Specification; Overview - Pepperl+Fuchs HD2 Series Manual

Compact Fieldbus Power Hub,Generic Interface

Specification

2 Specification
2.1

Overview

The FieldConnex
segments in redundant mode according to IEC 61158-2.
The compact Power Hub is a high-performance power supply for FOUNDATION Fieldbus H1,
consisting of a motherboard with sockets for plug-in modules. In redundant versions, the Power
Hub features 2 power supply modules per segment. For each 4 segments, a socket for 1
diagnostic module is available.
The Power Hub is designed for use with fieldbus systems in accordance with IEC 61158-2.
This standard specifies how power and communication are transmitted sharing a shielded
twisted pair cable. Communication between field devices and a host system is established by
modulating the data signal onto the power stream. For this, Manchester Bus Powered (MBP)
transmission technology is used.
All FieldConnex
features are passive impedance generation, well-balanced circuitry, and low power dissipation.
All active electronic components are located in the plug-in modules. Each module holds the
electronic components for 1 segment and 2 modules operate in redundant configuration. When
an exchange becomes necessary, only few electronic components need to be exchanged
when compared to block configurations for power supplies. Modules can be exchanged while
the system is energized without tools, thus ensuring high system availability.
Impedance generation prevents the data signal from being short-circuited by the low internal
resistance of the power supply. This impedance generation is designed with passive
components such as inductances and resistors with long durability.
A fully balanced circuit and segment design is important for undisturbed fieldbus operation. An
external disturbance through EMI impacts both leads of the shielded twisted pair cable
symmetrically. The data signal is thus undisturbed. Low power dissipation allows highest
packing density inside the cabinet and a long service life.
When applied to fieldbus in hazardous areas, the Power Hub feeds segments following the
high-power trunk concept for explosion protection. High power level on the trunk line is fed to
the field device via couplers such as FieldBarriers or Segment Protectors. The Power Hub
powers segments installed as non-sparking (Ex nA).
FieldBarriers enable live maintenance in Zone 0/1 as outputs are classified Ex ia. Thus, power
limitations of intrinsically safe explosion protection are overcome, enabling maximum cable
lengths and highest number of devices in any hazardous area.
2 plug-in advanced diagnostic modules for fieldbus are available. These modules monitor the
physical layer online and in real time, enabling detection of degradation and faults during
operation. Measurement data and alarms are transmitted to the control room. They bring
visibility to the fieldbus physical layer, so it can be treated as an active component in plant asset
management systems. On this basis, operators can decide on proactive measures to avoid
unwanted situations while the plant is running smoothly.
The following table summarizes the main features and benefits of the Power Hub:
Features
Lowest heat dissipation of less than 2 W per
segment under full load condition.
Exchange of modules while the system is
energized and load share between power
modules.
Full balance of electric circuitry with high
isolation against RF and in-band interference.
High-integrity passive power conditioners.
compact Power Hub is intended to power 8 FOUNDATION Fieldbus H1
®
compact Power Hubs feature superior design elements. The main design
®
User benefit
Long service life. Very high packing density
and reduced cooling requirements.
Increased segment availability.
High resistance to external disturbance such
as EMI.
Long service life.
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