Yaskawa Alarm Code Reference

Yaskawa alarm A.710 is an encoder communication error on Sigma-7 servo drives. It indicates that serial communication between the servo motor encoder and the servo drive has failed. Common causes include encoder cable (CN2) disconnection, connector contact failure, shield grounding issues, or electromagnetic noise interference from nearby power cables. To resolve it, reconnect the CN2 connector, inspect the cable for physical damage, verify single-point shield grounding, route encoder cables separately from power lines, and consider motor replacement if the encoder itself is faulty.

To reset a Sigma-7 servo alarm: first identify the specific alarm code on the drive display or through SigmaWin+ software. Address the root cause (e.g., fix cabling for A.710, reduce load for A.050, check power supply for A.030). Then use the alarm reset function Fn001 through the panel operator or SigmaWin+. If the alarm persists after reset, power cycle the servo drive. Safety-related alarms (S-STO1, S-EMG1) require physically releasing safety inputs before they can be cleared.

Motoman alarm 4101 is a servo emergency stop on YRC1000 or DX200 robot controllers. It triggers when any emergency stop circuit is opened: the teach pendant E-stop button, the control cabinet E-stop button, a safety fence interlock door, or an external emergency stop circuit (EXESP). To resume, release all E-stop sources, verify all safety interlocks are satisfied, check the safety PLC interlocking status, and then execute the servo ON command.

Alarm A.02B fires when the difference between the commanded position and actual encoder position exceeds the threshold set in parameter Pn520. Root causes include excessive mechanical load (worn ball screw, poor guide lubrication), insufficient servo gain settings, or motor torque saturation. Troubleshoot by inspecting mechanical components, adjusting position loop gain (Pn100) and velocity loop gain (Pn101), setting an appropriate Pn520 detection level, reducing feed rate, and running auto-tuning (Fn002).

CPF01, CPF02, and CPF03 indicate overcurrent (over 200% of rated current) during acceleration, deceleration, and constant speed respectively. For CPF01, increase the acceleration time (C1-01). For CPF02, increase deceleration time (C1-02) and verify braking resistor installation. For CPF03, investigate sudden load changes and check motor wiring. In all cases, inspect motor cables for short circuits, measure insulation resistance, check V/f pattern settings (E1-03 to E1-10), and verify the load is within inverter capacity.

C-ML01 is a communication timeout indicating physical cable problems, missing termination resistors, or slave device failure. C-ML02 means a configured slave station was not detected, usually from a station number mismatch (check the rotary switch), cable disconnection, or device power-off. For both alarms, verify cable connections, ensure terminators are installed at both ends, confirm cable length is within the 50m specification, and check that station numbers match between master and slave configurations.

The reference covers seven safety function codes: S-EMG1 (emergency stop circuit open), S-STO1 (Safe Torque Off activated), S-SS1 (Safe Stop 1 — deceleration stop then STO), S-SLS1 (Safely Limited Speed violation), S-SLP1 (Safely Limited Position violation), S-SBC1 (Safe Brake Control error), and S-ERR1 (safety module internal FSoE error). Each entry explains the trigger condition and provides a 5-step resolution procedure including safety parameter verification and FSoE communication diagnostics.

Yes. All alarm code data is embedded directly in the browser application and the search runs entirely client-side. No search queries, alarm codes, or diagnostic information is ever transmitted to a server, stored in a database, or shared with third parties. The tool works offline after the initial page load, making it suitable for use in secure factory environments with restricted network access.