Beware of a fake MAX31855 K Type Thermocouple Sensor Module

Beware of a fake MAX31855 K Type Thermocouple Sensor Module

M31855K
1424A2
+780AB

Got one module from aliexpress.

Store name - Super seller For Arduino&3D

-200 to 1350c MAX31855 Module K Type Thermocouple Thermocouple temp Sensor new

It was not working, and it was my first experience with termocouple sensors. I tought that I have probably destroyed the module - maybe with some static electricity.

Then I have ordered two others from ebay.

Store is called alimodule

MAX31855K Thermocouple Sensor Module Temperature Detection Development Module AM

But they was not working too!

Used library: https://github.com/enjoyneering/MAX31855

returns:

Chip ID: 31855
Cold Junction: 128.00
Thermocouple: 0.00

The same story for all three modules with different thermocouples.

I looked at the chips - and they had same marking:

M31855K
1424A2
+780AB

(the modules have different white logo/text on them - from ali - CJMCU and from ebay - QiFEi.

And then I have found - only in one place over the internet where people are reporting the same problem with the same way marked chips.

The forum is in russian: http://radiokot.ru/forum/viewtopic.php?f=2&t=79526

So - be careful and beware of a fake modules!

Post a negative review on eBay or the seller's web site.

jremington - it's not about just "bad sellers" - I hope this may help some other people who got modules with chips or just chips from the same batch (with the same series marking).

I have lost a lot of time looking for info or thinking - "am I a fool" - but find reports only on a russian-speaking forum.

I have just wasted a day trying to make two of these eBay modules with the exact chips to work - no success. Thanks pliz for your info and link.

i have used MAX31855 MAX6675 SPI TypeK Thermocouple Temperature Sensor Module For Arduino MA sensor module and tried everything to run this but not getting appropriate answers https://github.com/adafruit/Adafruit-MAX31855-library/tree/master/examples/serialthermocouple used upper one link for code it is showing room temprature but not more than that

and https://github.com/adafruit/MAX6675-library/blob/master/examples/serialthermocouple/serialthermocouple.pde this one also by this one but not getting appropriate reading contact me at 8054665161

i have used MAX31855 MAX6675 SPI TypeK Thermocouple Temperature Sensor Module For Arduino MA sensor module and tried everything to run this but not getting appropriate answers https://github.com/adafruit/Adafruit-MAX31855-library/tree/master/examples/serialthermocouple used upper one link for code it is showing room temprature but not more than that

and https://github.com/adafruit/MAX6675-library/blob/master/examples/serialthermocouple/serialthermocouple.pde this one also by this one but not getting appropriate reading contact me at 8054665161

pliz: jremington - it's not about just "bad sellers" - I hope this may help some other people who got modules with chips or just chips from the same batch (with the same series marking).

I have lost a lot of time looking for info or thinking - "am I a fool" - but find reports only on a russian-speaking forum.

Chips are functionally tested before they are packaged - bad packaged chips are likely deliberate fraud, perhaps a different chip entirely from the markings, or sometimes a package without a chip inside...

Hi I bought one module on aliexpress with same problem only room temperature reading, I realised where was problem T- was connected to GND, You can check if it is not same problem by measuring resistivity between T- and GND, then using sharp scisors and cleaning path between pads on IC resistivity was changed and now it works. So it looks its PCB error. Bye

possible solution, see topic https://forum.arduino.cc/index.php?topic=553820.0