Overview 

This article explains how to troubleshoot temperature deviation between your roaster and Cropster across Phidget and Cropster Connector setups.

Instructions

To troubleshoot effectively, first identify which of these two categories the deviation falls into:

1. Minor deviation: This can occur naturally, depending on the setup. 
2. Major deviation: This might indicate a setup error. 

Minor deviation (< 5°C / 9 F)

A minor deviation of up to 5°C / 9°F) is often normal and typically stem from:

• Splicing connection: 
  Spliced wires can slightly alter the electrical signal, causing small temperature errors. If the temperature difference stays the same during the whole roast, you can simply add an offset in Cropster to match them up. Alternatively, we recommend ignoring the difference and relying solely on the Cropster readout for consistency.
   
• Your sensor configuration:
  When you add a second temperature probe to your machine, it is normal for the two readings not to match perfectly. 
  Here is why and how to get the most accurate results:
  • The temperature inside a roasting drum isn't the same everywhere. Even moving a probe by an inch can change the reading.
  • To get readings that match as closely as possible, place your new probe right next to the original one.
  • Use probes that are identical in type, length, and thickness. If one is thicker than the other, it will heat up more slowly, causing the temperatures to look different.
  •  Even "dual probes" (one housing with two sensors inside) can have slight differences because they are still two separate sensors doing their own work.

Major deviation 

A major deviation occurs when the temperature readings between the machine and Cropster differ by more than 5°C or 9°F.

A significant temperature variance may be attributed to several factors. Key areas to investigate include:

1. Physical connection
2. Roasting Intelligence configuration

Physical connection

Temperature differences are often caused by wires that are either connected to the wrong ports or joined together incorrectly.

Think of your thermocouple cable like a battery—it has a positive and a negative wire that both need to go to the right spot:

• The Negative Wire: This must be connected to the port labeled "G".
• The Positive Wire: This must be connected to the numbered port (for example, port 1 or 2).

If these wires are swapped or loose, your temperature readings will be inaccurate. 
You can see exactly how to line them up in the K-type thermocouple example below:

When joining (splicing) wires together, the most important thing is to match the polarity. If the wires are mixed up, your temperature readings will be wrong.

Follow these steps to ensure a correct connection:

1. Ensure the positive (+) lead from your probe is connected to the positive (+) lead of the extension wire.
2. Similarly, connect the negative (-) lead to the negative (-) lead.
   

   

3. Double-check that you haven't accidentally crossed them (+ to -), as this is the most common cause of inaccurate data.
    

Roasting Intelligence Configuration

If you are using a Type K probe but the software is set to Type J, your temperatures will be significantly off.

Ensure the correct thermocouple type is selected in the Roasting Intelligence settings: 

1. Log in to Roasting Intelligence.
2. Navigate toPreferences > Machine tab  > Measurements.
3. The 'Type' configuration can be found in the center section of the display.
   

   

    

Contacting Customer Support

Please create a support ticket via support.cropster.com and provide the following information:

• A general description of the problem (how big is the deviation, is it static or dynamic, etc.)
• Pictures of the physical connection (Cropster connector, Thermocouple wires, splicing connection, etc.)
• Roasting Intelligence Log files 

If you have further questions, feedback, or concerns, please submit a support ticket directly from support.cropster.com.