METSO A413111 Potentiometer Feedback Board / Sensor Unit
The Metso (now Neles/Valmet) A413111 is a high-precision Potentiometer Unit or Feedback Sensor Module specifically designed for use within the Neles ND9000 series intelligent valve positioners. It serves as the “eyes” of the positioner, providing continuous electronic feedback of the valve’s actual position.
1. Product Description
The A413111 is a specialized electronic assembly consisting of a high-resolution potentiometer mounted on a PCB.
It is installed inside the positioner housing and coupled to the actuator shaft. Its primary function is to convert the mechanical rotation (or linear movement) of the valve into a precise electrical resistance signal, which the positioner’s microprocessor uses to ensure the valve reaches the exact desired setpoint.
This component is engineered for extreme reliability, as any failure in this unit would result in the “loss of feedback,” causing the valve to fail-safe or hunt for position.
2. Technical Parameters
| Parameter | Specification |
| Component Type | Potentiometer Feedback Board / Sensor Unit |
| Resistance Range | Typically 5kΩ or 10kΩ (Optimized for ND9000 logic) |
| Linearity | < ± 0.5% of total stroke |
| Rotational Angle | Up to 90° (Rotary) / Compatible with linear stroke adapters |
| Operating Voltage | Low voltage (supplied by the ND9000 internal circuit) |
| Connection | Multi-pin ribbon cable or plug-in header |
| Operating Life | > 2 million cycles (High-durability conductive plastic) |
| Protection | Conformal coating for moisture and vibration resistance |
A413111
3. Product Advantages & Features
High Precision: Provides micro-degree resolution, enabling the ND9000 to maintain extremely tight control loops.
Rugged Construction: Designed to withstand the constant “dithering” (small movements) required for precise throttle control without wearing out.
Temperature Stability: Minimal resistance drift across the standard industrial temperature range (-40°C to +85°C).
Direct Integration: Part of the Metso “Modular Design” philosophy, allowing for easy field replacement without replacing the entire positioner.
Vibration Dampening: The PCB and mounting are designed to handle the high-frequency vibrations found in heavy-duty piping systems.
4. Application Cases
Control Valve Loops: Essential for any modulating valve application (e.g., steam flow control, pressure regulation).
Critical Process Control: Used in pulp and paper mills for exact liquor and pulp flow management.
Chemical Batching: Ensuring exact valve opening percentages for chemical dosing and mixing.
Energy Sector: Position feedback for turbine bypass valves or feedwater control valves.
5. Related & Other Models in the Series
The A413111 is often associated with specific versions of the ND9000 and ND7000 positioners.
ND9100 / ND9200: The intelligent positioners that typically house the A413111 module.
A413112 / A413113: Variations of the feedback board, sometimes including additional limit switches or different connector types.
Neles RE series: Rotary actuators that provide the mechanical motion for this sensor.
Service Kits: Often included in ND9000 Maintenance Kits along with seals and filters.