Yokogawa PW484-51 Power Supply Module

The Yokogawa PW484-51, also cataloged as the PW484-51 Power Supply Module, operates as a dedicated hardware component for stable 24 V DC power distribution within Field Control Units (FCU), FIO node units, and optical ESB bus repeater architectures.

Hardware Specifications

Process Control and DCS Instrumentation Characteristics

• 4-20 mA HART loop protocol: The module provides isolated DC power to field instrumentation loops, ensuring that voltage fluctuations do not inject noise into HART-based diagnostic data streams.
• FOUNDATION Fieldbus / Profibus PA connectivity: The unit serves as the primary power source for fieldbus segments, maintaining the tight voltage tolerances required for deterministic communication across digital networks.
• Channel-to-channel isolation: The power output stage is galvanically isolated from the primary power source, preventing common-mode noise and ground loops from affecting sensitive DCS processors and I/O modules.
• Cold junction compensation (CJC): While serving as a power component, the module is engineered to operate within strict thermal profiles to ensure that heat dissipation does not affect the CJC accuracy of adjacent temperature input modules.

Frequently Asked Questions

Q: How is the dual-redundant power configuration achieved?

A: Dual redundancy is implemented by installing two identical PW484-51 modules in the designated base plate slots (e.g., A2BE1D/A2BE2D). The system automatically manages load sharing and failover between the modules.

Q: Is the PW484-51 compatible with both AC and DC input racks?

A: The PW484 model specifically handles 24 V DC inputs. For AC-powered racks, the corresponding PW481 or PW482 variants must be used, ensuring the hardware matches the site power infrastructure.

Field Installation Guidelines

• Mounting: Seat the module into the compatible base plate (A2BE1D/A2BE2D). Ensure the exclusive connector is fully seated and the locking mechanism is secured to maintain a stable electrical path to the backplane.
• Grounding: Bond the base plate chassis to the cabinet’s instrument earth bus. A low-impedance ground is mandatory to maintain stable reference potentials and to provide effective surge protection for the system.
• Wiring: Terminate the 24 V DC input supply at the rack power terminals. Keep input power cabling physically separated from sensitive communication and analog signal wiring by at least 150 mm to eliminate inductive interference.