I'm liking the possibilities of an RTD circuit using the Phidgets 1046. 24-bit DAC and the option of building a circuit with optimal RTD current/voltage range and analog filtering at the bridge/DAC. It would likely result with the best noise immunity and smoothest RoR curve possible for a reasonable cost.

More reading material:
https://www.phidgets.com/?tier=3&catid= ... rodid=1027
https://www.phidgets.com/docs/Load_Cell_Primer

After more testing, my Phidgets 1048 TC looks like it is doing flakey things (shown on post above). I may consider going with the 1046 in the near future. Costs are getting up there though since I would also need to replace three TC with RTDs probes.

I purchased a custom 4-wire RTD from TC Direct. It wasn't cheap. And I only need one. I'm OK with TCs for ET and exhaust temp.

I bought a VINT Hub, 4 x TC Phidget, and a TMP1200 RTD Phidget, basically for the cost of a 1048.



This will allow me to use the RTD for my BT and hook up 4 additional TCs if I want.

If all this works, great. If not, I'll try something else.

Al, I like that option as well. BT RoR is really my only care about with being very smooth, responsive and lacking any time lag.
I could use my 1048 TC for ET & MET even though it seems to have an issue.

Almico wrote:I purchased a custom 4-wire RTD from TC Direct. It wasn't cheap.

What RTD probe did you go with? TC Direct has a huge selection. I am amazed how many RTD's have a max temp of 540F. I think I would want a probe that comfortably handles much more than that, even for BT which really shouldn't reach these temps. They do have RTDs with max temps of 1100F.

I like the looks of this probe:
https://www.omega.com/pptst/PRTF11-E-SB.html
500C rated, 3mm dia, 4-wire custom and probably pay something like $70 ea. I'd probably go with the Phidgets 1046 for $90 and make a board with precision resistors.

I ordered this one: https://www.tcdirect.com/deptprod.asp?d ... ch=314-648, but with 4-wire instead of 3.

I don't think you can use an RTD and the 1048. The RTD requires a TMP1200 through a VINT Hub connection to the computer. I don't think you can have two USB inputs with Artisan.

Thanks Al! That is a 1/8" RTD. It might be slow, but maybe fast enough.

Almico wrote:I don't think you can use an RTD and the 1048. The RTD requires a TMP1200 through a VINT Hub connection to the computer. I don't think you can have two USB inputs with Artisan.

I'm using two USB inputs to Artisan now. I'm playing with a 1045 IR sensor on one USB and 1048 on another. Works fine. But in the future, I would use the 1048 for ET and MET thermocouples and a RTD BT probe would need either a TMP1200 and VINT hub or a 1046 with a bridge circuit. Connect both the 1048 and 1046 to Artisan.

How about this one.. Looks really interesting, starts at 1/8" for durability but last 2" is 0.080" for fast response

https://www.tcdirect.com/deptprod.asp?deptid=230/27

0.125">0.080" dia x 6" long

540* max temp and I'd be concerned about that small tip.

And too responsive is not our friend here. Ideally I'd want a probe that reacts quickly, but dampens the reading. In other words a probe that will respond in a split second, but not overreact temperature-wise.

Things are moving in a good direction. Good news added on Yoctopuce modules. They released a new firmware for the YoctoTC module that dramatically reduces the noise (on the same hardware). I updated the article with the new results.

I just noticed a new firmware for TMP1101 - v107 which lists these improvements "Implemented 50/60Hz notch filter, fixed crash when seeing temperatures near maximum range". It says it was released in February, but I wasn't able to update to it until this week. Saw same mismatch with other devices too. This could improve reading on systems with lower quality power sources.

I'm trying to install my new RTD set up and having issues.











And when I turn it on I get nothing.