NFSB100-S50/SBT01

The Yokogawa NFSB100-S50/SBT01 is an SB bus repeater module designed for FCN (Field Control Node) systems. It extends the SB bus communication path between connected segments using serial communication at 128 Mbps, with a maximum distance of 8 m per segment. This configuration includes an SB bus T-joint and supports duplex configuration and hot swapping.

Function and Communication

The NFSB100 repeats SB bus communication signals between connected bus segments. It supports a communication rate of 128 Mbps and a maximum segment distance of 8 m. These limits are relevant when planning the physical bus layout and determining the placement of repeaters.

Three front-panel LEDs provide operating status information:

• STATUS: Indicates hardware readiness.
• SND: Indicates transmission activity.
• RCV: Indicates reception activity.

The SND and RCV indicators help distinguish transmission and reception activity when checking the communication path.

Configuration and Ordering Code

The supplied ordering information identifies the following configuration elements:

Code	Specification
-S	Standard model
5	Without explosion protection
0	Basic type
/SBT01	Supplied with an SB bus T-joint

The complete ordering code NFSB100-S50/SBT01 therefore identifies the standard, non-explosion-protected basic model with an SB bus T-joint. The T-joint is part of the specified ordering configuration and should be considered when checking replacement requirements.

Electrical and Mechanical Specifications

Parameter	Specification
Model	NFSB100-S50/SBT01
Brand	Yokogawa
Product Type	SB Bus Repeat Module
Application	FCN
Transmission Method	Serial communication
Transmission Rate	128 Mbps
Maximum Transmission Distance	8 m per segment
Duplex Configuration	Possible
Hot-Swap	Possible
Power Supply Voltage	5 V DC +/-5%
Maximum Current Consumption	500 mA
Status Indicators	STATUS, SND, RCV
Weight	0.2 kg
Operating Temperature	0 to 55 deg C
Dimensions (W x H x D)	32.8 x 130 x 142.5 mm

Installation and System Configuration

The NFSB100 connects an FCN control unit to I/O extension units. For a duplex SB bus configuration, two repeat modules are required in each unit. Each module connects through a dedicated SB bus T-joint and cable.

The module has a specific base-module requirement: it is designed for the NFBU200 long base module. It cannot be installed on the N2BU051, NFBU050 short base module, or N2BU030 compact base module. This distinction should be checked before ordering a replacement or planning a system modification.

Yokogawa specifies a maximum of two extension units, or three units when the control unit is included. The 8 m transmission-distance limit applies to each SB bus segment rather than the total system cable length.

Frequently Asked Questions

Q: Does the NFSB100-S50/SBT01 support hot swapping?

A: Yes. Hot swapping is supported. However, this capability should not be confused with duplex operation, which requires two NFSB100 modules per unit.

Q: What is required for a duplex SB bus configuration?

A: Install two NFSB100 repeat modules in each unit using the applicable base-module arrangement, dedicated T-joints, and SB bus cables. The duplex configuration uses separate repeat modules for the two bus paths.

Q: Can the NFSB100-S50/SBT01 be installed on an NFBU050 base module?

A: No. The NFSB100 is specified for the NFBU200 long base module and is not compatible with the NFBU050 short or N2BU030 compact base modules.

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