Description
Product Overview
The Yokogawa NFPW444 is a 24 VDC-input power supply module designed for Yokogawa STARDOM FCN controller systems. It converts the incoming DC supply into a regulated 5.1 VDC output used by the controller and associated I/O electronics. The module is rated for an output current of 7.8 A, making it a key power component in the controller’s modular architecture. Its role is to maintain the electrical supply required by the system’s processor and installed modules rather than to process field measurement signals directly.
The Yokogawa NFPW444 also provides a 24 VDC analog field-power function for compatible field circuits. This is relevant in installations using analog I/O modules that require a separate field supply for connected transmitters. The module includes SYS-POWER and FLD-POWER indicators, along with checking terminals for monitoring the system and field-power rails. Yokogawa documentation lists a maximum input current of 3.3 A and a rated 5.1 VDC output current of 7.8 A.
In maintenance applications, the Yokogawa NFPW444 should be selected according to the installed controller family, base module, power arrangement, and required suffix configuration. The NFPW444 is used in FCN-related platforms, but the exact system configuration determines whether a single or duplex arrangement is appropriate. Procurement teams should verify the complete model code, explosion-protection option, and G3 coating option where applicable. A replacement should also be tested under the expected system load, with both the 5.1 VDC system output and the 24 VDC field-power function checked before the controller is returned to service.
Product Introduction
Power instability in a controller rack can cause CPU resets, I/O communication interruptions, or loss of field-device supply. The NFPW444 addresses the rack-level power requirement by converting a 24 VDC cabinet supply into the 5.1 VDC rail used by the FCN system.
During replacement, checking only the input voltage is insufficient. The 5.1 VDC output, field-power function, module status indicators, and installed redundancy arrangement should all be verified under operating load.
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Model | NFPW444 |
| Manufacturer | Yokogawa |
| Product Type | DC Power Supply Module |
| System Family | STARDOM FCN / FCJ |
| Rated Input Voltage | 24 VDC |
| Input Voltage Range | 21.6–31.2 VDC |
| Maximum Input Current | 3.3 A |
| Input Fuse Rating | 6.3 A |
| Maximum Inrush Current | 20 A |
| Main Output Voltage | 5.1 VDC |
| Rated Output Current | 7.8 A |
| Analog Field Power | 24 VDC |
| Field-Power Current | Up to 4 A |
| Withstand Voltage | 500 VAC |
| Power-Failure Insensitivity | 2 ms |
| Status Indicators | SYS-POWER, FLD-POWER |
| Check Terminals | +5 V-CHK, +24 V-CHK, GND |
| Weight | Approximately 0.6 kg |
| Installation | Compatible FCN controller base |
| Redundancy | Supported in compatible configurations |
| Operating Temperature | 0°C to 55°C when used with in the referenced system documentation |
| Protection Options | Suffix-dependent; verify complete order code |
NFPW444
Major Features and Advantages
24 VDC input for industrial control cabinets
The accepts a nominal 24 VDC supply, with a documented operating input range of 21.6–31.2 VDC. This makes it suitable for control cabinets using a regulated 24 VDC distribution system. Input voltage should be measured at the module terminals under load, not only at the cabinet power supply.
Regulated 5.1 VDC system output
The module supplies the 5.1 VDC rail required by the controller and associated electronics. Its rated output current is 7.8 A. When diagnosing a power-related fault, check the output voltage under the actual rack load and inspect the module’s status indicators.
Integrated analog field-power function
The module provides a 24 VDC field-power function with a documented 4 A rating. This supports compatible analog field circuits, including installations where transmitter power is required. The field-power wiring must follow the applicable base-module and I/O documentation.
Duplex power configuration
The can be used in compatible redundant power arrangements. This allows system designers to configure a second power module to support availability requirements. Confirm the base-module configuration, load allocation, and wiring before replacing one unit in a redundant pair.
Front-panel diagnostic indicators
SYS-POWER indicates the status of the 5.1 VDC system output, while FLD-POWER indicates the 24 VDC field-power condition. The checking terminals provide additional access for voltage verification during commissioning and maintenance.
Order-code options
Yokogawa documentation identifies suffix options including standard versions without explosion protection, explosion-protected versions, basic types, and ISA Standard G3 options. The suffix must match the installation’s environmental and certification requirements.
Related Products
These models belong to the wider Yokogawa STARDOM and FCN power and controller ecosystem. They are not automatically interchangeable.
- NFPW441 – FCN power supply module with 100–120 VAC input.
- NFPW442 – FCN power supply module with 220–240 VAC input.
- NFPW426 – DC-input power supply module for specified FCN-RTU configurations.
- NFBU050 – Short base module used in FCN configurations.
- NFBU200 – Long base module supporting larger FCN configurations.
- NFCP050 – FCN-RTU CPU module.
- NFAI135 – Analog input module for compatible FCN systems.
- NFDV551 – Digital output module used in FCN configurations.
Frequently Asked Questions
Q1: What is the Yokogawa used for?
It supplies power to compatible Yokogawa STARDOM FCN controller systems. It converts a 24 VDC input into a regulated 5.1 VDC system output and provides a 24 VDC analog field-power function.
Q2: Can the operate from a 24 VDC power supply with voltage fluctuations?
The documented input range is 21.6–31.2 VDC. The actual cabinet supply should remain within this range under normal and transient operating conditions. Check voltage at the module input terminals.
Q3: Can I hot-swap the ?
Do not assume online replacement is permitted in every installation. Although compatible systems support duplex power configurations, the exact base module and controller documentation must be checked before removing a module under power. Follow the site’s approved isolation and maintenance procedure.
Q4: Does the support firmware v3.1?
The is a hardware power supply module, not a firmware-controlled CPU or communication module. System software and hardware compatibility should be verified against the installed FCN controller documentation rather than assigning a firmware version directly to the power supply.
Q5: What is the difference between and NFPW441?
The principal difference is the input power source. accepts 24 VDC, while NFPW441 accepts 100–120 VAC. They are different electrical configurations and should not be substituted without checking the base-module and power-system design.
Q6: How do I check whether an is operating correctly?
Check the 24 VDC input, SYS-POWER indicator, FLD-POWER indicator, and the corresponding checking terminals. Measure the 5.1 VDC output under load and verify the field-power circuit where used. A lit indicator alone does not establish that the module can sustain the required rack load.
Q7: What should I verify when ordering an replacement?
Confirm the complete model suffix, input voltage, explosion-protection requirement, G3 coating requirement, and controller base compatibility. Also request the module’s condition report and functional test results.
Procurement and Quality Inspection Notes
Before accepting a replacement , check:
- Complete model and suffix code.
- 24 VDC input compatibility.
- 5.1 VDC output under load.
- 24 VDC field-power operation.
- SYS-POWER and FLD-POWER indicators.
- Connector and terminal condition.
- Compatibility with the installed FCN base module.
- Redundancy configuration and load requirements.
- Explosion-protection and G3 options where required.
- Functional test documentation and warranty terms.
Important: Do not select an solely because its basic model number matches. The suffix determines important configuration and environmental options. Confirm the complete nameplate code before installation.
