Control-to-power interface

ABB ACS800 RMIO to INT/AINT Interface Relationship

Carries control-to-inverter interface communication and status used in PPCC LINK troubleshooting.

Practice-oriented technical reference8 min read

Scope of this technical record

Board relationship record for the ACS800 control-to-inverter interface path that underpins PPCC LINK diagnosis.

Safety boundary

This page maps board functions; it is not a live-probing instruction. Internal interface work requires isolation, antistatic handling and model-specific service documentation.

Functional boundary

The RMIO board represents the motor-control and I/O side of the ACS800 control system. The INT or AINT interface electronics represent the power-unit communication and localisation boundary. Between them lies the PPCC communication context that becomes visible when the drive reports PPCC LINK or internally localised inverter-unit faults.

This division is operationally useful. A panel fault that originates because RMIO lacks its expected supply, a link is interrupted, or an interface board is not responding should not be diagnosed using the same sequence as a confirmed output-bridge short.

Evidence available from firmware

In parallel inverter systems, the FAULTED INT INFO word provides a structured location map: individual INT board fault bits and a PBU branching-unit fault bit. The same architecture allows a technician to map a reported PPCC LINK branch to a physical module rather than substituting components across an entire cabinet.

For short-circuit investigation, INT SC INFO adds phase-leg information. Together these words support a high-value repair workflow: identify the communication branch, identify any switching-leg evidence, then correlate board inspection and parts decisions with that evidence.

Board relationship and symptom routing

ElementFunction in diagnosisAssociated symptom family
RMIOControl logic, I/O and control supply contextLoss of control/interfacing or configuration context
INT / AINTMain-circuit interface and internal localisationPPCC LINK, interface hardware status, short-circuit location
PBULink branching in parallel inverter unitsNumbered branch faults or branching-unit fault
Gate-driver / IGBT assemblyActual power switching boundarySHORT CIRC and recurrent destructive failure

Service decision logic

A board exchange is justified only after the supply arrangement, link medium and module identity have been established. An interface board can be a genuine failure, but it can also be a victim of upstream supply disturbance or downstream destructive damage. Label and photograph all connectors before disturbance and preserve the original failure record for the post-repair test report.

Where an AINT hardware or measurement-scaling indication is active, replacement decisions require the exact unit documentation and compatible board revision. A database page can route the fault; it must not imply universal cross-compatibility between boards that appear visually similar.

Board handling and compatibility discipline

Control and interface boards should be handled as revision-controlled assemblies rather than anonymous circuit cards. Before removal, capture label, revision and connector orientation evidence, and ensure that optical or electrical links can be restored to their original branch. In a multi-module cabinet, an accidental branch swap may introduce a new diagnostic problem that did not exist before the repair attempt.

Compatibility must be established from the installed drive documentation or verified interchange data. Even where a supplier lists a board under the ACS800 family, the technician must still confirm frame/application context and associated firmware or measurement limitations. IndustrialDriveData should record proven matches and successful outcomes over time; it should not turn market listings into universal compatibility claims.

Field record checklist

  • Determine whether the drive uses a single or parallel inverter arrangement.
  • Capture FAULTED INT INFO and INT SC INFO where available.
  • Verify RMIO power and supply configuration context.
  • Trace the indicated link branch before replacing interface or driver hardware.

Technical basis and reference documents

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

ACS800 Standard Control Program Firmware ManualABB

Fault tracing, PPCC LINK (5210), SHORT CIRC (2340), FAULTED INT INFO and INT SC INFO.

Linked circuit records