IndustrialDriveDataDrive Board & Diagnostic Database
Speed feedback / CUD1 interface service evidence

Siemens SIMOREG 6RA70 Tachometer / Encoder / CUD1 Evidence Record

Collects the evidence needed before changing speed-feedback hardware, rerunning optimization, installing donor CUD1 hardware or modernizing a SIMOREG 6RA70 DC drive.

Board evidence record8 min read

Scope of this technical record

Evidence record for tachometer, encoder, CUD1 feedback input, parameter memory and optimization-run service decisions.

Safety boundary

Qualified personnel only. Do not run a production DC motor on an unknown feedback or parameter configuration.

6RA70 feedback evidence record

1Device
→
2Terminals
→
3Scaling
→
4CUD1 label
→
5Fault value
→
6Decision

The record collects feedback and optimization evidence before repair or modernization.

6RA70 feedback evidence record

Siemens 6RA70 tachometer encoder CUD1 evidence record
The record supports repair, donor-board or modernization decisions.

Evidence required before service

Useful photos and notes show feedback device type, terminal wiring, shielding, CUD1 label, PMU state, parameter backup status, selected optimization run and fault value. This package supports repair, donor-board or modernization decisions without hiding feedback or parameter errors.

Field record checklist

  • Tach / encoder evidence
  • Terminal photos
  • CUD1 label
  • PMU state
  • Parameter backup
  • Run type
  • Fault value
  • Actual speed behavior

Technical basis and reference documents

This is an independent editorial technical reference. Original manufacturer documentation remains controlling for installation, repair and commissioning decisions.

FAQ for 6RA70 DC MASTER and SIMOREG CM fault diagnosticsSiemens Industry Support

OEM troubleshooting reference for 6RA70 fault values, tachometer checks, CUD1 / power-interface context and optimization-run faults.

SIMOREG DC-MASTER 6RA70 operating instructionsSiemens / SIMOREG documentation archive

Base operating and commissioning context for SIMOREG DC-MASTER converters, parameterization and speed-sensing setup.

Linked circuit records

Circuit
Siemens SIMOREG 6RA70 Optimization Run Preconditions Path

Maps F050-style optimization failures through selected run type, commissioning order, motor data, armature current build-up, field proof, load isolation and feedback credibility before a control-board decision.

Open →Circuit
Siemens SIMOREG 6RA70 Speed Feedback and Tachometer Path

Separates speed-feedback instability into selected feedback source, analog tachometer polarity and voltage, encoder pulse evidence, wiring, shielding, mechanical coupling and CUD1 feedback input boundaries.

Open →Circuit
Siemens SIMOREG 6RA70 CUD1 Parameter Memory and Commissioning Path

Maps F051-style optimization setup problems and donor-board cases through parameter access, permanent memory, parameter backup, PMU access, electronics stability and CUD1 replacement evidence.

Open →
Evidence intake

Turn this record into a qualified service request

A repair decision is much more reliable when the request includes the exact identity of the drive, the first fault evidence and the machine condition when the symptom appeared.

  • Complete drive type code / MLFB or nameplate model
  • Fault code, fault value and first event before reset
  • When the event appears: power-up, enable, ramp, run, decel or stop
  • Motor/cable connected or isolated during the symptom
  • Visible board, option-card, module and connector identifiers
  • Previous repair history, replacement parts and repeat-failure pattern
Prepare request →