FaultResolve
Back to Search Directory
Search this section

Search Siemens SINUMERIK 840D CNC

Search other Siemens SINUMERIK 840D CNC alarms without going back to the model list.

Search all database

Code 112420: Error on changing over inch/metric!%nCheck all data!

Issue Description & Safety Warning

The Siemens SINUMERIK 840D CNC has triggered a critical Error on changing over inch/metric!%nCheck all data! alarm. Immediate attention from a qualified operator or maintenance technician is required to prevent secondary damage to the equipment or spoiled parts during the manufacturing cycle. Always ensure standard safety and LOTO procedures are followed before accessing electrical cabinets.

Official Troubleshooting Steps

Definitions: The switchover of the data for the in ch/metric conversion was not completed. This alarm can only appear in the event of hardware defects. Reaction: NC Start disable in this channel. Alarm display. Remedy: The following data must be checked: Display MD's: MD9655: $MM_CMM_CYC_PECKING_DIST MD9656: $MM_CMM_CYC_DRILL_RELEASE_DIST MD9658: $MM_CMM_CYC_MIN_COUNT_PO_TO_RAD MD9664: $MM_CMM_MAX_INP_FEED_P_MIN MD9665: $MM_CMM_MAX_INP_FEED_P_ROT MD9666: $MM_CMM_MAX_INP_FEED_P_TOOTH MD9670: $MM_CMM_START_RAD_CONTOUR_POCKET MD9752: $MM_CMM_MEASURING_DISTANCE MD9753: $MM_CMM_MEAS_DIST_MAN MD9754: $MM_CMM_MEAS_DIST_TOOL_LENGTH MD9755: $MM_CMM_MEAS_DIST_TOOL_RADIUS HMI-Alarms MD9756: $MM_CMM_MEASURING_FEED MD9757: $MM_CMM_FEED_WITH_COLL_CTRL MD9758: $MM_CMM_POS_FEED_WITH_COLL_CTRL MD9759: $MM_CMM_MAX_CIRC_SPEED_ROT_SP MD9761: $MM_CMM_MIN_FEED_ROT_SP MD9762: $MM_CMM_MEAS_TOL_ROT_SP MD9765: $MM_CMM_T_PROBE_DIAM_LENGTH_MEAS MD9766: $MM_CMM_T_PROBE_DIAM_RAD_MEAS MD9767: $MM_CMM_T_PROBE_DIST_RAD_MEAS MD10240: $MN_SCALING_SYSTEM_IS_METRIC MD20150 [12]: $MC_GCODE_RESET_VALUES Tool data for various cutting edges D: length Z, radius R, wear length radius Z and R. Zero offsets: Basic offset position in X, Y, Z, as well as A, C (if available) zero offset. Settings in operating mode MANUAL: Retraction plane, safety clearance. Program Continuation: Internal

Source: SINUMERIK 840D sl / 840Di sl / SINAMICS S120 Diagnostics Manual (DAsl, 03/2009)

Last reviewed: 2026-07-01 · Verified against the manufacturer’s official documentation.

About Siemens SINUMERIK 840D CNC Alarms

Siemens controllers include extensive self-diagnostics that flag or halt the machine when a fault is detected. Error code 112420 on the SINUMERIK 840D CNC identifies one specific fault condition — its documented cause and the official corrective steps are listed above, sourced from Siemens's service documentation. Always confirm against the manual for your exact machine configuration and follow LOTO procedures before servicing.

Complete Alarm List: 4014 Siemens SINUMERIK 840D CNC codes.

Have a better solution?

Help the industrial community by sharing your repair experience for code 112420.

Manual conversion service

Need a searchable reference for more Siemens SINUMERIK 840D CNC manuals?

We structure equipment manuals into searchable code, title, cause, solution, safety note, and source-reference data. Send a PDF and example searched codes when you need public pages, private search, or structured exports.

Convert PDF fault-code charts and manuals into clean data.
Build public SEO pages or private internal search tools.
Prioritize updates around codes and manuals people search for.
Request manual conversion Email PDFs to manuals.errordb@gmail.com
Advertisement

Space reserved for Google AdSense / Industrial Affiliate Links

Monetization target for 2026

Related Siemens SINUMERIK 840D CNC Codes