When operating normally or encountering an issue, the controller’s 7-segment display cycles through up to four characters to convey its current mode, errors, or warnings. Understanding this display is the first step in any diagnostic process. For instance, an 'H' displayed during operation indicates that the "Safe Torque Off" (STO) safety function has been requested. A bootloader error is indicated by the display 'B L E'.
Here is the master table of codes you will encounter. Note that when we refer to "blink codes," count the number of short flashes, followed by a long pause.
The CMMO-ST-C5-1-DIOP supports the "Safe Torque Off" (STO) safety function, which is critical for preventing unexpected motor startup. Its status is shown on the 7-segment display with the letter 'H'.
is a compact, versatile stepper motor controller designed for position, speed, and torque control. It relies on an integrated to communicate system events, warnings, and hard faults. cmmo-st-c5-1-diop error codes
The following table compiles some of the most frequently encountered diagnostic messages. This list is not exhaustive, and you should always refer to the official Festo documentation for the most current and complete information.
| Error Code (Hex) | Description | Troubleshooting Steps | | :--- | :--- | :--- | | | Motor Temperature Fault | 1. Motor is overheated. Allow it to cool. 2. If motor is cold, check the wiring of the temperature sensor (PTC/KTY) to the controller. 3. Verify parameter settings match the actual motor type. | | 0x8501 | Short Circuit (Output Stage) | 1. WARNING: Do not reset immediately. Disconnect motor cables. 2. Check for short circuits between U/V/W phases or to ground. 3. If wiring is good, the internal IGBTs may be blown. | | 0x8600 | Following Error (Lag Error) | The motor cannot reach the target position. 1. Mechanical Load: Check for jamming or increased friction. 2. PID Tuning: Increase Position Gain (Kp) or Velocity Gain. 3. Torque: The motor may be undersized for the application. | | 0x8700 | Limit Switch Triggered | 1. The axis hit a physical limit switch unexpectedly. 2. Move the axis away from the limit manually (jogging) before resetting. 3. Check the logic of the limit switch wiring (NC vs NO). | | 0x8xxx | Stall Detected | 1. The motor stopped moving while voltage was applied. 2. Check for mechanical blockages. 3. Increase motor current limit (if thermal safe). 4. Check the "Stall Detection Threshold" parameter. |
Short circuits in the motor phases or overheating of the controller. Over-temperature When operating normally or encountering an issue, the
The system displays a warning but operation continues. The warning disappears automatically once the cause is resolved.
Below is an overview of the error categories and common codes you might encounter with this device. Understanding the CMMO-ST Error System
These codes occur when the motor's physical path deviates from the commanded target path. CMMO-ST-C5-1-DIOP/DION - Festo A bootloader error is indicated by the display 'B L E'
The table below compiles the most common diagnostic messages for the CMMO-ST-C5-1-DIOP. Each entry includes the error number, a description, probable causes, recommended actions, and the default error response (code letter). Please note that some error responses can be parameterized in the FCT.
Critical internal hardware failures or firmware corruptions require a complete logic power cycle ([X9] terminal) to reset. Critical Error Code Categories and Troubleshooting 1. Hardware and Voltage Failures (0x01–0x0F)
When an error occurs, the controller can respond in several ways. These are identified by code letters through G , and they define the stopping behavior and whether the output stage is turned off.
: Drag error monitoring (following error) and software end-position detection. Hardware Protection : I2tcap I squared t