How to offset my temperatures (temperature deviation)

This article explains the steps of troubleshooting when temperatures in Cropster are not accurate in comparison to the readout on your roast machine.

About the temperature deviation in general

  • A slight deviation (up to 2°C/4ºF) can be normal depending on your setup (see below).
  • If the deviation is static (stays the same throughout the roast), an offset can be added within the Roasting Intelligence (RI) preferences.

Static vs. dynamic deviation

Static deviation

When the deviation is static, meaning the difference in temperature stays the same throughout the roast, an offset can be added.

  1. Navigate to the gear-png-2 Preferences on the bottom left side of the screen. 
  2. Select the Machine tab > Configuration.
  3. Add the difference in temperature to the Offset field under the affected temperature measurement.
    Screenshot 2024-07-04 at 11.17.27

Dynamic deviation

When the deviation is dynamic, meaning the temperature difference varies throughout the roast, focus on one readout (preferably the Cropster readout) only.

If the temperature deviation is significant, please contact us by creating a support ticket.

📚 Learn more about electrical interference and steps to troubleshoot.

Cropster Connector

If your roast machine is connected with the help of a Cropster Connector (Phidget), we have to differentiate how the probes are connected to the Cropster Connector. 

Splicing connection

There are many potential error sources when setting up a splicing connection.

The first step is to re-do the splicing connection. The wires have to be twirled very firmly. If they are too loosely twirled, a deviation is very likely. 

Dual probes

A dual probe has two temperature sensors on the inside.

One sensor is connected to the two leads that go into the machine's readout and one sensor is connected to the two leads that go into Cropster. 

Since the two sensors are measuring the temperature independently from each other, the temperatures are not completely aligned. A deviation of +-2°C/4ºF is likely.

Independent probe next to an existing probe

When there is an additional probe next to an existing probe installed, a deviation is very likely.

Two independent sensors are measuring the temperature.

The following variables can have an impact on the deviation:

  • Probe placement
  • Sheath thickness
  • Batch size
  • Probe age


Probe type

Is the probe type correctly assigned within the Roasting Intelligence (RI)?

  1. Navigate to the gear-png-2 Preferences on the bottom left side of the screen. 
  2. Select the Machine tab > Configuration.
  3. Check the Probe Type.

Check the ends of your thermocouple wires. From the colored coating of the wires, you can deduct the type of thermocouple.

Screenshot 2024-07-04 at 11.21.15

The physical connection

Make sure all wires are connected correctly.

The thermocouple leads have a positive and negative wire.

Ensure that all positive wires are connected and go into the positive port of the Cropster connector, and the same for the negative wires. 

Congratulations! You are now ready to offset your temperatures. 

Your opinion matters. If you have further questions, feedback, or concerns, please feel free to reach out by submitting a support ticket directly from