Specifications

Introduction
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Integrated Power Supply
The NIM’s built-in 24-to-5 VDC power supply provides logic power to the I/O
modules on the primary segment of the island bus. The power supply requires a
24 VDC external power source. It converts the 24 VDC to 5 V of logic power for the
island. Individual STB I/O modules in an island segment generally draw a logic bus
current of between 50 and 265 mA. (Consult the Advantys STB System Planning
and Installation Guide for current limitations at various operating temperatures.) If
the logic bus current drawn by the I/O modules totals more than 1.2 A, additional
STB power supplies need to be installed to support the load.
The NIM delivers the logic power signal to the primary segment only. Special
STB XBE 1300 beginning-of-segment (BOS) modules, located in the first slot of
each extension segment, have their own built-in power supplies, which provide logic
power to the STB I/O modules in the extension segments. Each BOS module that
you install requires 24 VDC from an external power supply.
Structural Overview
The following figure illustrates the multiple roles of the NIM. The figure provides a
network view and a physical representation of the island bus:
1 fieldbus master
2. external 24 VDC power supply, the source for logic power on the island
3. external device connected to the CFG port (a computer running the Advantys
Configuration Software or an HMI panel)
4. power distribution module (PDM): provides field power to the I/O modules
5. island node
6. island bus terminator plate
7. other nodes on the fieldbus network
8. fieldbus network terminator (if required)
PDM IO IO IO IO IO
PDM
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IO
IO
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