're wrong.

author: Short Circuit
author_rank: Frequent Contributor
timestamp: August 03, 2012, 08:36:39 pm
content: Quote from: richcj10 on August 03, 2012, 07:31:19 pmObviously, you did not read either specification.

author: Chasm
author_rank: Regular Contributor
timestamp: August 03, 2012, 10:33:18 pm
content: @tiofilo75You can connect an Arduino Uno directly, it will work - and most likely die after while.Why is that so?The power rails in a car are notoriously dirty. Significant spikes exist not only in theory but also in real life and can easily kill electronics that are not protected against them. The Ford EMC specification contains not only RF stuff but also more basic tests like transient response.Looking at pictures C1 (electrolytic, 47uF) is often a 16V type - definetly not enough.The NCP1117 has a maximum input voltage of 20V - probably not enough either.At least there is a reverse protection diode.

author: Unknown
author_rank: Unknown
timestamp: August 03, 2012, 11:43:31 pm
content: Quote from: richcj10 on August 03, 2012, 03:35:30 pmIts called good design!Quote from: richcj10 on August 03, 2012, 07:31:19 pmSure am! Every one of those is designed by someone much smarter than you. That is why they survive in a harsh environment operating from a noisy 13.8V supply.QuoteWhat a design masterstroke another switch to bother about, you should send your resume into the auto manufacturers today. In these tough economic times they could probably do with a giggle!QuoteThat is start cycle covered now how do you protect from the constant over-voltage and other transients from the cars electrics? Fit a heatsink the size of you head to the volt regulator?QuoteSo you've got a supply at the fuse block only active when reversing? Don't think so cowboy! Even if you have, you still haven't solved the other problems. Or this that over think'n? Just have a stack of spare Arduinos, right?QuoteThis is your idea of a killer blow is it cowboy?Several people have politely tried to offer you assistance, if you're too stupid to take that advice, then go smoke your own components preferably somewhere dark and soundproof!

author: GeoffS
author_rank: Unknown
timestamp: August 04, 2012, 12:16:30 am
content: Please keep your replies on topic and try not to make this a personal slanging match or the thread will be locked.

author: Unknown
author_rank: Unknown
timestamp: August 04, 2012, 12:27:32 am
content: Quote from: GeoffS on August 04, 2012, 12:16:30 amhow is pointing out dud advice off topic? Several have tried to reasonably point out the issues, and somebody just doesn't get it.The OP is asking for advice, he does not need bad/wrong/flawed advice, or his thread hijacked by some clown desperate to save face and too stupid to accept constructive criticism!

author: richcj10
author_rank: Unknown
timestamp: August 04, 2012, 01:45:30 am
content: Uncle Vernon stated is that it was not possible to supply more voltage than 12v to an Arduino. I proved him wrong. I know he doesn't like that but that is the truth.No on to this filter thing you guys must have a lust over....I build electronics for sensor systems that go into industrial applications. I know a thing or two about noisy DC voltages. I made a filter that should handle some real noise... (attached)I used such filters on 150lb robots that the entire robot runs on one singe battery with no issues with the WiFi control system.C1 is 4kv cap BTW

author: Monkeh
author_rank: Super Contributor
timestamp: August 04, 2012, 02:16:02 am
content: Quote from: richcj10 on August 04, 2012, 01:45:30 amNo, he did not. He said that 13.8V is outside the recommended operating range.

author: Unknown
author_rank: Unknown
timestamp: August 04, 2012, 02:20:13 am
content: Quote from: richcj10 on August 04, 2012, 01:45:30 amNo I stated quite correctly it was not recommended or good practice to do so! Several other posters have agreed, your advice was flawed.QuoteYou proved something! Something more to do with personality than electronics~QuoteYou can't handle the truth!QuoteFilter? Lust? You're not taking your blue pills! Are you?QuoteAnd I'm Neil Armstrong.QuoteSo it's over-voltage, over-current, and safe operating parameters that you are have a problem with, then?Quoteyou sure have a handle on noise!QuoteJust issues with over-voltage and component stress.How bout you go dangle it over some other pond and let the OP have his thread back? You've been asked politely!GeoffS can you do your stuff please and hand the thread back to the OP?

author: richcj10
author_rank: Unknown
timestamp: August 04, 2012, 02:37:44 am
content: "So it's over-voltage, over-current, and safe operating parameters that you are have a problem with, then?"WTF where did you get this? The device is still in spec.... over current? You must not know how current works.."Just issues with over-voltage and component stress."?What? Who is the troll?Also, I noticed that no-one commented on my filter. You must think it is OK... or not know enough.S that's how I know Uncle Vernon is a troll... he can't comment on facts.... only comments...He I'd known to do this on the form. Nothing new about him.....

author: Monkeh
author_rank: Super Contributor
timestamp: August 04, 2012, 02:43:55 am
content: Quote from: richcj10 on August 04, 2012, 02:37:44 amTake your attitude elsewhere, please. It's not constructive.