ABB NKAS Series Modules — NKAS01-15 Analog Module TU Cable

Technical Dossier

Product Details And Specifications

ABB NKAS Series: Comprehensive Module Range and Technical Overview

The ABB NKAS series comprises termination unit (TU) cables and analog signal interface accessories designed for use within the ABB Advant Controller 800M (AC800M) and S800 I/O distributed control system architecture. These components are deployed across global heavy industry installations including petrochemical refineries, nuclear power facilities, offshore platforms, and large-scale chemical processing plants. The NKAS series serves as the physical signal interconnect layer between field instruments and S800 I/O modules, enabling reliable analog and digital signal transmission in high-availability process control environments. Installed base spans multiple decades of continuous operation, making lifecycle parts availability a critical procurement concern for plant maintenance engineers worldwide.

The Evolution of NKAS Architecture

The NKAS cable series was introduced alongside ABB's S800 I/O system in the mid-1990s as part of the Advant OCS platform. Early variants were designed for the Advant Controller 110 (AC110) and AC450 environments, providing passive cable interconnects between I/O modules and field terminal units. With the transition to the AC800M platform (introduced circa 1999–2001), the NKAS series was extended and standardized to support the ModuleBus backplane communication architecture. The cables interface S800 I/O modules — including AI810, AO810, DI810, DO810, and their successor variants — to TB820 and TB840 ModuleBus Termination Units and associated field wiring panels.

As ABB migrated customers toward the AC800M with S800 I/O and later toward the System 800xA DCS environment, the NKAS cable range remained backward-compatible across generations, a deliberate design choice that extended the operational lifespan of existing field wiring infrastructure. By the 2010s, several NKAS variants entered the mature/end-of-active-production phase. ABB's official spare parts program continues to list select NKAS items, but procurement lead times have extended significantly, making third-party MRO suppliers a primary sourcing channel for plant turnaround and emergency maintenance scenarios.

NKAS Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly referenced models within the ABB NKAS series. Each entry reflects a distinct cable length, connector configuration, or termination unit compatibility variant:

NKAS01-15: 1.5 m TU cable for S800 analog I/O module to field terminal unit interconnect.
NKAS01-30: 3.0 m TU cable, extended reach for panel-to-module analog signal routing.
NKAS01-50: 5.0 m TU cable for increased cabinet depth or remote mounting configurations.
NKAS01-100: 10.0 m TU cable for long-distance analog signal runs within control room enclosures.
NKAS02-15: 1.5 m TU cable variant for digital I/O module termination unit interface.
NKAS02-30: 3.0 m digital I/O TU cable, compatible with DI810/DO810 module families.
NKAS02-50: 5.0 m digital I/O TU cable for extended panel wiring configurations.
NKAS03-15: 1.5 m cable for TB820 ModuleBus Termination Unit to S800 I/O module connection.
NKAS03-30: 3.0 m TB820-compatible TU cable for standard rack-to-field wiring.
NKAS03-50: 5.0 m TB820-compatible TU cable for deep enclosure or remote I/O panel use.
NKAS04-15: 1.5 m cable for TB840 redundant ModuleBus Termination Unit configurations.
NKAS04-30: 3.0 m TB840-compatible TU cable supporting redundant I/O architectures.
NKAS05-15: 1.5 m cable for AI835/AI845 HART-enabled analog input module termination.
NKAS05-30: 3.0 m HART analog input TU cable for AI835/AI845 module families.
NKAS06-15: 1.5 m cable for AO845 HART analog output module to field terminal unit.
NKAS06-30: 3.0 m AO845-compatible TU cable for extended analog output signal routing.
NKAS07-15: 1.5 m cable for temperature input modules (TU810/TU830) in thermocouple/RTD applications.
NKAS08-15: 1.5 m cable for pulse counter and frequency input module termination units.

Sourcing Hard-to-Find & Obsolete NKAS Parts

DriveKNMS maintains a dedicated inventory program for ABB NKAS series cables and associated S800 I/O termination accessories. As multiple NKAS variants have transitioned out of ABB's active production schedule, plant operators face extended lead times — often 16 to 52 weeks — through standard OEM channels. DriveKNMS sources verified surplus, new-old-stock (NOS), and factory-refurbished NKAS cables from decommissioned plant inventories, authorized distributor overstock, and controlled secondary market channels globally.

For facilities operating AC800M or legacy AC450/AC110 systems under long-term service agreements, DriveKNMS provides lifecycle extension support including: cross-reference verification against current ABB spare parts catalogs, compatibility confirmation for mixed-generation I/O rack configurations, and bulk procurement for planned plant turnarounds. Emergency same-day quotation is available for critical shutdown scenarios. All NKAS cables are shipped with full traceability documentation.

Quality Control for the NKAS Range

ABB NKAS cables, while passive interconnect components, are subject to failure modes including connector pin corrosion, shielding degradation, and insulation breakdown — particularly in units sourced from long-term warehouse storage or decommissioned plant environments. DriveKNMS applies a structured inspection protocol to all NKAS inventory prior to dispatch:

Connector integrity is verified under magnification for pin straightness, contact surface oxidation, and locking latch function. Cable shielding continuity is tested end-to-end using a calibrated low-resistance ohmmeter. Insulation resistance is measured at 500 VDC between signal conductors and shield to confirm dielectric integrity. Connector housing is inspected for mechanical damage, UV degradation, and correct strain relief seating. Each unit is individually bagged and labeled with inspection date, technician ID, and test result record. Cables destined for HART-enabled analog module applications (AI835, AO845) undergo additional signal path impedance verification to confirm compatibility with 4–20 mA HART communication overlays.