2018-04-25, 05:46 PM
(This post was last modified: 2018-04-25, 05:52 PM by mr_intensity.
Edit Reason: Updated URL to RepRap forum to point at post in question.
)
Tweaking the firmware
There isn't much thermistor wiring to check.
So, I had a long layoff from the OneUp. As mentioned in a previous post, part of the problem was that I lost my operating system...literally. For about a month, my OneUp resided in the back seat of my car. However, I found my missing OS, and was back on the war path.
There has been movement on both the hardware and software front, but first let's review a boo-boo from a previous post:
Tip: Once you have the power rails wired up to the green connector on the RAMPS board, ***NEVER*** touch those screws unless you absolutely have to.
I did not realize how badly I screwed this up until I was reviewing my previous entries. The fan cooling the RAMPS board does NOT connect to the RAMPS board green connector. Rather, it connects directly to the power rails. Thus, the following statement is false: "So, I just treated it like the cooling fan on the electronics board. I hooked it in to the screw terminals on the RAMPS board at one of the 12V rails." I should have connected it directly to the power supply rails and avoided the RAMPS connector completely.
As Denis Lemieux would say: "Two minutes, by yourself, you know and you feel shame, you know. And then you get free."
Hardware
I have not got around to adding handles to my 3D-Printer stand, but I did add a switch to the thing. I picked up a toggle switch and some electrical wire from Lowes, and had Jake (the Boy Wonder, who is in Electrician School) do the honors of wiring everything up.
It was required for me to remove the Back panel of the stand, and drill two holes in it. One hole was to run the electrical cable out, while the other was for mounting the switch. I had to countersink a large area behind the switch-mounting hole, as the wood was too thick to mount the switch.
Jake stuffed the electrical wire in the hole, then wrapped the thing in electrical tape, to form a sort of strain relief, and then backed it out so the taped up area filled the hole. Then he wired in the switch, and used some of the extra wire to run everything to the power supply.
I left the front panel of the stand unmolested, as I plan to someday mount a panel controller there.
Software
Repetier-Host (RH) gave me no information in the logs. As a matter of fact, it gave me no logs. I decided to look at an alternative that might give me better logging. In the Knoppix repositories is a package called printrun, and it's GUI console program is called pronterface. It gave me no logs, either, which made no sense. It gave me a running dialogue down the right hand side of the screen. It might have even told me that the log directory did not exist (oops! my bad). Anyway, I typo-ed the log directories in the configuration...on BOTH pronterface and RH. Anyway, once logging was fixed, the magic error message that pronterface gave to me was...
[ERROR] Error:Printer stopped due to errors. Fix the error and use M999 to restart. (Temperature is reset. Set it after restarting) Please check thermistor wiring
There isn't really much to check. The thermistor has two white wires that go from the thermistor to a plug that plugs onto the T0 posts. It isn't rocket science. It isn't even rocket engineering. It is pretty much cut and dry. Current will flow either way through the thing, so polarity is not an issue (even though I turned the plug over, and tried it the other way, anyway).
Googling the error message brought me to this discussion thread on RepRap. To quote the post:
I was surprised, upon editing Configuration.h, to find that not only was TEMP_SENSOR set to 1, but also TEMP_SENSOR_BED was set to 1. Waitaminute - I don't have a heated bed! So, my first step is to set TEMP_SENSOR_BED to 0, and see if that fixes the problem.
Nope. Same error.
Next, I set TEMP_SENSOR to 0, and was now able to move the motors. And what did I learn?
I got everything backwards.
No, really. All three axes were wired backwards. When I told Y to come forward, it went back, when I told Z to go down it went up. When I told X to go left, it went right. Do you realize how much talent it took to screw up ALL THREE axes like that? I mean, it is a simple fix (pull the wire out of the RAMPS board, flip it around the other way, and plug it back in). But one would think I would have gotten at least ONE of them right. I owe it all to clean living, and knowing something about electronics.
While the connectors are square, and really have no polarity, there is a very small arrow (triangle) raised on one side of the connector, and it points to "pin one." The RAMPS board labels pin one on all of its connectors. All I had to do was match pin one to pin one, and rely on the improving quality of Chinese industry. Their repeatability and reproducibility allowed them to screw up the wiring on all three motors in exactly the same way. In days of old, there would have been no rhyme nor reason to how they wired the motors. Now they are consistent.
As of now, the only motor that is backward (i.e. pin one still goes to pin one) is the extruder motor. Neither Pronterface nor RH would permit me to move the extruder motor with the extruder temp disabled. So, it is the one motor I did not test.
More Hardware
Running my cheap but somewhat reliable Cen-Tech meter across the thermistor read a little over 36 ohms. The longer I left the meter across the leads, the higher the reading climbed (well over 37 ohms). Running the meter across the T0 leads yielded close to 5 volts (4.97, if I remember correctly).
According to comments in Configuation.h, as well as in the post that pointed me to disabling the thermistor, the thermistor is supposed to be 100K ohms. Hm. What if I got a plug like the one on the end of the thermistor, and wired up a 100K resistor to it? I could plug this thing in, in place of the thermistor, and fake out Marlin into thinking a working thermistor is plugged in. If this idea works, I should be able to move the extruder motor, and feel if the print head is getting hot. If it passes both tests, I can shut down before the thing gets too hot. This will confirm that the problem is with the thermistor, and not RAMPS or Marlin.
What follows is a diagram of what I am talking about. Since one has to be a forum member to view pictures, and I believe many people (both members and non-members) will be looking to troubleshoot this problem, I will diagram this with "ASCII Art:"
RAMPS Thermistor Test Plug wiring diagram:
+----------+ 100K
| Plug |____/\/\/\/\___
| To | |
| T0 |---------------+
+----------+
Legaleese: WARNING - Use of the above plug could cause your extruder to overheat, resulting in potential fire, destruction of property, or even injury or death. Only use above plug sparingly, and only for testing the extruder motor/heating element in printhead. DO NOT USE FOR 3D PRINTING. You have been warned.
I might have a 100K resistor in my Arduino project pack. The adventure will be finding a plug...
There isn't much thermistor wiring to check.
So, I had a long layoff from the OneUp. As mentioned in a previous post, part of the problem was that I lost my operating system...literally. For about a month, my OneUp resided in the back seat of my car. However, I found my missing OS, and was back on the war path.
There has been movement on both the hardware and software front, but first let's review a boo-boo from a previous post:
Tip: Once you have the power rails wired up to the green connector on the RAMPS board, ***NEVER*** touch those screws unless you absolutely have to.
I did not realize how badly I screwed this up until I was reviewing my previous entries. The fan cooling the RAMPS board does NOT connect to the RAMPS board green connector. Rather, it connects directly to the power rails. Thus, the following statement is false: "So, I just treated it like the cooling fan on the electronics board. I hooked it in to the screw terminals on the RAMPS board at one of the 12V rails." I should have connected it directly to the power supply rails and avoided the RAMPS connector completely.
As Denis Lemieux would say: "Two minutes, by yourself, you know and you feel shame, you know. And then you get free."
Hardware
I have not got around to adding handles to my 3D-Printer stand, but I did add a switch to the thing. I picked up a toggle switch and some electrical wire from Lowes, and had Jake (the Boy Wonder, who is in Electrician School) do the honors of wiring everything up.
It was required for me to remove the Back panel of the stand, and drill two holes in it. One hole was to run the electrical cable out, while the other was for mounting the switch. I had to countersink a large area behind the switch-mounting hole, as the wood was too thick to mount the switch.
Jake stuffed the electrical wire in the hole, then wrapped the thing in electrical tape, to form a sort of strain relief, and then backed it out so the taped up area filled the hole. Then he wired in the switch, and used some of the extra wire to run everything to the power supply.
I left the front panel of the stand unmolested, as I plan to someday mount a panel controller there.
Software
Repetier-Host (RH) gave me no information in the logs. As a matter of fact, it gave me no logs. I decided to look at an alternative that might give me better logging. In the Knoppix repositories is a package called printrun, and it's GUI console program is called pronterface. It gave me no logs, either, which made no sense. It gave me a running dialogue down the right hand side of the screen. It might have even told me that the log directory did not exist (oops! my bad). Anyway, I typo-ed the log directories in the configuration...on BOTH pronterface and RH. Anyway, once logging was fixed, the magic error message that pronterface gave to me was...
[ERROR] Error:Printer stopped due to errors. Fix the error and use M999 to restart. (Temperature is reset. Set it after restarting) Please check thermistor wiring
There isn't really much to check. The thermistor has two white wires that go from the thermistor to a plug that plugs onto the T0 posts. It isn't rocket science. It isn't even rocket engineering. It is pretty much cut and dry. Current will flow either way through the thing, so polarity is not an issue (even though I turned the plug over, and tried it the other way, anyway).
Googling the error message brought me to this discussion thread on RepRap. To quote the post:
Quote:In Configuration.h, just change the TEMP_SENSOR_0 from 1 to 0. This will change it from being defined as a 100k thermistor to not used. Then you can run your motors without a temp. That's what I'm doing right now to test movement on my machine.
I was surprised, upon editing Configuration.h, to find that not only was TEMP_SENSOR set to 1, but also TEMP_SENSOR_BED was set to 1. Waitaminute - I don't have a heated bed! So, my first step is to set TEMP_SENSOR_BED to 0, and see if that fixes the problem.
Nope. Same error.
Next, I set TEMP_SENSOR to 0, and was now able to move the motors. And what did I learn?
I got everything backwards.
No, really. All three axes were wired backwards. When I told Y to come forward, it went back, when I told Z to go down it went up. When I told X to go left, it went right. Do you realize how much talent it took to screw up ALL THREE axes like that? I mean, it is a simple fix (pull the wire out of the RAMPS board, flip it around the other way, and plug it back in). But one would think I would have gotten at least ONE of them right. I owe it all to clean living, and knowing something about electronics.
While the connectors are square, and really have no polarity, there is a very small arrow (triangle) raised on one side of the connector, and it points to "pin one." The RAMPS board labels pin one on all of its connectors. All I had to do was match pin one to pin one, and rely on the improving quality of Chinese industry. Their repeatability and reproducibility allowed them to screw up the wiring on all three motors in exactly the same way. In days of old, there would have been no rhyme nor reason to how they wired the motors. Now they are consistent.
As of now, the only motor that is backward (i.e. pin one still goes to pin one) is the extruder motor. Neither Pronterface nor RH would permit me to move the extruder motor with the extruder temp disabled. So, it is the one motor I did not test.
More Hardware
Running my cheap but somewhat reliable Cen-Tech meter across the thermistor read a little over 36 ohms. The longer I left the meter across the leads, the higher the reading climbed (well over 37 ohms). Running the meter across the T0 leads yielded close to 5 volts (4.97, if I remember correctly).
According to comments in Configuation.h, as well as in the post that pointed me to disabling the thermistor, the thermistor is supposed to be 100K ohms. Hm. What if I got a plug like the one on the end of the thermistor, and wired up a 100K resistor to it? I could plug this thing in, in place of the thermistor, and fake out Marlin into thinking a working thermistor is plugged in. If this idea works, I should be able to move the extruder motor, and feel if the print head is getting hot. If it passes both tests, I can shut down before the thing gets too hot. This will confirm that the problem is with the thermistor, and not RAMPS or Marlin.
What follows is a diagram of what I am talking about. Since one has to be a forum member to view pictures, and I believe many people (both members and non-members) will be looking to troubleshoot this problem, I will diagram this with "ASCII Art:"
RAMPS Thermistor Test Plug wiring diagram:
+----------+ 100K
| Plug |____/\/\/\/\___
| To | |
| T0 |---------------+
+----------+
Legaleese: WARNING - Use of the above plug could cause your extruder to overheat, resulting in potential fire, destruction of property, or even injury or death. Only use above plug sparingly, and only for testing the extruder motor/heating element in printhead. DO NOT USE FOR 3D PRINTING. You have been warned.
I might have a 100K resistor in my Arduino project pack. The adventure will be finding a plug...
![[Image: avatar_23.png?dateline=1515658171]](https://fabric8r.com/community/uploads/avatars/avatar_23.png?dateline=1515658171){kind=avatar}