Flowserve MX/QX Profibus DP/PA Field Unit - Manual (Page 8)

PB DPV1 / PA Field Unit Installation and Maintenance FCD LMENIM2336-03 – 12/12
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The devices used to create a segment are Repeaters for copper networks, Optical Link Modules for
glass or plastic-coated glass fiber-optic networks, and Optical Bus Terminals for plastic fiber-optic
networks. Each of these devices provides either electrical or optical isolation between segments.
The MX/QX PB field unit fits in the actuator in the sealed electrical housing compartment. There
are two different communication board options for the MX/QX PB field unit: MX/QX PB DP, which
supports PROFIBUS DP (Decentralized Periphery) RS-485 physical layer and MX/QX PB PA, which
supports PROFIBUS PA (Process Automation) IEC 1158 physical layer. The MX/QX PB DP field unit is
available with Flying and System Redundancy.
PROFIBUS DP ensures high-speed data transmission of user data, and is designed especially for
communication between a master host station and distributed devices at the field level.
PROFIBUS PA uses the expanded PROFIBUS DP protocol for data transmission and implements the
PA profile that specifies the characteristics of the field device. This transmission technique ensures
intrinsic safety and powers the field devices over the bus. PROFIBUS PA is designed for high-speed
and reliable communications, with the ability to link sensors and actuators to a common fieldbus line,
even in potentially explosive areas.
PROFIBUS PA devices can be integrated into PROFIBUS DP networks using segment couplers.
The adjustments to the MX/QX PB settings may be made locally at the actuator and over the
PROFIBUS network using a DPV1 network configuration tool.
A typical MX/QX PB DP system is shown in Figure 1.1 in a Master/Slave Configuration, Figure 1.1a
shows a typical PROFIBUS DP network with redundancy option in a single master configuration,
Figure 1.1b shows a typical PROFIBUS DP network with redundancy option in a dual master
configuration, and Figure 1.2 shows a typical MX/QX PB PA system.
Figure 1.1 – Typical PROFIBUS DP Network with DCS or PLC as the Host System
Actuator Actuator Actuator
PB PB PB PB
Actuator
PROFIBUS DP-V1
Interface
Control Highway
Distributed Control
System (Host)
T Terminator
T
Terminator
PROFIBUS DP Network
Power for the fieldbus devices and cable shield
grounding are discussed in Sections 2.4 and 2.5.