NFDV561-P50

The Yokogawa NFDV561-P50 is a 64-channel isolated digital output module for the STARDOM FCN/FCJ autonomous controller platform. It provides 24 V DC transistor outputs in a current-sink configuration for switching external field loads. The module supports individual ON/OFF output control and configurable output fallback behavior, with an external field power supply required for output operation.

Functional Description

The NFDV561-P50 converts digital control commands from the FCN/FCJ controller into discrete electrical output signals. Its 64 output channels can control compatible DC field loads within the specified voltage and current limits.

The current-sink output arrangement switches the load current toward the common negative supply. Field devices must therefore be wired with the correct polarity and an appropriate external 24 V DC supply.

Output Characteristics

The module provides isolated 24 V DC digital outputs, with a maximum load current of 100 mA per channel. The maximum output ON voltage drop is 2 V DC, while the maximum leakage current in the OFF state is 0.1 mA.

Output isolation is specified between the output signals and the system, as well as between channel groups. The common negative side is arranged in groups of 16 channels, which should be considered when planning field wiring and grounding.

Output Status and Fallback Behavior

The module supports ON/OFF status output and configurable fallback actions. These settings determine how the output channels respond when the controller system enters a fallback condition:

• HOLD: Maintains the existing output states.
• OFF: Turns all output channels OFF.
• NO: Performs no fallback action.

The selected fallback behavior should match the process requirements and the field device's response to loss of normal control.

Technical Specifications

Parameter	Specification
Model	NFDV561-P50
Brand	Yokogawa
Product Type	Digital Output Module
Controller Platform	STARDOM FCN/FCJ
Number of Output Channels	64
Rated Applied Voltage	24 V DC
Load Voltage	24 V DC, 100 mA
Field Power Supply Range	20.4 to 26.4 V DC
Output Format	Current sink
Maximum Output ON Voltage	2 V DC
Maximum OFF-State Leakage Current	0.1 mA
Maximum Load Current	100 mA/channel at 26.4 V
Output Response Time	3 ms or less (status output)
Isolation Voltage	2,000 V AC for 1 minute (output signal to system); 500 V AC for 1 minute (between commons)
Maximum Current Consumption	780 mA at 5 V DC; 120 mA at 24 V DC field supply
Output Fallback	HOLD, OFF, NO
Fallback Detection Time	4 seconds
External Connection	MIL connector cable
Weight	0.3 kg

Specifications are based on Yokogawa General Specifications GS 34P02Q35-01E.

Model Suffix Identification

The NFDV561-P50 ordering code identifies the module's output configuration and hardware version.

Code	Description
NFDV561	64-channel, 24 V DC isolated digital output module
-P	Standard type
5	General-purpose type with no explosion protection
0	Basic type

The P50 configuration does not include the ISA Standard G3 option. It should not be confused with the P51 configuration, which includes that option.

Installation and Wiring Considerations

The module requires an external 24 V DC field power supply. Its MIL connector cable interface must be considered when selecting the associated field wiring and terminal arrangement.

When driving DC relays, Yokogawa specifies connecting a diode. The common negative connections are grouped in blocks of 16 channels, so field wiring should account for these electrical grouping arrangements.

The fallback selection applies commonly to all output channels rather than allowing separate HOLD, OFF, or NO settings for individual channels.

Frequently Asked Questions

Q: Is the NFDV561-P50 a sourcing or sinking digital output module?

A: It uses a current-sink output configuration. Field loads must be connected with the appropriate external 24 V DC supply and polarity.

Q: What is the difference between NFDV561-P50 and NFDV561-P51?

A: The P50 version is the general-purpose configuration without explosion protection or the ISA Standard G3 option. The P51 version includes the ISA Standard G3 option. These configurations should not be treated as interchangeable without checking the applicable installation requirements.

Q: What happens to the outputs when a fallback condition occurs?

A: The module supports three fallback selections: HOLD maintains existing output states, OFF resets all output channels, and NO performs no fallback action. The detection time is 4 seconds, and one fallback selection applies to all channels. 

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