3 Product Description
X-AO 16 01
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HI 801 111 E Rev. 4.00
3.4 Structure
The module is equipped with 16 analog current outputs (0/4...20 mA) that are pairwise
electrically isolated from the supply voltage and the remaining channel pairs. The analog
current value is set with a D/A converter, measured by two independent, internal measuring
devices and functionally tested.
If two modules are redundantly connected, only 8 odd outputs (AO1, AO3...AO15) are
available. The even outputs (AO2, AO4...AO16) are not used.
The module automatically diagnosis open-circuits (OC) and can be evaluated in the user
program, see Chapter 4.3.
The safety-related 1oo2 processor system for the I/O module controls and monitors the I/O
level. The data and states of the I/O module are made available to the processor modules
via the redundant system bus. The system bus has a redundant structure for reasons of
availability. Redundancy is only ensured if both system bus modules are inserted in the
base plates and configured in SILworX.
3.4.1 Block
Diagram
The following block diagram illustrates the structure of the module.
System Busses
Safety-Related Processor System
Interface
Watchdog
Safety Switch for Group of 2
Power Supply (electrically isolated)
Block with D/A and A/D Converters
Electrical Isolation
Figure 2: Module's Block Diagram