Weird Printrbot+ problem

Need help troubleshooting hardware issues... talk here

Weird Printrbot+ problem

Postby Michele31415 » 2017-Aug-Mon-15-Aug

When I turned on my Printrbot+ today it started acting weird. I can connect to it OK, and move the axes around OK. But as soon as I try to turn on either the bed heat or the extruder heat it stops responding and I get a "printer disconnected" error, and I don't get any heating. And when I pulled the USB plug to cycle that, the 5 V. LED's I have illuminating the nozzle end become dim. When I pug the USB back in, they get bright again.

I'd say "power supply problem" but a voltmeter reading on the 5 v. line from the power supply shows 5.18 and that does not change no matter what else is going on (USB plugged/unplugged, etc.) Also, the 12 V. line measures 12.20 and that does not change when I turn on the heat. What could be causing this? I'm mystified.
  • 0

PB+ no. 2548 (Oct. 2012) - This is my Printrbot. There are many like it, but this one is mine.
GT-2 belts and metal pulleys, x&y; Injection molded extruder gears
40 mm. cooling fan, glass bed, LED extruder lights, pilot light
Anti-jam extruder feed tube, roller filament guide, soldered bed heater connection
User avatar
Michele31415
Honeycomb infill 25%...
 
Posts: 255
Joined: 2012-Oct-Wed-11-Oct
Location: Planet Claire
Reputation: 0

Weird Printrbot+ problem

Sponsor

Sponsor
 

Re: Weird Printrbot+ problem

Postby RetireeJay » 2017-Aug-Mon-19-Aug

Before you ask the board for heat, are you able to read the temperature indicated by the bed and hot end thermistors? It should be somewhere near room temperature (20 - 25C or thereabouts).

You said that something funny is going on with LED's that you have connected to the 5V supply. The thermistor circuits also use 5V to supply "excitation" to the thermistors, so if the 5V supply is not stable, and drops just a little bit, it could cause some funny things to happen to temperature readings. All the logic circuitry is powered from 5V, so if the voltage drops a little further it will definitely cause very erratic performance (or no performance at all).

There's a funny characteristic of the 5V circuitry on the board. It can receive 5V power coming in on the USB cable, but there's also a 5V regulator on the board that takes 12V and reduces it down to 5V The two 5V circuits are wired together (through a solder jumper on the board), so either or both can be active. So when you observe a change of brightness upon unplugging the USB cable, that would indicate a possible problem with the on-board 5V regulator. When you say that you measured the 5V supply and found it stable, where were you measuring? If you were measuring the 5V coming out of the ATX supply, that's irrelevant because the 5V ATX supply isn't connected to the board at all. You need to measure the 5V on the board itself (or perhaps the 5V you're using to power those dimming LED's, which I guess comes from the board).

Hope this helps
-RJ
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4749
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 477

Re: Weird Printrbot+ problem

Postby Michele31415 » 2017-Aug-Tue-00-Aug

Ah ha! Yes indeed I was measuring the 5 V. on the ATX cable since there was a free connector there and that was easier than flipping the printer over to access the board. But I guess that's where we're headed next. I wasn't aware of the 5 V. funniness. I didn't notice if I was getting a teperature reading at all. I'll take a look at that too tomorrow. Thanks!
  • 0

PB+ no. 2548 (Oct. 2012) - This is my Printrbot. There are many like it, but this one is mine.
GT-2 belts and metal pulleys, x&y; Injection molded extruder gears
40 mm. cooling fan, glass bed, LED extruder lights, pilot light
Anti-jam extruder feed tube, roller filament guide, soldered bed heater connection
User avatar
Michele31415
Honeycomb infill 25%...
 
Posts: 255
Joined: 2012-Oct-Wed-11-Oct
Location: Planet Claire
Reputation: 0

Re: Weird Printrbot+ problem

Postby Mooselake » 2017-Aug-Tue-11-Aug

If you have access to another power supply try swapping them. ATX supplies might have multiple 12V sources (iirc they call them "rails") and one might be bad. Unplug and take a look at the inside of the connectors, and if you happen to have some electronic contact cleaner (I use DeOxit, but it's spendy) try that, too.

Sure sounds like a power problem, either in the supply or wiring. The bed draws a fair amount of power and either the power supply isn't up to snuff, or there's a high resistance connection somewhere in the wiring that's causing a voltage drop when the current increases.

Does Planet Claire have anything to do with those American Girl dolls? Not sure we had a Claire, but Molly, Samantha, and several custom versions (plus a lot of accessories...) are still hanging around waiting for another generation of girls. Just found the oldest daughter's matching Molly dress while cleaning out the cedar closet. Perhaps her 12 week sonogram will turn into a Molly dress wearer.

Kirk
  • 0

Modified KickStarter Classic Plus 7/2012
KS Thingybot Delta Pro 10/31/16
User avatar
Mooselake
My next printer is...
 
Posts: 3494
Joined: 2011-Dec-Tue-23-Dec
Location: Moose Swamp, Upper Michigan, USA
Reputation: 170

Re: Weird Printrbot+ problem

Postby RetireeJay » 2017-Aug-Tue-13-Aug

Mooselake raises a good point about the 12V supply perhaps being the culprit. If you were measuring it at a "convenient" plug on one of the ATX cables instead of measuring it directly on the board, you may have missed the problem.

Mooselake, congratulations on joining the grandparents' club!
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4749
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 477

Re: Weird Printrbot+ problem

Postby Mooselake » 2017-Aug-Tue-15-Aug

RetireeJay wrote:Mooselake, congratulations on joining the grandparents' club!

Not quite there yet :)

Kirk
  • 0

Modified KickStarter Classic Plus 7/2012
KS Thingybot Delta Pro 10/31/16
User avatar
Mooselake
My next printer is...
 
Posts: 3494
Joined: 2011-Dec-Tue-23-Dec
Location: Moose Swamp, Upper Michigan, USA
Reputation: 170

Re: Weird Printrbot+ problem

Postby Mooselake » 2017-Aug-Tue-15-Aug

Michelle, I see you had a similar problem a year ago with smoking contacts. Sounds like you already have some of the magic contact elixir DeOxit. Did you ever get one of those 2 wire panel meters?

Kirk
  • 0

Modified KickStarter Classic Plus 7/2012
KS Thingybot Delta Pro 10/31/16
User avatar
Mooselake
My next printer is...
 
Posts: 3494
Joined: 2011-Dec-Tue-23-Dec
Location: Moose Swamp, Upper Michigan, USA
Reputation: 170

Re: Weird Printrbot+ problem

Postby Michele31415 » 2017-Sep-Fri-16-Sep

My apologies for not following up sooner. I've been preoccupied dealing with a disk head crash on my Alto.

Mooselake wrote:Michelle, I see you had a similar problem a year ago with smoking contacts. Sounds like you already have some of the magic contact elixir DeOxit. Did you ever get one of those 2 wire panel meters?

No, and I'm kicking myself that I didn't. It would have made ife much easier.
RetireeJay wrote:Mooselake raises a good point about the 12V supply perhaps being the culprit. If you were measuring it at a "convenient" plug on one of the ATX cables instead of measuring it directly on the board, you may have missed the problem

Yup, I was doing the convenient thing alright. Read on...
Mooselake wrote:If you have access to another power supply try swapping them. ATX supplies might have multiple 12V sources (iirc they call them "rails") and one might be bad. Unplug and take a look at the inside of the connectors, and if you happen to have some electronic contact cleaner (I use DeOxit, but it's spendy) try that, too.

Sure sounds like a power problem, either in the supply or wiring. The bed draws a fair amount of power and either the power supply isn't up to snuff, or there's a high resistance connection somewhere in the wiring that's causing a voltage drop when the current increases.

Does Planet Claire have anything to do with those American Girl dolls? Not sure we had a Claire, but Molly, Samantha, and several custom versions (plus a lot of accessories...) are still hanging around waiting for another generation of girls. Just found the oldest daughter's matching Molly dress while cleaning out the cedar closet. Perhaps her 12 week sonogram will turn into a Molly dress wearer.

No, this Planet Claire is a song by the B-52's: https://www.youtube.com/watch?v=47YAcpCa5dM But congrats to your daughter anyway :-)

I do have another ATX power supply but after flipping the printer on its side and measuring the +5 V from the accessory jumper (EXP2, pin 2), I found it is indeed zero. Zip, zilch, nada, the square root of nothing. If I plug in the USB, it rises to 5 V. No USB, no voltage.

So I assume that U1, the LM2841 has cooked off. The easiest thing for me to do would be to simply connect 5V from the ATX to EXP2 pin 2. Is there any reason not to do this?

What an odd design. If the board was going to be powered from a PC power supply anyway, why not just use its 5V instead of sticking an extra IC on the board to convert 12V to 5?
  • 0

PB+ no. 2548 (Oct. 2012) - This is my Printrbot. There are many like it, but this one is mine.
GT-2 belts and metal pulleys, x&y; Injection molded extruder gears
40 mm. cooling fan, glass bed, LED extruder lights, pilot light
Anti-jam extruder feed tube, roller filament guide, soldered bed heater connection
User avatar
Michele31415
Honeycomb infill 25%...
 
Posts: 255
Joined: 2012-Oct-Wed-11-Oct
Location: Planet Claire
Reputation: 0

Re: Weird Printrbot+ problem

Postby RetireeJay » 2017-Sep-Fri-19-Sep

Michele31415 wrote: If the board was going to be powered from a PC power supply anyway, why not just use its 5V instead of sticking an extra IC on the board to convert 12V to 5?

Because often the boards are powered by laptop supplies, which are 12V only. That's particularly true for the Simples or other printers without heated beds.
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4749
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 477

Re: Weird Printrbot+ problem

Postby Michele31415 » 2017-Sep-Fri-19-Sep

Ah, OK then, that makes sense. Being as this is the only 3D printer I've ever used, I didn't realize. So can I just jumper in some external 5V without danger of smoking the board?
  • 0

PB+ no. 2548 (Oct. 2012) - This is my Printrbot. There are many like it, but this one is mine.
GT-2 belts and metal pulleys, x&y; Injection molded extruder gears
40 mm. cooling fan, glass bed, LED extruder lights, pilot light
Anti-jam extruder feed tube, roller filament guide, soldered bed heater connection
User avatar
Michele31415
Honeycomb infill 25%...
 
Posts: 255
Joined: 2012-Oct-Wed-11-Oct
Location: Planet Claire
Reputation: 0

Re: Weird Printrbot+ problem

Postby RetireeJay » 2017-Sep-Fri-21-Sep

Well, I would qualify that by suggesting that having the 12V and 5V turn on and off together would probably be a good thing. But I think that's what you had in mind anyway. ;)
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4749
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 477

Re: Weird Printrbot+ problem

Postby Michele31415 » 2017-Sep-Sat-12-Sep

Well this is perplexing. I decided to connect the +5 coming from the ATX power supply to EXP2 pin 2. But first I figured I'd test it by measuring from the ATX +5 V (red wire) to ground on the Printerboard, at EXP2 pin1. And it reads -6.3 V. Yes, that's negative 6.3. I double checked the test lead polarities and they're correct.

If I measure the ATX +5 v. red wire to the ATX's own ground, it is in fact +5 V. But measuring from ATX ground to EXP2 pin 1 (which should also be ground) reads -11.1 v! (Meter ground lead connected to pin 1, meter red lead connects to ATX ground).

Looking at the schematic, I don't really see how that could be. Any ideas?
  • 0

PB+ no. 2548 (Oct. 2012) - This is my Printrbot. There are many like it, but this one is mine.
GT-2 belts and metal pulleys, x&y; Injection molded extruder gears
40 mm. cooling fan, glass bed, LED extruder lights, pilot light
Anti-jam extruder feed tube, roller filament guide, soldered bed heater connection
User avatar
Michele31415
Honeycomb infill 25%...
 
Posts: 255
Joined: 2012-Oct-Wed-11-Oct
Location: Planet Claire
Reputation: 0

Re: Weird Printrbot+ problem

Postby RetireeJay » 2017-Sep-Sat-13-Sep

Maybe the ATX +5V supply and the 12V supply are independent of each other (at the supply) - i.e. the ground of one is not connected to the ground of the other? That seems unlikely (the grounds on my ATX are definitely not independent) but it would explain the strange offsets you are seeing.

If, for some reason, the grounds really are floating at the supply, it surely is possible and permissible to connect them to each other somewhere else. But I'd proceed cautiously (like do this experimentally without connecting to the Printrboard before finalizing the wiring)
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4749
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 477

Re: Weird Printrbot+ problem

Postby Michele31415 » 2017-Sep-Tue-15-Sep

Mooselake wrote:Michelle, I see you had a similar problem a year ago with smoking contacts.


Um, yup. The Moose takes the prize. I reached back behind the printer stand and dredged up this:
clipboard.jpg

So I had two burned out ground lines in the 12V supply. I guess the remaining two weren't up to the task. The fact that 5V was present with the USB connected but not without it was a red herring that led me down the wrong path. You'd think there should have been enough 12V left to at least power the board if not the heaters. In my defense, I was thinking I'd solved my bruned contact problems last time. Bzzt. Wrong. This time it was the remaining square 4-pin connector that went.

I finally decided this was God's way of telling me to simply get rid of the junky power supply that came with the printer. Rather than hard-wiring those wires, I went down to the friendly local computer shoppe and picked up a 450W CoolerMaster ATX supply. PLugged it in, turned it on, hey presto problem solved.

So big thanks to you and Jay for helping me figure this out. Jay, I hope you didn't get any damage from Irma.
  • 0

You do not have the required permissions to view the files attached to this post.
PB+ no. 2548 (Oct. 2012) - This is my Printrbot. There are many like it, but this one is mine.
GT-2 belts and metal pulleys, x&y; Injection molded extruder gears
40 mm. cooling fan, glass bed, LED extruder lights, pilot light
Anti-jam extruder feed tube, roller filament guide, soldered bed heater connection
User avatar
Michele31415
Honeycomb infill 25%...
 
Posts: 255
Joined: 2012-Oct-Wed-11-Oct
Location: Planet Claire
Reputation: 0

Re: Weird Printrbot+ problem

Postby RetireeJay » 2017-Sep-Tue-15-Sep

Glad you got the problem solved! :D

Michele31415 wrote:Jay, I hope you didn't get any damage from Irma.


Thanks. Monday night here was very windy, with steady but not heavy rain, and our power went out several times for a few seconds at a time. But there was no significant damage; just leaves and twigs all over the place. My wife has several relatives in Florida, and they are all OK too. In the early phase, the forecasters were saying Jacksonville would get hit, so one relative there evacuated days ahead of the storm. Then they were saying Tampa area (and not Jacksonville) would get hit, so a Tampa-area relative there evacuated to central FL. But in the end, Tampa did not get hit as bad as they were expecting while central FL and Jacksonville did get hit pretty bad. So even forecasts made just a few hours beforehand turned out to be inaccurate! Never trust a hurricane. :(
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4749
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 477


Return to Troubleshooting talk

Who is online

Users browsing this forum: No registered users and 1 guest