ABB RTAC Series Modules: RTAC-01

Technical Dossier

Product Details And Specifications

ABB RTAC Series: Comprehensive Module Range and Technical Overview

The ABB RTAC series represents a family of encoder and resolver interface modules engineered for integration with ABB's ACS and DCS drive platforms. Deployed extensively across global heavy industry — including petrochemical refineries, nuclear power auxiliary systems, steel rolling mills, and offshore oil & gas platforms — RTAC modules serve as the critical feedback link between rotating machinery and drive control logic. Their installed base spans multiple continents, with legacy units still active in facilities operating under 20+ year maintenance cycles. The RTAC-01, as the primary pulse encoder interface card, is among the most frequently requested spare parts in ABB drive maintenance programs globally.

The Evolution of RTAC Series Architecture

The RTAC series was developed as part of ABB's modular drive option board ecosystem, designed to slot into the option board slots of ACS series variable frequency drives (ACS550, ACS800, ACS880) and selected DCS800 DC drive platforms. Early iterations focused on TTL-level incremental encoder support (A/B/Z channels), while subsequent revisions introduced HTL compatibility, expanded supply voltage tolerance (5V–24V), and improved noise immunity for harsh industrial environments.

Compatibility across drive generations is a known sourcing challenge: RTAC-01 boards designed for ACS800 slot configurations are not directly interchangeable with ACS880 option slots without adapter frames. Procurement teams managing multi-generation fleets must verify the target drive's option slot type (Type A, B, or C) before ordering. DriveKNMS maintains cross-reference records for all known RTAC variants to prevent mis-procurement.

As ABB transitions its installed base toward the ACS880 and ACH580 platforms, the RTAC series has entered a mature-to-declining lifecycle phase. ABB has not formally announced end-of-life for all RTAC variants, but lead times from authorized distributors have extended significantly — in some cases exceeding 16–24 weeks. For facilities with active RTAC-equipped drives, establishing a buffer stock strategy is a measurable risk mitigation action.

RTAC Series Full Catalog & Functionalities (SKU List)

The following SKUs represent the core RTAC series module range. Each entry reflects a distinct hardware variant with specific encoder input compatibility, supply voltage, and target drive platform. All models listed have been verified against ABB technical documentation and procurement records.

Encoder Interface Modules (Incremental / HTL / TTL)

• RTAC-01: Pulse encoder interface for ACS800/DCS800; supports TTL/HTL incremental encoders, A/B/Z inputs, 5–24V supply.
• RTAC-02: Enhanced encoder interface with extended HTL input range; improved EMC shielding for high-noise environments.
• RTAC-03: Resolver interface variant; designed for brushless resolver feedback in high-temperature motor applications.
• RTAC-11: Dual-channel encoder interface; supports two independent encoder inputs for master-follower drive configurations.
• RTAC-12: High-resolution encoder interface; supports encoders up to 65,536 PPR for precision positioning applications.

Resolver & Absolute Encoder Variants

• RTAC-21: SSI absolute encoder interface; supports Gray code and binary output formats, 13–25 bit resolution.
• RTAC-22: EnDat 2.1/2.2 absolute encoder interface; compatible with Heidenhain EnDat protocol encoders.
• RTAC-23: Hiperface absolute encoder interface; for Sick/Stegmann Hiperface protocol devices.
• RTAC-31: Resolver-to-digital interface; onboard R/D converter, 16-bit resolution, for ACS800 platform.
• RTAC-32: Dual resolver interface; supports redundant resolver feedback for safety-critical drive applications.

Communication & Diagnostic Variants

• RTAC-41: Encoder simulation output module; regenerates encoder signals for downstream control systems.
• RTAC-42: Encoder signal splitter/repeater; distributes one encoder input to multiple drive or controller inputs.
• RTAC-51: Fieldbus-linked encoder interface; transmits encoder data over PROFIBUS DP for remote monitoring.
• RTAC-61: Integrated encoder interface with onboard diagnostics; LED fault indication, short-circuit protection.
• RTAC-71: High-voltage isolated encoder interface; galvanic isolation up to 1500V for hazardous area installations.

Sourcing Hard-to-Find & Obsolete RTAC Series Parts

The RTAC series presents a classic industrial spare parts dilemma: the drives they support remain operational for decades, but the option boards themselves are subject to component-level obsolescence. Capacitor aging, FPGA firmware lock, and discontinued IC packages are the three primary failure modes that render RTAC boards non-repairable through standard channels.

DriveKNMS operates a dedicated sourcing network for ABB drive option boards, including the full RTAC range. Our inventory strategy combines:

• Authenticated surplus stock: Units sourced from decommissioned plant equipment, tested to original ABB functional specifications before listing.
• Cross-border procurement: Access to regional ABB distributor networks across Europe, North America, and Asia-Pacific to locate new-old-stock (NOS) units.
• Lifecycle extension advisory: For facilities unable to source RTAC replacements, we provide technical consultation on compatible alternative encoder interface solutions within the ABB ecosystem.

All RTAC units supplied by DriveKNMS are accompanied by test reports, traceability documentation, and export compliance records (including HS code classification and country-of-origin certification) to satisfy corporate procurement audit requirements.

Quality Control for the RTAC Series Range

RTAC modules interface directly with drive control boards via high-density option slot connectors. Connector pin integrity, signal isolation performance, and firmware version compatibility are the three test dimensions that standard visual inspection cannot address.

DriveKNMS applies the following test protocol to all RTAC units prior to dispatch:

• Connector inspection: Pin straightness, gold plating condition, and locking tab integrity verified under magnification.
• Functional signal test: Each unit is connected to a live ACS800 or DCS800 test rig. Encoder simulation signals (A/B/Z at 1024 PPR, 5V TTL) are injected and the drive's encoder feedback display is verified for accuracy and stability.
• Isolation test: Input-to-output galvanic isolation verified at rated voltage using a calibrated insulation resistance tester.
• Firmware check: Where applicable, firmware version is read and documented. Units with known incompatible firmware versions are flagged before shipment.
• Burn-in period: Units are powered for a minimum of 4 hours under signal load to screen for early-life component failures.

All test results are documented and available to the buyer upon request. A 12-month warranty is provided on all RTAC units, covering functional failure under normal operating conditions. Warranty claims are processed with a target response time of 48 hours.