Err: MINTEMP
I finished assembling the prusa i3 kit today and started to preheat and calibrate the printer as described in the printing guide.
All of a sudden it stopped preheating and gave me the MINTEMP error. I have tried unplugging and replugging the heated bed and extruded thermistors but this has not fixed the error. The heated bed and extruder are NOT reporting actual values of 0. Is it possible the thermistors were shorted? What can I do to fix this?
Thank you
Re: Err: MINTEMP
Hi Julie and welcome to the forum.
A MINTEMP error is triggered if either the bed or extruder thermistor reports a temperature of less than 15 degrees C.
Therefore, if your room is cold then the error could be reported.
The 15 degree limit is set as a "failsafe" against a thermistor wire or connection being broken or a wrong connection on the RAMBo.
So, if your room temp is OK, next thing to do is to check the connections on the RAMBo. If those are OK, then you need to get out your multimeter and measure the resistance of both thermistors (at the connectors).
In this case I would suspect a poor thermistor connection at the extruder, where the thermistor leads are crimped to the cable. Check out the above and let us know please.
MAXTEMP errors are caused by a short.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Err: MINTEMP
Same problem here. Extruder thermistor reports 10°C in a 21°C room (bed thermistor is ok, reports 21°C). Checked both thermistor connections and they are fine, cable looks ok also. Measured the resistance at the connector, 285 kiloohms. Reported temperature increases if I heat the extruder with a hairdryer or so, but that's obviously not a solution. What to do?
Re: Err: MINTEMP
Hi Samuel
I believe that the thermistors should read 100 KOhm at 20 degrees C, so your resistance reading is way too high, hence the low temps.
You say you checked the connectors - did you check at the extruder end where the wires from the thermistor are connected to the cable with a crimped ferrule? It's a bit difficult to check that connection, so I think your best bet is to report the situation to support.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Err: MINTEMP
Hi Peter,
Thanks a lot for the reply, then at least I know what's wrong! The thermistor cables on my unit seem to be soldered inside heat shrink tubing near the hotend, so I haven't gotten around to measuring there yet. Will look further into it this weekend 🙂
/Samuel
Re: Err: MINTEMP
Hi Samuel
They should not be soldered as the heat transferred along the thermistor wire can melt the solder.
The hot end assembly guide is here: http://wiki.e3d-online.com/wiki/E3D-Lite6_Assembly Have a look at the thermistor section and see how it compares to yours.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Err: MINTEMP
Ah, of course, that's good to know. Seems like I've got tomorrow's tinkering cut out for me, then! Again, thanks a lot for the help.
Re: Err: MINTEMP
Just a follow up: I exposed the connection to the thermistor (which actually was soldered and not crimped) and got the same 285 KOhm reading there as well. I've emailed support now, so hopefully it will be sorted out.
/Samuel
Re: Err: MINTEMP
Hi Samuel
That's strange; should be crimped in a ferrule. Having said that, I didn't check mine; just assumed it would be assembled in accordance with the instructions.
Best way to contact support is via the "live chat" on the shop pages. That way you get an immediate response...
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Err: MINTEMP
It turns out that my MINTEMP error was caused by the extruder thermistor reading 12°-14° in my house. This is much cooler than the 22° C house. The heated bed thermistor is giving the proper reading of 22° C. Like Samuel I was able to jumpstart the thermistor with a hairdryer, but was still unable to get it to the 210° C needed to print in PLA. After multiple attempts I was only able to get the extruder to reach a reported value of around 170° C. When I finally got around to getting my multimeter earlier this weekend I tested the resistance at the connection, and got values similar to Samuel. All of these lead me to think there is a problem with the thermistor. Who is best to contact for help in getting new parts?
Thank you
Re: Err: MINTEMP
No problem, just send an email to support (you can just reply to the order confirmation email) or chat with them in the online store. Either way you'll get a quick and friendly reply 🙂 I'll probably get a replacement part sent today or so, fingers crossed!
Re: Err: MINTEMP
Hi Julie
Best way to contact support is via the "live chat" on the shop pages.
It does rather sound as though there is a thermistor problem as there are currently 3 reports of this currently open.
I will also let support know about the issue.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…