METSO A413240A Printed Circuit Board Assembly
The Metso (now Neles/Valmet) A413240A is a specialized Circuit Board assembly, specifically the Main Electronics Module for the Neles ND9000 series intelligent valve positioners.
It is the upgraded or specific revision of the control board used to manage high-precision valve modulation and diagnostics.
1. Product Description
The A413240A acts as the central processing unit for the ND9000 digital positioner.
It is responsible for the “intelligence” of the valve, performing real-time PID calculations, managing HART communication, and monitoring the health of the valve-actuator assembly.
This specific revision (often denoted by the ‘A’ suffix) is engineered for high reliability in extreme industrial environments, featuring advanced noise filtering and power management to ensure stable performance even on long cable runs or weak 4-20 mA loops.
2. Technical Parameters (Technical Data)
| Parameter | Specification |
| Component Type | Main Controller PCBA (Printed Circuit Board Assembly) |
| Communication | 4-20 mA with HART 5, 6, or 7 support |
| Input Impedance | Equivalent to approx. 470 $\Omega$ at 20 mA |
| Minimum Current | 3.6 mA for basic operation; 3.8 mA for communication |
| Microprocessor | High-speed, low-power RISC controller |
| Ambient Temperature | -40°C to +85°C (-40°F to +185°F) |
| Humidity Limits | 0–95% RH (Non-condensing) |
| Conformal Coating | Standard (protects against moisture and corrosive gases) |
3. Product Advantages & Key Features
High-Speed Control Loop: Capable of processing feedback signals at millisecond intervals to ensure zero steady-state error.
Advanced Diagnostics: Supports “Online Valve Signature” and “Performance Trend” monitoring, allowing users to see friction changes or air leaks without stopping the process.
Low Voltage Drop: Designed to operate on a very low “Lift-off voltage,” making it compatible with older DCS systems or those with high-resistance barriers.
A413240A
Modular Hardware: Allows for the easy addition of optional modules like internal Limit Switches or 4-20 mA Position Transmitters (AO).
EMI/RFI Protection: High immunity to electromagnetic interference, ensuring the valve doesn’t “jump” when handheld radios are used nearby.
A413240A
4. Application Cases
Critical Control Loops: Used in oil refineries for precise pressure and temperature control in cracking units.
Remote Diagnostics: In large-scale chemical plants where technicians use HART multiplexers to check valve health from the control room.
Pulp & Paper: Managing “Stock Flow” valves where high vibration and humidity are constant factors.
Safety Instrumented Systems (SIS): Serving as the control electronics for ValvGuard (PST) systems to ensure emergency shutdown valves are functional.
5. Related & Other Models in the Series
The A413240A is often used interchangeably or alongside these related components:
ND9100 / ND9200: The primary positioner housings that utilize this board.
A413111: The feedback potentiometer unit that connects to this board via a ribbon cable.
A413120: The pneumatic relay (pre-amplifier) that this board controls.
A413245: The Foundation Fieldbus (FF) or Profibus version of the main board.
Service Kit (Revision specific): Often sold as part of a “Major Spare Parts Kit” for the ND9000 series.