Mobility, Intelligent Traffic Systems
Sopers Lane, Poole, Dorset, BH17 7ER
Security
classification Unrestricted
Page
43 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
4.8
The 48-16 I/O Board
The I/O board provides TR2523 compliant input and output functions for the system (48
inputs and 16 outputs). This board acts as a GSPI device to allow the CPU board to
communicate with it. This board is known as the 48-16 I/O Board to identify it against the
ST950 I/O boards.
Figure 11 – 48-16 I/O Board
The main functions of the I/O Board are:
•
48 inputs (for detectors, push buttons etc)
•
16 isolated changeover relay contact outputs
•
I/O connector is compatible with Gemini2 Bus/MOVA I/O board pinout
•
GSPI pass-through connection for daisy chaining of GSPI peripherals
•
Powered by the GSPI Connection
Inputs
The I/O board inputs are compliant to TR2523:2005 as follows:
•
Closed-Circuit is indicated when a resistance of 250 Ohms or less is present across the
input terminals.
•
Open-Circuit is indicated when a resistance of 100K Ohms or greater is present across
the input terminals.
•
The open-circuit voltage across the input terminals is typically less than 24V DC.
(Will track backup battery voltage during the backup period)
•
The short-circuit current is typically less than 2.5mA.
(Will be lower during backup period as the input voltage tracks the backup battery
voltage)
In practice, any resistance across the input terminals that results in a voltage of greater
than 7.5V across the input terminals will be read as Open-Circuit.
Any resistance across the input terminals that results in a voltage of less than 2.5V across
the input terminals will be read as Closed-Circuit.
