Product Overview

The Yokogawa NFAP135-S00 S2 is a high-performance, 8-channel isolated pulse input module designed for the STARDOM and CENTUM VP Distributed Control Systems. This specialized interface is engineered to capture high-speed frequency signals from field-side devices such as turbine flowmeters, rotary encoders, and displacement sensors. With an expansive input frequency range of up to 10 kHz and the ability to detect pulse widths as narrow as 40 μs, the NFAP135-S00 S2 provides the precision required for high-speed manufacturing and process monitoring.

Operating within the FIO (Field Interface Orbus) architecture, this module utilizes galvanic isolation to separate field signals from internal system logic, effectively eliminating ground loops and noise interference. Its rapid 2ms data refresh cycle ensures that the control system receives near-instantaneous updates, which is vital for applications involving turbine speed monitoring, production totalizing, and rotational velocity calculations.

Technical Specifications

• Manufacturer: Yokogawa

• Model Number: NFAP135-S00 S2

• Module Type: Pulse Input Module

• Number of Channels: 8 channels, isolated

• Input Frequency Range: 0 to 10 kHz

• Minimum Pulse Width: 40 μs

• Data Refresh Cycle: 2 ms

• Input Resistance: 68 kΩ (at pull-up)

• Selectable Shunt Resistance: OFF, 200 Ω, 500 Ω, 1000 Ω

• Transmitter Power Supply: Selectable 12 V DC or 24 V DC

• Isolation Withstand Voltage: 1.5 kV AC

• Operating Temperature: -20°C to +70°C

• Dimensions: 3.2 cm x 10.6 cm x 13.0 cm

• Weight: 0.25 kg

• Origin: Japan

Key Technical Characteristics

• High-Speed Detection Capabilities: Optimized for precision frequency measurement, the module accurately captures pulses up to 10,000 Hz, making it suitable for high-speed turbine and motor monitoring.

• Flexible Input Conditioning: Features user-selectable shunt resistors and dual-voltage pull-up options (12V/24V), allowing the module to interface seamlessly with a wide variety of sensor types, including dry contacts and open-collector outputs.

• Signal Integrity Enhancement: Equipped with a configurable digital filter function to eliminate contact chattering and signal bounce, ensuring stable and reliable pulse counting in noisy industrial environments.

• Integrated Sensor Powering: Provides an onboard transmitter power supply, reducing the need for external power distribution components and simplifying field wiring for 2-wire and 3-wire sensors.

• Rapid Control Response: The 2ms refresh interval allows for highly deterministic control loops, facilitating immediate action by the controller based on changes in process frequency or pulse counts.

• Rugged Safety Isolation: Includes 1.5 kV AC isolation between input channels and the system bus, safeguarding the main control station against field-side electrical surges and transients.