No PT1000 with MAX31865

ESPHome
1

I try to use PT1000 with a MAX31865. No matter, what I set up, it only recognizes PT100. When I connect a 120Ω resistance as sensor, it gets 48°C. When I use a 1000Ω, it says “RTD High Threshold between measurements”.
The reference resistor is 4700Ω.
Does anybody know, what I do wrong?

spi:
  clk_pin: GPIO14
  miso_pin: GPIO12
  mosi_pin: GPIO13

sensor:
  - platform: max31865
    name: "BBQ Temperature"
    icon: "mdi:hamburger"
    cs_pin: GPIO15
    reference_resistance: "4300 Ω"
    rtd_nominal_resistance: "1000 Ω"

the log output with the 120Ω connected is

[21:29:42][D][sensor:093]: 'BBQ Temperature': Sending state 48.52332 °C with 2 decimals of accuracy

with a 1000Ω it’s

[21:15:47][W][max31865:034]: RTD High Threshold between measurements
[21:15:47][E][max31865:101]: SPI bus read all 0 or all 1 (0xFFFF), check MAX31865 wiring & power.
[21:15:47][D][sensor:093]: 'BBQ Temperature': Sending state nan °C with 2 decimals of accuracy

even changing the default values back to 470Ω / 100Ω doesn’t seem to have an effect.

Thanks for any suggestions

2

The solution is a beginners mistake. User sbrk-r have me the hint, that 4700 means 470, not 4700 ohms.
I had a 4701 right next to it and didn’t realize.
I’m pretty sure after soldering the correct resistor, it will work properly.

Thanks for your help

3

Unless you’ve got impeccable soldering skills, changing the resistor from a 4700 to a 4701 is a nightmare.

I destroyed 2 MAX31865 boards this way, and countless resistors. Eventually I gave up and bought the rarer & more expensive 4701 version.