Major problem, need help asap

Re: Major problem, need help asap

Maxx Mayhem — Thu, 09 May 2013 09:57:26 -0400

It sounds like you are either getting an external power surge (need a surge protector) or you are encountering a spike in internal resistance for some reason(jammed extruder, faulty or overheating electronic component, mechanical jam.) It is also possible that you have an over voltage on your input which would eventually overheat your vreg over time causing it to fail.

Re: Major problem, need help asap

ShadowRam — Wed, 08 May 2013 10:07:11 -0400

Use your multi-meter diode test function.

It should only beep(conduct) in one direction.

You'll have to test the diode when it is not installed on the board.

More Diode Testing information here

Re: Major problem, need help asap

matrix4721 — Wed, 08 May 2013 09:52:22 -0400

Is there a way i can test the diodes? what is diode 2 responsible for? and if its faulty could it cause further damage? i have several new diodes from past projects but is it worth replacing any as the ones that are already attached to the ramps board are new?

Re: Major problem, need help asap

ShadowRam — Wed, 08 May 2013 09:45:03 -0400

matrix4721 Wrote:
-------------------------------------------------------
> Hi all, ive tried what shadowram said about
> removing the diode on the ramps board and powering
> it from both the USB and the 12v input and its
> working again, aside from needing the USB being
> connected all the time are there any downsides to
> doing it this way? btw im using the gadgets3d lcd
> ramp w/sd card, i would consider buying another
> arduino board however seeing how its blown the
> voltage regulator twice on 2 seperate boards im
> abit unsure about it

No there are no downsides other than the need to stay connected to a computer.

Anyone that is using a 24V system absolutely has to remove that diode anyway. (I'm only using 12V but my diode isn't installed, as I'm planning on it staying connected to a computer anyway)

Like I said before, if you really want to run the system off an SD Card without that diode, you just need to supply a clean regulated 5V source down the USB cable.

EDIT: Actually I just thought of something. Have you measured your 12V source? It is 12V and not higher correct?

Re: Major problem, need help asap

matrix4721 — Wed, 08 May 2013 09:30:52 -0400

Hi all, ive tried what shadowram said about removing the diode on the ramps board and powering it from both the USB and the 12v input and its working again, aside from needing the USB being connected all the time are there any downsides to doing it this way? btw im using the gadgets3d lcd ramp w/sd card, i would consider buying another arduino board however seeing how its blown the voltage regulator twice on 2 seperate boards im abit unsure about it

Re: Major problem, need help asap

VDX — Wed, 08 May 2013 08:56:55 -0400

... could be there's somewhere a near short between +5V and +12V or to GND (maybe a wrecked capacitor?) - so the 'weakest' of the voltage-regulators will blow first :S

Re: Major problem, need help asap

matrix4721 — Wed, 08 May 2013 08:50:02 -0400

Hi all, thanks for your replies, i have good news and bad news, good news is that i was able to borrow a mega 2560 board from a friend of mine and everything worked, the display worked fine under both USB and 12v, it worked for about 30 minutes and then popped with aload of smoke, i disconnected the power and removed the arduino board to discover it had blown a small hole in the larger voltage regulator (the one beside the AC jack), so no back to where we were before, USB power works but as soon as i connect the 12v the display fills with blocks, ive measured the 12v power supply and its kicking out 11.52v, any ideas whats caused it? (please note the only things that were connected were the arduino/ramps 1.4/12v psu and a fan, no driver boards or endstops or steppers)

Re: Major problem, need help asap

ShadowRam — Tue, 07 May 2013 10:00:34 -0400

rhmorrison Wrote:
-------------------------------------------------------
> > Right, but he doesn't have much a choice, unless
> he wants to buy a new Mega 2560
>
>
> Why that?
> Worst case all he needs is to add an LM7805 to his
> circuit to derive the 5V from his 12V supply.

No.

If he does that, he could ruin the board even more. You don't want to backfeed 5V into the Arduino.

For him to hook a 5V into the VCC connection, he would have to find and cut a few parts of the circuit.

He's already said he's new to electronics, and I don't think he wants to go through that process.

Re: Major problem, need help asap

rhmorrison — Tue, 07 May 2013 09:46:29 -0400

Quote
ShadowRam
Right, but he doesn't have much a choice, unless he wants to buy a new Mega 2560

Why that?
Worst case all he needs is to add an LM7805 to his circuit to derive the 5V from his 12V supply.

Re: Major problem, need help asap

ShadowRam — Tue, 07 May 2013 09:34:42 -0400

rhmorrison Wrote:
-------------------------------------------------------
> If you ever want to run stand alone using LCD and
> SD card then I don't recommend running off the USB
> 5V.

Right, but he doesn't have much a choice, unless he wants to buy a new Mega 2560

And even if he did want to use these later without buying a new Arduino, he could just hack an old USB cord in half, and wire a 5V Regulator to the USB Power inputs, and power the Arduino through the USB.

The arduino wouldn't know any better if the 5VDC was coming from an actual computer or not.

Re: Major problem, need help asap

rhmorrison — Tue, 07 May 2013 09:29:52 -0400

If you ever want to run stand alone using LCD and SD card then I don't recommend running off the USB 5V.

Re: Major problem, need help asap

ShadowRam — Tue, 07 May 2013 09:24:36 -0400

Ok,

So you measured 4.88V. That's good. No need to go buy anything yet.

EDIT: Sorry, I though you measured this at your EndStop connection points, but re-reading it looks like you read this off a 5V regulator not attached to anything. Check the 2nd picture attached and measure VCC while the USB is plugged in.

If you are getting 5V at VCC, then across the board is getting 5V.

Most likely it's getting this regulated voltage from the USB.

But when you connect the 12VDC, the board dies.

Do you have Diode 1 installed on the RAMPS?
See attached for location

If so, remove it.
This will prevent the 12V from going to the Arduino.
This means that you will not be able to run the printer without it hooked up to the USB.
(Which isn't a problem unless you have an SD Card setup anyway)

The Arduino and everything else will rely on the USB 5V instead of the Arduino trying to convert 12V to 5V

Re: Major problem, need help asap

Maxx Mayhem — Mon, 06 May 2013 22:30:02 -0400

I would probably not connect/disconnect any shields under power. And sheck is right, you really need a minimum of 6 to 7 volts input. If you are getting less than 5 volts you may or may not get output, however since your USB seems otherwise to be working, I don't think that is the problem. Also realize that when you have a power supply (which I am assuming you have tested with a volt meter) hooked up, the power from your USB is redundant. USB will run your arduino all day, but when you start adding loads, I think you are are good for maybe <800mA? So in practice, you need a working throughput from a full power supply to print with. I believe the voltage regulator is a key piece on the arduino. Side story about voltage regulators- In my younger days I once worked a concert with George Thoroughgood and the Destroyers. (Bad to the bone) As the techs were setting up, a voltage regulator failed in a power supply connected to the stage lighting. Within seconds, an $80,000.00 lighting console was up in flames. Pretty impressive for a 2 dollar part, eh? So they are important.B)-

Re: Major problem, need help asap

sheck626 — Mon, 06 May 2013 21:18:10 -0400

Have you tried disconnecting one of the 12v pairs and seeing if that works?

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 20:31:45 -0400

yeah its defo a weird fault, ive tried connecting it in multiple ways, usb first, then 12v, 12v, then usb, results have been the same

Re: Major problem, need help asap

sheck626 — Mon, 06 May 2013 19:34:24 -0400

Assuming it's a linear voltage regulator, you will need more than 5v on the input to get any output. The +5v on the Arduino is derived from the USB connector which is already regulated, so I don't see why another regulator would be necessary to deliver +5v to the RAMPS board. I also don't see why it would work just fine with the +12v switched off, but fail when it's switched on. Have you tried switching the +12v on first, and then plugging in the Arduino? I've noticed that the Arduino is very sensitive to EM noise and the turn-on transient of my PSU is sometimes enough to mess it up. The 5v circuit is working fine or else your display wouldn't work at all.

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 19:33:32 -0400

where would i attach the 5v to the ramps board? the main power inputs are 12v?

Re: Major problem, need help asap

Sublime — Mon, 06 May 2013 19:26:44 -0400

You should just grab yourself a 5v wall transformer like an old phone charger and try supplying 5v to the 5v input of the RAMPS board to see if you have burnt out anything else and confirm it works before waiting to have parts delivered that may not fix the issue and waiting as long as it would take to get an entire new set of electronics.

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 19:22:07 -0400

Right okay, i'll order a voltage regulator and attempt to repair the board, so am i right in assuming that when the regulator is working correctly (powered by the usb) it should have multimeter readings on both the input and output pins?

Re: Major problem, need help asap

Maxx Mayhem — Mon, 06 May 2013 19:05:23 -0400

That sounds like the problem. If you check the wiki on the arduino,[arduino.cc] it has the diagram. You want to power the board thru usb or the psu input, and not the power pins on the board for testing, as the power pins bypass the voltage regulator and doing so could further cause damage if out of range. Also, you really want at least around 7 volts coming in for things to work properly. (12 max)

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 16:56:36 -0400

okay forgive me if this sounds stupid, im trying to teach myself electronics as we go, right, if im correct, looking down at the voltage regulator you see 3 pins, the left pin is input, middle pin is ground, right pin is output, if i measure the input and ground pins i get 4.88v, if i measure the ground and output i get 0v

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 16:49:49 -0400

Just checking it now, if i use the earth on the left pin and and check the other test probe on the middle/right/top pins i get 4.88v, if i try any other combo i get 0v, does that sound right?

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 16:41:15 -0400

How would i go about finding that out? im guessing id using a multimeter to check the pins of the voltage regulator?

Re: Major problem, need help asap

ShadowRam — Mon, 06 May 2013 16:33:57 -0400

Yeah it should do the trick.

You aren't pulling a lot of current on these 5V lines, it's mostly just for signalling.

But you should find the pins on the Arduino first while it is plugged into the USB, and make sure my theory that those 5V Supply pins aren't working is correct.

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 15:33:04 -0400

That might not be a bad idea, ive seen ''2 x SMD SMT LM1117 AMS1117 Voltage Regulator 5V 800mA'', would they do the trick?

Re: Major problem, need help asap

Maxx Mayhem — Mon, 06 May 2013 15:18:11 -0400

I just got done buying a bunch of electronic parts on ebay from Tayda2009 who does bulk individual parts dirt cheap. Many are 99 cents free ship. I mention this because you could probably get a new voltage regulator for a buck and fix your arduino. If you do this, cut the leads close to the component on your old regulator before attempting to desolder it. It is a whole lot easier that way and you wont be as likely to damage the lands on your circuit board. I like 25 watts for such work.

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 14:14:29 -0400

Hey shadowram, thanks for your help, so your saying that by accidently connecting the endstops to the bottom set of pins (+5v rail) that it actually damaged the arduino board and not the ramps board? if thats the case then im lucky you spotted it cos i nearly ordered another ramps board, its a shame cos the arduino still works and accepts code but obviously the part that connects to the ramps board is shorted if im understanding it correctly

Re: Major problem, need help asap

ShadowRam — Mon, 06 May 2013 13:43:56 -0400

If you connected the wrong two rows on the end stops you shorted it out.

Your mechanical switches shorted the 5V+ and Ground.

I'll have to check the schematic to see what could have burnt as a result of doing this.

EDIT: Yup, looks like you blew VCC which looks like its a regulated +5VDC source from the Arduino itself.

So you have 2 choices.

Replace the Arduino, or hack in your own 5V regulator.

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 13:07:45 -0400

BTW on the picture of the ramps board you'll see where the endstops connect to has 3 rows, i think the endstops connect to the top 2 rows and i think i connected them to the bottom 2 rows, as the error occured as the head touched the endstop im guessing its shorted something, but not knowing what the bottom row of pins were for im not sure

Re: Major problem, need help asap

matrix4721 — Mon, 06 May 2013 12:21:31 -0400

Hi, thanks for the reply, ive attached afew photos of the boards and how it responds when the 12v is attached and when its not, i'll broken out the multimeter but so far everything seems to be okay on the ramps board, if anyone spots something ive missed or have any suggestions on what i can check feel free to shout out