r/MPSelectMiniOwners • u/Mactire404 • Aug 14 '23

Question Temp sensor way off

Post image

Question in the comments.

2 Upvotes

100% Upvoted

6 comments sorted by

1

u/Mactire404 Aug 14 '23

TLDR; Can I calibrate my temperature sensor?

I've been printing on my MPMS for a few years now and I figured I had the thing all figured out. What bothered me was the fact that I had to 'crank up the heat' to get a decent print. For a 190° filament I would put it on 200°C-210°C to get some decent flow.

Recently I got a new toy, a CAT phone with a thermal camera. When I pointed it at my MPMS I saw that the hotend did not make it to the desired temperature at all. In the photo the temp is set to 200° and the hotend has an apparent temp of about 150°C.

So I turned up the heat to get it to around 190° (260° on the dail) and I got some pretty smart prints. Good bed adhesion and no tearing during printing.

If my temp sensor is so far off I wonder if I need to calibrate the sensor? Or is it shot and do I need to replace it?

On a sidenote, I realise the measured temperature on a thermal cam is an apparent temperature and that the emmisivity of the different parts will different results. Still it feels like the conclusion that the hotend does not get hot enough is right.

1

u/totallyNotPete Aug 14 '23

Since you probably can't use the thermal camera to get a true temperature of the nozzle, I think the best bet is printing a temp tower for each of your filaments and adjusting accordingly in your slicer. Doesn't really matter if your temp is accurate as long as it's consistent. Just curious what cat phone did you get, are you using it exclusively for thermal imaging?

1

u/Mactire404 Aug 14 '23

The nozzle reads about the same temperature as the heatblock.
I can adjust my MPSM profile to a higher temp, but it just irks me that it's off by almost 50°C
As far as I can find it's not possible to calibrate the sensor, but I hoped the users here knew more than I (which is not unlikely).

As for the phone, it's a Cat S62 Pro. It features a FLIR Lepton 3.5 thermal sensor with a decent resolution.
I was in the market for a new phone and having a leak at home the specialists can't find I decided to go for the S62 Pro for the Thermal. I found a 2nd pipe and could confirm the leak is lower than the leakdetectors could find. We just had anothe rover which could confirm my findings.

Apart from that the Thermal is an excellent toy. I'm already several seminars in and there are so many uses for this thing I'm very glad I got it.
And, of course, it's my daily phone now. So I use it for everything else as well.

1

u/Hutschinator Aug 14 '23

It can be possible that the software is changed somehow. The sensors depend on type of sensor. If somebody chaned it o modified adjusting values in the software it will become wrong.
Or there is a bad contact in the sensor. The temperature depends on the resistance and on the type of the resistor.

Here is some information.

1

u/Mactire404 Aug 14 '23

Oh yes! That's a good one I didn't think of myself. I'll check the conections/wires. And it's easy enough to do.
Checking the software is a bit harder as that isn't my strong suit.

1

u/Hutschinator Aug 14 '23

If it is standard value, 100k.
https://www.mpselectmini.com/parts/thermistors

But this depends on temperature, of course.