Neles Automation A413135 AOU4 Analog Output Module

Technical Dossier

Product Details And Specifications

Neles Automation A413135 Series: Comprehensive Module Range and Technical Overview

The Neles Automation A413135 series represents a family of analog and digital I/O modules engineered for process automation environments in heavy industry. Deployed extensively across chemical processing plants, oil refineries, pulp and paper mills, and nuclear utility facilities, these modules form the backbone of distributed control system (DCS) architectures where signal integrity and long-term field reliability are non-negotiable. Neles Automation (formerly part of Metso Automation's valve and field device division) designed the A413135 platform to interface directly with positioner feedback loops, transmitter inputs, and actuator control outputs — making it a critical component in any facility running Neles ND800, NDX, or compatible valve controller infrastructure. The installed base of this series spans multiple continents, with particularly high concentrations in Scandinavian petrochemical facilities and Southeast Asian refinery expansions from the 1990s through the 2010s.

The Evolution of A413135 Architecture

The A413135 platform was developed during the late 1980s and matured through the 1990s as Neles Controls (later Neles Automation, then absorbed into Metso Automation) expanded its DCS and field device portfolio. Early revisions of the A413135 used parallel backplane communication with fixed-address slot assignment, limiting hot-swap capability. Mid-generation revisions introduced improved EMI shielding and extended the operating temperature range to accommodate outdoor cabinet installations in tropical climates. Later hardware revisions added conformal coating as standard, addressing corrosion failures reported in offshore platform deployments.

By the mid-2000s, the A413135 series entered a maintenance phase as Metso transitioned customers toward the Neles ND9000 and later Valmet-branded intelligent positioner platforms. However, the installed base remained substantial enough that Metso continued to supply spare modules through authorized channels until approximately 2015–2018, depending on the specific sub-model. Post-EOL, procurement of A413135 modules has shifted entirely to specialist aftermarket suppliers. Compatibility with legacy backplanes means direct substitution is not always possible with modern equivalents, making original-hardware sourcing the preferred maintenance strategy for facilities not yet scheduled for full DCS migration.

A413135 Full Catalog & Functionalities (SKU List)

The following SKUs represent verified models within the Neles Automation A413135 series and associated compatible modules. Each entry reflects a distinct functional role within the DCS I/O architecture:

A413135 AOU4: 4-channel analog output module, 4–20 mA, for valve positioner and actuator control loops.
A413135 AIN8: 8-channel analog input module, 4–20 mA / 1–5 V selectable, transmitter interface.
A413135 AIN4: 4-channel analog input module, high-resolution 16-bit ADC, for precision measurement loops.
A413135 DIN16: 16-channel digital input module, 24 VDC, dry contact and wet contact compatible.
A413135 DIN32: 32-channel digital input module, high-density I/O for status monitoring applications.
A413135 DOU16: 16-channel digital output module, 24 VDC sourcing, relay-driven field device control.
A413135 DOU8R: 8-channel relay output module, SPDT contacts, rated for 250 VAC / 2 A resistive loads.
A413135 RTD8: 8-channel RTD input module, supports PT100 / PT1000 / Ni100 sensor types.
A413135 TC8: 8-channel thermocouple input module, supports J, K, T, E, R, S, B type thermocouples.
A413135 PUL4: 4-channel pulse/frequency input module, for flow meter and encoder signal conditioning.
A413135 COM1: Serial communication adapter module, RS-232 / RS-485 dual-mode, Modbus RTU support.
A413135 COM2: PROFIBUS DP communication module, slave mode, for integration with third-party DCS hosts.
A413135 CPU1: Local controller CPU module, executes ladder and function block programs, 256 KB program memory.
A413135 PSU24: 24 VDC backplane power supply module, 5 A continuous, with short-circuit and over-voltage protection.
A413135 PSU48: 48 VDC redundant power supply module, for high-availability cabinet configurations.
A413135 BPX8: 8-slot backplane expansion unit, passive bus, supports mixed I/O module population.
A413135 BPX16: 16-slot backplane expansion unit, for high-channel-count marshalling cabinet installations.

Sourcing Hard-to-Find & Obsolete A413135 Parts

DriveKNMS maintains a dedicated inventory program for end-of-life Neles Automation modules, including the full A413135 range. As Metso Automation formally discontinued factory support for this series, facilities operating legacy DCS infrastructure face a constrained supply window. DriveKNMS sources A413135 modules through decommissioned plant asset recovery, authorized surplus channels, and direct procurement from facilities undergoing DCS migration projects.

All units are catalogued by hardware revision, firmware version where applicable, and physical condition grade (Grade A: unused surplus; Grade B: tested pull with full function verification; Grade C: cosmetic wear, full electrical function). For facilities requiring long-term maintenance agreements covering the A413135 platform, DriveKNMS offers consignment stock arrangements and priority reservation programs. Customers are advised to consolidate multi-line procurement requests into a single BOM submission to optimize lead time and shipping consolidation.

Quality Control for the A413135 Range

Each A413135 module processed by DriveKNMS undergoes a structured inspection and functional test protocol before dispatch. The procedure addresses the specific failure modes documented for this series, including backplane connector pin wear, analog output drift caused by aging DAC reference circuits, and digital I/O optocoupler degradation from extended field service.

Test stages include: visual inspection of PCB, connector, and housing integrity; powered-on self-test with backplane simulator; channel-by-channel signal verification against factory tolerance specifications (±0.1% full scale for analog channels); isolation resistance measurement between signal commons and chassis ground; and thermal cycling for units sourced from high-ambient-temperature installations. Modules that fail any stage are either repaired to specification by qualified technicians or quarantined and not offered for resale. Test records are retained and available upon request for quality-critical procurement processes.