Mobility, Intelligent Traffic Systems
Sopers Lane, Poole, Dorset, BH17 7ER
Security
classification Unrestricted
Page
27 of 92
Version
3
Status
Issued
Last Editor
Alan Doyle
Date
05-Oct-2017
Document Name
Stratos Outstation General and ICM Handbook Document No. 667/HB/52250/000
Copyright © Siemens plc 2014. All Rights Reserved. Mobility and Logistics is a division of Siemens Plc
4.2 GSPI
The Generic Serial Peripheral Interface (GSPI) Bus is used within the system to connect
serial communications and power to the main intelligent components of the system. In the
Stratos Outstation the power source on the GSPI bus is the PSU board, but the
communications master is the CPU board.
The CPU board provides two RJ45 connectors to downstream peripherals both which are
on the same communications Bus. On each peripheral there are also two RJ45
connectors with “IN” and “OUT” connections allowing connection in from the master and
out to the next peripheral in the chain.
The PSU board, when powered from the Mains PSU module in normal powered mode
provides power on both its upstream and downstream GSPI RJ45 connectors. When the
Mains power fails and the unit enters battery backup mode the power is cut by software to
peripherals on the downstream (“OUT”) side in order to preserve battery capacity.
For GSPI peripherals that have a general purpose I/O capability (e.g. the PSU board and
the IO board) their IO is mapped into the CPU board in 8 bit ports for example: gspi
1
.in.0.
For details on the I/O mapping process refer to the UTMC OTU Handbook
667/HB/46000/004. For the IO port mapping for specific peripherals, then please see their
respective section in this document.
4.3 Power
Supply
The Stratos Outstation can be powered from a standard AC mains supply or an external
DC supply.
The following supply voltages may be used:
Nominal Voltage
Minimum
Voltage
Maximum
Voltage
Frequency
Power Break Support
Time
120V, 230V
90V
264V
50/60Hz +/-4% 50ms under max load*
24V External DC
(refer to
Engineering
Poole for more
information)
10V
28V
DC
Depends on external
supply and backup
battery configuration.
* If a backup battery is fitted, then support time will be 1 minute (software controlled).
See section 3.6
Table 4 – Power Supply Voltages
4.4
The CPU Board
The CPU board holds the configuration and performs the function of configuration, control
and management. The CPU runs the Linux operating system and specific applications for
functions such as MOVA7 and UTMC OTU.