Been working on configuring my Duet WiFi board.
While doing so, I am setting up thermistor for my genuine E3Dv6 hotend.
In the Duet documentation source1, it reads:
The Semitec 104GT-2 thermistor supplied with the E3Dv6 hot end has a quoted B value of 4267, but the actual value over 25C to 220C is 4388. For greater accuracy, use a C parameter as well.
I dug some for more information on the E3D site, where they even have a section to setup on RepRapFirmware.There are 2 items of interest here, where the first is the B Value:
For firmware versions 1.16 and earlier, set the B parameter (beta value) to 4388. This value gives better accuracy at typical printing temperatures in the range 190 to 250C than the B value of 4267 quoted in the datasheet......... For firmware versions 1.17 and later, set the B parameter to 4725
It actually means E3D is telling us the same thing: to use 4388 as B... but only for old firmware. E3D says we should set B at 4725 when using new firmware.. does it mean Duets documentation on this is no longer valid?
For firmware versions 1.17 and later, set the B parameter to 4725 and the C parameter to 7.06e-8.
I have tried it and C705e-8 does not result in an error, but is it right, or?
Tech WriterMS Infrastructure Specialist inc. Cisco
That section of the E3D wiki is correct. I wrote it. Which Duet documentation page is out of date?
The parameter C7.06e-8 (with the decimal point, which you left out) is correct.
Duet WiFi hardware designer and firmware engineerhttp://www.escher3d.comhttps://miscsolutions.wordpress.com
I was looking at this today. I think https://duet3d.com/wiki/Connecting_thermistors is the page in question. It mentions the 4388 value but doesn't mention the 1.17 firmware variation that I can see.
Out of interest, what sort of temp difference would you expect from B4388 vs B4725 C7.06e-8? Is it significant?