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RoryHickford

Ultimaker maxtemp/mintemp keeps triggering with brand new gear!

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hello ultimaker forums :)

i recently bought a second hand ultimaker original to be my second 3D printer (self built prusa i3). It was in a bit of state when I got it, but I was aware of its faults and I thought it could be fixed with my okay knowledge of 3D printing.

I have replaced pretty much every electrical component on it and I am still getting mintemp and maxtemp errors, I have researched people with similar problems and I have seen that they made sure everything is connected that kind of thing. My printer will accurately measure temperature when connected with USB and no mains power (temp goes up when I hold heater block) main power cable is new and just yesterday I bought a brand new shield board so I could discount connection problems from thermocouple board to main board.

I also spent some time wiping my arduino (which is not new) and re-uploading marlin firmwares to see if that could help, but to no avail. it will heat for maybe a couple of seconds before it goes to 384 degrees, then crashes to 0 causing maxtemp in the process.

I have not replaced the power supply or the arduino, could those be the problem? I'm not sure if my PSU is ultimaker official either, but it does say it outputs 19v at 6.32A, the correct amount.

I just want to start printing, everything is ready to go :D

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Your main problem is likely the temp sensor, not the heater. It can't possibly get to 384.

There should be a little conversion board on the head of the printer. It should have 3 wires going back to the printer. One is ground, one is 5V and the other is temperature. It should be outputting 0V for 0C and 5V for 500C and so on. So if at room temp it should output around 200mv. Check that signal - if it's good but arduino reads 384 then indeed arduino is probably bad. Much more likely there is a loose wire somewehre in there.

Also be aware that the fan can cause interference especially if not at 0% or 100%. Keep the fan wires at least 2 cm away from thermocouple wires. There are minor edits to that board (ad597? something like that) that drastically reduce the sensitivity to interference from the fan but first make sure your problem is the fan (probably not - probably loose wire somewhere).

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Your main problem is likely the temp sensor, not the heater.  It can't possibly get to 384.

There should be a little conversion board on the head of the printer.  It should have 3 wires going back to the printer.  One is ground, one is 5V and the other is temperature.  It should be outputting 0V for 0C and 5V for 500C and so on.  So if at room temp it should output around 200mv.  Check that signal - if it's good but arduino reads 384 then indeed arduino is probably bad.  Much more likely there is a loose wire somewehre in there.

Also be aware that the fan can cause interference especially if not at 0% or 100%.  Keep the fan wires at least 2 cm away from thermocouple wires.  There are minor edits to that board (ad597?  something like that) that drastically reduce the sensitivity to interference from the fan but first make sure your problem is the fan (probably not - probably loose wire somewhere).

 

Thank you for the fast reply :)

The temp sensor has never been used before, I don't see why it would be bad? I'll have to buy a multimeter to check voltages and whatnot, I can try that on Monday :)

I don't think I have a loose connection, I get Mintemp when things are not connected on power up. Maxtemp rears its head after a few seconds when things are connected.

I currently do not have the fan connected because I heard it can cause interference. Will that cause maxtemp?

On Monday I'm thinking of going to Lancashire so 3DGBIRE can take a look at it, I don't know what else to do.

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Do you know anything about electronics? Do you have a multimeter? Are you sure you replaced the temp sensor with the right one? You want a thermocouple - not a thermistor. This is UMO, right? With the green electronics board underneath - not the newer white electronics board (which doesn't use thermocouple but instead uses PT100 part).

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Do you know anything about electronics?  Do you have a multimeter?  Are you sure you replaced the temp sensor with the right one?  You want a thermocouple - not a thermistor.  This is UMO, right?  With the green electronics board underneath - not the newer white electronics board (which doesn't use thermocouple but instead uses PT100 part).

I know a few things about electronics and I do know how to use a multimeter, I just don't own one. Yes I did, for the ultimaker original.

Yes the ultimaker original.

I got to the bottom of the problem, I removed all of the stepper motor drivers and now there is no elephants noise on startup and I can get things to heat up and down with no maxtemp or Mintemp errors.

The previous owner must have adjusted them for some reason and did it badly because I couldn't remember which order they went back in and one did magic smoke. When I get four new ones is it wise to not do any trimpot adjustments? My prusa i3 doesn't seem to care how I adjust them.

On the bright side it wasn't my wiring, and my ultimaker is working, I just need four new stepper drivers. I suspected that a couple were bust anyway because I couldn't get the extruder motor going in pronterface.

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The extruder won't turn unless you either get the nozzle above 170C or you enable "cold extrusions" (some gcode - google it).

Fortunately those "pololu" chips are very inexpensive.  They are easily destroyed if you mess with the trim pots.  You just want to turn them the tiniest amount at a time.

 

They were not cheap really £60 for 4. I bought some A4988 drivers from eBay for £10 for my I3, maybe I should have gone down that route.

On the bright side I printed something, not recognisable though, extruder is still motionless.

swapped motor sockets E motor turned fine, so it's not the motor. The driver appears to not work in any socket, so maybe it got short circuited somehow on first start-up, that was the only one I didn't adjust. When it didn't move I did adjust pot then but still nothing, and my hotend was at 210 degrees.

Tech support is talking to his manager, possibly thinks it's a bad board, but maybe I'm just not careful enough putting them in?

I however didn't try using a another driver in the E socket, I'll try that tomorrow to see if that's the problem.

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Don't let the hot end stay at 210C for an hour as this will cook PLA into a clog.  180C is safer but even easier to just do a M302 which allows cold extrusions.

Usually if the driver is a little weak or strong in current the servo still moves or vibrates or makes noise.

 

I'll try not to do that then :) I had another bit of bad luck as well last night, I didn't get ber dunk when I wanted to connect my printer, and now I can't connect for some reason. It's quite disheartening, I feel like I'm being punished for trying to get a good eBay deal :(

OK I think the socket and the driver may have somehow been toasted? Used one of my good drivers in the E socket and nothing. Is there a way to try E2 socket?

All of the drivers are tned to lowest possible setting as well, otherwise maxtemp occurs.

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maxtemp should not be related to drivers. They are completely different things. If you are getting maxtemp you might want to concentrate on that first - that means your wire is loose or something similar.

The current settings are very delicate and some versions of the pololu are clockwise and some are counterclockwise. Really you should measure the voltage at vref when you mess with those things. I've never had to adjust them.

You can mess with pins.h and make extruder0 signals go out extruder1 easy enough. If you have experience building marlin.

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maxtemp should not be related to drivers.  They are completely different things.  If you are getting maxtemp you might want to concentrate on that first - that means your wire is loose or something similar.

The current settings are very delicate and some versions of the pololu are clockwise and some are counterclockwise.  Really you should measure the voltage at vref when you mess with those things.  I've never had to adjust them.

You can mess with pins.h and make extruder0 signals go out extruder1 easy enough.  If you have experience building marlin.

 

I only get maxtemp with 4 drivers installed, otherwise temperature measurement seems pretty reliable heating up.

I changed my PSU today, the one that came with it was a Liteon PSU, tech guy said they have never shipped that brand so I got a new one from ultimaker. I didn't change anything. The drivers are tuned clockwise (ultimaker wiki) to the endstop which is no current, but I'm getting current, which I'm very confused about :( again I don't think I have a connection error, its fine without the drivers installed, maxtemp does not occur.

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