(Idea/Question) Pt100 sensor on UMO

[ataraxis 51]

Hi!

I am printing at around 215-220° (0.1mm/50mm/s).

I think this is the perfect temperature on my machine but i am a bit confused since normally 210°C should be enough for PLA. Therefore I did some resarch about the thermocouple and the installed sensor.

It is an K-type thermocouple and an AD597.

According to the Datasheet and Wikipedia I found the following error ranges:

AD597 (without calibration):

maximum error at ambient temp. of 60°C: +-4°C

stability: 0.05°C/°C

That means that you have a maximum error of 30*(+-0,05°C) + (+-4°C) = +-5,5°C at 30°C

if I am right.

Thermocouple type k:

class 1 at 210°C: max{0,004  * |t| = 0.84, 1.5°C} = 1,5°

class 2 at 210°C: max{0,0075 * |t| = 1.575, 2.5°C} = 2.5°C

Let's say it is an class 1 thermocouple, then we have a maximum error of +-7°C, right?

Maybe I am missing some details (like a calibration or something)?!

But if I am right, than it is quite a lot and maybe that's one of the reasons why Ultimaker changed to Pt100 sensors...

Is there maybe already a solution for Pt100 sensors at the UMO, or is there any other reason why this will not work?

Edited September 10, 2015 by Guest

[neotko 1,417]

I would drop an email to e3d about their little amplifier for pt100. I think it might/could work?

http://e3d-online.com/Electrical/Electronics-Boards/PT100-Amplifier-Board

Drop them an email, they answer really fast and they are quite friendly.

[ataraxis 51]

Looks good, Thanks! Maybe I should change the whole hotend some day... ;D

Edited September 10, 2015 by Guest

[neotko 1,417]

You could buy a umo 2.1.1 chinese version (99€) and reuse almost everything (except you would need the pt100). Even the heater works. But this kind of upgrade would work better if you have the umo bed upgrade kit because the power supply it's the same of umo+/um2. Ofc the original board from ultimaker cost 250€+ and it's much more reliable. I got an umo (not plus) box and to adapt it to the 2.1.1 board it's just as easy as making a few holes and cutting a bit the wood frame (not cute but works). If anyone goes this route on chinese board check that they put the power button and that they have the give you the safety pins. Mine didn't and it was a mess (also the connectors for pt100 and fan/led where upside down...). But they are cheapo

Edited September 10, 2015 by Guest

[neotko 1,417]

@ataraxis I was looking for other stuff and I saw this, I don't know much about this stuff but seems like it might work (the e3d little amplifier)

http://wiki.e3d-online.com/wiki/E3D_PT100_Amplifier_Documentation