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Siemens SINUMERIK Controller
Spindle · Intermediate · 30-120 minutes
Siemens 840D 16112 - Channel block following spindle Impermissible programming
Alarm 16112 occurs when a following spindle (slave spindle in VV-coupling mode) receives impermissible motion programming beyond M3, M4, M5, and S commands. The SINUMERIK 840D spindle synchronization logic enforces strict velocity coupling constraints to maintain dimensional accuracy when position control is not active or properly configured.
16112
Siemens 840D 16112 - Channel block following spindle Impermissible programming
Channel block following spindle Impermissible programming
Siemens SINUMERIK 840D alarm 16112: Channel block following spindle Impermissible programming. This alarm indicates a program or channel-level error on the SINUMERIK control. The part program or machine function cannot be executed as commanded.
Root Cause Summary
Alarm 16112 occurs when a following spindle (slave spindle in VV-coupling mode) receives impermissible motion programming beyond M3, M4, M5, and S commands. The SINUMERIK 840D spindle synchronization logic enforces strict velocity coupling constraints to maintain dimensional accuracy when position control is not active or properly configured.
Safety
- Refer to Siemens documentation
- Ensure qualified technician performs repairs
Causes and Fixes
- 1
Review the NC program block %2 in channel %1. Identify any G01, G02, G03, or G00 commands targeting spindle %3.
Search for axis addresses (A, B, C) that correspond to the following spindle in the alarm block range.
- 2
Check machine data MD32000 (spindle assignment) and MD32100 (spindle coupling type) to confirm spindle %3 is configured as a following spindle in VV-coupling mode.
Verify coupling is set to VV (velocity-velocity) not EV (electronic-velocity) or other modes which have different restrictions.
- 3
Remove or restructure G-code motion commands on the following spindle. Replace with M3/M4/M5 and S-value commands only, or use separate program blocks if coupling needs to be deactivated.
- 4
Test corrected program on SINUMERIK Operate panel (Diagnose > Alarms) to verify block executes without 16112.
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