zaippy

I have something to add up with. I did another test by combining 134a and 134b together, where I set 134a Address 0 channel 3 connected and 134b Address 1 channel 0 connected. Reboot and check EEMPROMS. Then I run the example code “single value read”. I’m asked to select the Address. No matter which Address I choose, I only get reads from Channel 3 (correct temp reads around 20), others left “Open”. Then I switch only their Address, I still only get reads from Channel 3. But this time is Channel 3 “Common Mode”.

Thanks for reply. Well, the wires are fine. They’re just extension of thermocouples. But I still unplug them all as you suggest. I actually have two 134 boards(I shall name them 134a and 134b). I set them both as jumper A0, which means Address 1. Board 118 on Address 0 as always. When I use 134a or 134b alone, they both worked fine. Once I combined 118 and 134a, 134a would come up with around -240 C on all channels even I unplugged all the wires and thermocouples. For 118 and 134b, 134b would show “Open” on all the channels though I connect one thermocouple on Channel 0 (and it works when 134b works alone). P.s. I reboot my Pi and check EEPROMS every time. That’s really weird. If the problem is with my Pi, two 134 boards should have the same “Symptom”.

Moin Fausto, thanks for your reply. I’m using Pi4 Model B, and OS is Raspberry Pi aarch64 Debian GNU/ Linux 11 (bullseye). Here are my settings: 118 no jumper and 134 one jumper on A0 bottom to top: Pi 118 134 Now the 118 works great, have readings on all channels with 1.748V, and 5V on Channel 0 where I test it with a 5V power bank supplier. But for 134 things not ok. It has readings on all channels with -243~-244 C. I only connect channel 0-2 with sensors and channel 3 suppose be “Open”.

Moin, I’m trying to follow the Documentation 2.2 to stack my MCC 118 and MCC 134 together. Now I had such a problem. When I separately use them, they both worked well. So the hardware is ok. When I try to stack them together, MCC 134 with address 0 still worked, but MCC 118 with address 1 would be “Addr 1: incorrect response”. I’ve check the EEPROMS every time. i don’t know how to let MCC 118 work together with 134.