Description

Yokogawa AFF50D-H41201 Duplexed Field Control Unit

The Yokogawa AFF50D-H41201, also cataloged as the AFF50D Duplexed Field Control Unit, operates as a dedicated hardware component for real-time control logic execution within CENTUM distributed control systems. It provides dual-redundant processing and communication pathways for uninterrupted signal computation and field interface management.

Hardware Specifications

Parameter	Specification
ModelBrand	Yokogawa AFF50D-H41201
Origin	Japan
Weight	Approx. 8 kg
Dimensions	19-inch rack-mountable
OperatingTemp	0 to 50 degC
PowerConsumption	220-240 VAC: 230 VA / 24 VDC: 5.5 A
Processor	VR5432, 133 MHz
MainMemory	32 MB
MemoryProtection	Battery backup, up to 72 hours
BatteryRechargeTime	Minimum 48 hours
FCUStatusOutput	2 terminals (NC, C), 30 V DC max 0.3 A
CommunicationInterface	Dual-redundant V net; dual ESB bus
PowerSupply	100-120 VAC 50/60 Hz, 220-240 VAC 50/60 Hz, 24 VDC

Process Control Characteristics

The AFF50D-H41201 supports channel-to-channel isolation to prevent signal interference across process loops. It maintains compatibility with 4-20 mA HART loop protocols and supports FOUNDATION Fieldbus and PROFIBUS PA connectivity for direct device-level data acquisition. Cold junction compensation (CJC) is implemented for precise thermocouple measurement under fluctuating ambient conditions.

Frequently Asked Questions

Q: What happens to the FCU outputs during a processor fault?
A: The status contacts (NC, C) open immediately upon any FCU failure to signal downstream alarms.

Q: Can the AFF50D-H41201 memory battery be replaced without shutting down the unit?
A: No. Battery replacement requires unit shutdown to preserve memory integrity.

Q: Are the V net interfaces hot-swappable?
A: No. Interface modules must be powered down before removal or installation.

Field Installation Guidelines

• Install the unit in a 19-inch standard rack with sufficient ventilation for heat dissipation.
• Ensure all power and communication cables are routed separately to avoid cross-talk or electromagnetic interference.
• Ground all metal chassis points according to industrial earthing standards.
• Avoid exposure to direct moisture and corrosive aerosols despite the G3 conformal coating.
• Maintain at least 50 mm spacing around the FCU for airflow and service access.

Specifications

• Brand: Yokogawa

Advantages

• High reliability in industrial environments
• Supports continuous operation
• Compatible with major PLC/DCS systems