FOXBORO FBM243/243b Intelligent Device Modules

FOXBORO FBM243/243b Intelligent Device Modules

DESCRIPTION

The FBM243, FoxCom Dual Baud Rate, Intelligent Device Module contains eight individual channels. The FBM243b, FoxCom Dual Baud Rate, Intelligent Device Module contains four individual input channels and four 0 to 20 mA analog output channels. Each input provides internal isolated power and digital communication capabilities to a Foxboro Intelligent Field Device. Each channel communicates over a single twisted pair of wires and each channel of the FBM243/243b is channel isolated.

The modules also allow the use of an external power supply to power the Intelligent Field Device. (The use of an external power supply common to two or more loops needs the use of a cable balun module to maintain digital communication line balance). The baud rate is determined by the configuration of the field device connected to each channel, independently of the other channels. The modules provide bidirectional digital communication at 4800 baud rate between the Intelligent Field Device and the system redundant Fieldbus, or provides bidirectional digital communication at 600 baud rate between the field device and the modules while allowing a simultaneous 4 to 20 mA analog signal from the field device to an emergency shutdown system.

The FBM243/243b is an Intelligent Field Device host, enabling the system to receive digital messages from the field device in engineering units. Each message is received ten times per second at 4800 baud, and two times per second at 600 baud. Each message contains:

• Up to three measured variables in IEEE 32-bit floating-point format 

• Security information 

• Diagnostics 

• Message checking

Since communication is bidirectional, the system can display the output, transmitter temperature (°C and °F), and the results of continuous self-diagnostics. In addition, the following information can be displayed or reconfigured from a console, a Field Communicator, or PC-Based Configurator: 

• Output in engineering units 

• Fail-safe information 

• Tag number, name and location 

• Device name (letterbug) 

• Last calibration date 

• Two levels of upload/download capabilities

Features

• For the FBM243, 8 individual digital communication channels 

• For the FBM243b, 4 individual dual baud, FoxCom communication channels and four 0 to 20 mA analog output channels 

• Receives messages 10 times per second at 4800 baud, or 2 times per second at 600 baud, and contains: 

◦ Up to 3 measured variables in IEEE 

◦ 32-bit floating-point format 

◦ Security information 

◦ Diagnostics 

◦ Message checking 

• Allows use of an external power supply or the FBM243 internal isolated power to power the Intelligent Field Device 

• Digital communication capabilities to a Foxboro Intelligent Field Device over a single twisted pair of wires 

• Allows a simultaneous 4 to 20 mA analog signal from the field device to an emergency shutdown system 

• Termination Assemblies (TAs) for locally or remotely connecting field wiring to the FBM243 

• Termination Assemblies (TAs) for non-intrinsically safe or intrinsically safe applications

Standard Design

The FBM243/243b has a rugged extruded aluminum exterior for physical protection of the circuits. Enclosures specially designed for mounting of the FBMs provide various levels of environmental protection, up to harsh environments per ISA Standard S71.04.

Visual Indicators

Light-emitting diodes (LEDs) incorporated into the front of the module provide visual indication of the module operational status, and communication activity of the input channels.

Fieldbus Communication

The Fieldbus Communications Module (FCM) or the Field Control Processor (FCP) interfaces to the redundant 2 Mbps module Fieldbus used by the FBMs. The FBM243/243b accepts communication from either path (A or B) of the 2 Mbps Fieldbus. If one path is unsuccessful or is switched at the system level, the module continues communication over the active path.