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Siemens SINUMERIK Controller
Program/G-code · Intermediate · 30-120 minutes
Siemens 840D 101627 - Write access only in start-up state Encoder (p10=4).
Alarm 101627 occurs when attempting to modify encoder-related machine data parameters that are write-protected during normal operation. These parameters can only be changed when the control is in start-up mode (p10=4), which is a protected state requiring specific authorization and system conditions.
101627
Siemens 840D 101627 - Write access only in start-up state Encoder (p10=4).
Write access only in start-up state Encoder (p10=4).
Siemens SINUMERIK operator message 101627: Write access only in start-up state Encoder (p10=4). This is an informational message from the SINUMERIK control indicating a system status or operation result that may require operator action.
Root Cause Summary
Alarm 101627 occurs when attempting to modify encoder-related machine data parameters that are write-protected during normal operation. These parameters can only be changed when the control is in start-up mode (p10=4), which is a protected state requiring specific authorization and system conditions.
Safety
- Refer to Siemens documentation
- Ensure qualified technician performs repairs
Causes and Fixes
- 1
Identify which encoder parameter (machine data) triggered the alarm by checking the detailed alarm information in the alarm buffer.
- 2
Set the control to start-up mode: Switch keyswitch to position 3 or set $MN_PASSWD_LEVEL_2 with appropriate password level.
Changing encoder parameters requires machine recalibration. Document current settings before making changes.
- 3
Modify the required encoder machine data parameter while in start-up mode.
- 4
Perform a RESET and power cycle (Power OFF/ON) to activate the changes, then perform reference point approach for affected axes.
All axes will lose their reference position. Ensure machine is in safe position before power cycling.
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Always verify with your machine manual or a certified technician before performing service procedures.