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V2
AC500 Hardware
1-32 System
data
AC500 / Issued: 05.2007
I/O-Bus
General
The synchronized serial I/O-Bus connects the I/O expansion modules with the AC500 CPU or with the
S500 FBP Interface Module.
The I/O-Bus provides the following signals:
•
Supply voltage of 3.3 V DC for feeding the electronic interface components
•
3 data lines for the synchronized serial data exchange
•
several control signals
With its fast data transmission, the I/O-Bus obtains very low reaction times. Up to 7 I/O expansion
modules can be connected to a AC500 CPU or an FBP Interface Module.
If both of the following conditions are fulfilled,
max. 10 I/O expansion modules can be connected to
the I/O-Bus of the CPU:
- PS501 as of version V1.2
- CPUs as of firmware V1.2.0
General data:
Supply voltage, signal level
3.3 V DC ± 10 %
Max. supply current
30 mA per expansion module
Max. number of I/O expansion modules (slaves
on the I/O-Bus)
7 with the S500 FBP Interface Module with max.
4 analog modules (with up to 16 channels each),
7 with the AC500 CPU (digital or analog),
10 with the AC500 CPU (PS501 as of V1.2 with
CPUs with firmware as of V1.2.0)
Type of the data interface
synchronized serial data exchange
Bus data transmission speed
1.8 Mb/s
Minimum bus cycle time
500 µs ¹)
Electrical isolation
no isolation between the modules, but isolation
against the process supply voltage and the I/O
terminals
Protection against electrostatic discharge (ESD)
with an internal varistor
Max. bus length
1 m
¹) Minimum bus cycle time: This value is valid for all module combinations (from 1 to 7 expansion
modules)
Wiring (bus connection)
Bus connection
left-side and right-side connection from module to module via a 10-
pole HE plug (male at the left side, female at the right side)
Mechanical connection
established by the Terminal Units
Max. bus length
1 m
Number of user data, bus cycle time and data security
See details before
