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Okuma OSP Controller
Servo/Axis · Intermediate
Okuma OSP Alarm D 4165 - MCS Encoder initialization failure
The motor encoder on the axis or spindle named in the object failed to initialize at power-up. The code identifies at which communication step initialization stopped and the kind of error, so the axis has no position feedback until it completes.
4165
Okuma OSP Alarm D 4165 - MCS Encoder initialization failure
MCS Encoder initialization failure
The motor encoder on the axis or spindle named in the object failed to initialize at power-up. The code identifies at which communication step initialization stopped and the kind of error, so the axis has no position feedback until it completes.
Common Causes
- Motor encoder failure
- Encoder link cable or connector fault
- Inverter unit control board problem
- Encoder parameter mismatch (multi-rotation range or communication info)
Troubleshooting Steps
- 1Read the code number shown with the alarm: code XX = Encoder link sequence step at detection: 0=reset, 1=network address, 2=basic comm info, 3=comm version change, 4=device info, 5=parameter change, 6=AT mode start.; code YY = Error content: 0=communication error, 1=TX start time over, 2=TX finish time over, 3=RX finish time over, 4=abnormal response address, 5=abnormal response code, 6=parameter error.; code ZZZZ = Additional data: C2ERR status, frame info, responding address, received frame, or parameter number depending on YY.
- 2Read the code: XX is the link sequence step (0 reset, 1 network address setting, 2 basic communication info request, 3 communication version change, 4 device info acquisition, 5 parameter change, 6 AT mode start); YY is the error content (0 communication error, 1-3 time overs, 4 abnormal response address, 5 abnormal response code, 6 parameter error).
- 3If YY is 6, read ZZZZ: 1 means not all necessary parameters received, 2 means basic communication info incompatible, 3 means multi-rotation detection range mismatch, which points to a parameter or encoder-type mismatch rather than hardware.
- 4Inspect the encoder link cables and connectors between the motor encoder and the inverter unit for damage, oil or bent pins and reseat both ends.
- 5Swap the encoder link cable with a known-good cable, then cycle power and watch whether initialization passes the step shown in XX.
- 6If wiring is good, substitute the motor encoder with a known-good unit; if still failing, have the inverter unit control board checked, then re-home the axis.
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