METSO A413665 Active Control Unit (ACU) / Processor Module
The METSO A413665 is a critical electronic module within the Valmet / Metso DNA (formerly Metso Automation) system.
It is specifically categorized as an ACU (Active Control Unit) or a high-level Processor/Communication Board used to manage sophisticated industrial automation tasks.
1. Product Description
The METSO A413665 serves as a core processing component in the Metso DNA distributed control system.
It is designed to execute complex control algorithms and manage high-speed data exchange between field devices and the operator interface.
Type: Active Control Unit (ACU) / Processor Module.
Manufacturer: Metso Automation (now Valmet).
Role: Acts as the primary logic controller or communication hub for a specific segment of the industrial process.
Form Factor: Industrial-grade PCB mounted within a ruggedized housing for rack installation.
2. Technical Data Sheet (Specifications)
| Parameter | Specification |
| Model Number | A413665 |
| Product Type | ACU (Active Control Unit) / Processor |
| Weight | Approx. 1.8 kg (including housing) |
| Operating Voltage | 24V DC (System Integrated) |
| Connectivity | Ethernet (TCP/IP), High-speed Serial, and System Bus |
| Processor Type | High-performance embedded industrial processor |
| Indicators | Multicolor LED Status (Run, Fail, Power, Communication) |
| Cooling | Passive convection / Cabinet airflow |
| Standards | CE, UL certified (standard for industrial automation) |
3. Related Models
The A413665 is often found in systems alongside these common components:
A413654 (NCU2): Often works in tandem with Network Control Units for wider system connectivity.
A413110 (TIU6): Used for terminal interface and I/O routing.
Neles ND9000: Intelligent valve controllers that communicate with the A413665.
Metso I/O Modules: Analog (AI/AO) and Digital (DI/DO) cards that report directly to this control unit.

A413665
4. Application Cases
Mining & Metal Refining: Used in the control loops of large-scale grinding mills and flotation cells where precise timing is essential.
Pulp & Paper Processing: Managing the high-speed “Wet End” control and “Dry End” quality monitoring in Valmet paper machines.
Chemical & Petrochemical: Controlling safety-critical sequences and maintaining pressure/temperature stability in reactor vessels.
Power Plant Automation: Managing burner control systems and steam turbine monitoring in combined-cycle power plants.
5. Product Features and Advantages
High Processing Speed: Capable of handling hundreds of PID loops and logic sequences simultaneously with minimal latency.
Industrial Hardening: Specifically designed to resist electromagnetic interference (EMI) and vibration commonly found in heavy industrial plants.
Hot-Swap Capability: In redundant configurations, these modules can often be replaced without shutting down the entire control process.
Advanced Diagnostics: Provides deep-level system logs that can be accessed remotely for predictive maintenance.
Scalability: Allows for the expansion of the Metso DNA system by simply adding more units to the network.
6. Other Models in the Same Series
The Metso/Valmet A413xxx series includes several specialized boards:
A413660 / A413662: Alternative processor or memory variants within the ACU family.
A413000 Series: Various power supply and bus-coupling modules.
DCN / ACN Series: Active Control Nodes that represent the modern evolution of the A413 series architecture.