Adjust your position window and acceptable following error tolerances in the FCT parameterization menu.
Incorrect power supply voltage (must be 24V DC ± 15%), or the motor is generating too much power during braking (e.g., stopping a high-inertia load too quickly). Troubleshooting: Measure input voltage at [X9].
controllers were humming along, managing the precise movements of the stepper motors. Suddenly, the lead technician, Elias, noticed a line had stopped. He hurried to the control cabinet and saw a flashing red light on one of the units. 1. The Mysterious "E047" Elias looked at the tiny display. It flashed
Verify that both safety channels are receiving identical signals. Inspect the safety relay or PLC output providing the STO signal. 3. Communication Timeout
The CMMO-ST-C5-1-DIOP Manual contains a comprehensive diagnostic chapter listing every code. cmmo-st-c5-1-diop error codes
Toggle the "Reset" bit in your PLC control word or use the FCT software to clear resettable faults.
When a fault occurs, the motor controller enters an error status, and the error must be managed appropriately.
Indicates the function has been requested or is active. Operational Status Pxxx
: Indicates a Fault (Error). These have the highest priority and must be acknowledged before operation can resume. Adjust your position window and acceptable following error
Use this guide to identify, diagnose, and resolve common error codes for this device family.
Internal firmware stack overflow or execution timeout.
: A display flashing continuous H segments indicates that the Safe Torque Off (STO) safety circuit has been triggered. This drops power to the motor coils immediately to safeguard operators. Core Diagnostic Error Categories
Ensure all motor cables and encoder cables are properly shielded, and the shielding is correctly grounded to the chassis or mounting plate. Electromagnetic interference (EMI) can result in seemingly random encoder errors or communication faults. Parameterization Setup issue
: Specific documentation for errors related to the Safe Torque Off (STO) safety function. Motor controllers CMMO-ST - Festo Didactic Infoportal
Note that this model is being discontinued (available until 2026) and is officially replaced by the CMMT-ST-C8-1C-EC-S0 .
Errors on the CMMO-ST series are generally categorized by their prefix and impact on operation: Code Prefix Action Level Immediate stop; requires a reset (CCON.RESET). Informational; does not necessarily stop movement. Parameterization Setup issue; check FCT (Festo Configuration Tool) settings. 2. Frequent Error Codes & Troubleshooting
The Festo CMMO-ST-C5-1-DIOP Go to product viewer dialog for this item.