Siemens S7-1500 Manual page 17

Address space for configuration as 16-channel DQ 16x230VAC/1A ST
The figure below shows the address space allocation for the configuration as 16-channel
module. You can freely assign the start address for the module. The addresses of the
channels are derived from the start address.
The letters "a to b" are printed on the module; "QB a", for example, stands for module start
address output byte a.
Figure 4-1
Address space for configuration as 2 x 8-channel DQ 16x230VAC/1A ST S
For the configuration as a 2 x 8-channel module, the channels of the module are divided into
two submodules. The submodules can be assigned to different IO controllers when the
module is used in a shared device.
The number of I/O controllers depends on the interface module being used. Please observe
the information in the manual for the particular interface module.
Unlike the 1 x 16-channel module configuration, each of the two submodules has a freely
assignable start address.
Figure 4-2
Note
Substitute value behavior in shared device operation with 2 x 8-channel configuration
If the system is in shared device mode and one of the associated IO controllers goes into
STOP or fails due to, for example, a communication failure, all submodules of the output
module follow the configured substitute value behavior (e.g. switch off).
This means that even when only one IO controller fails, the other IO controllers associated
with the shared device no longer control the assigned submodule of the output module.
Digital output module DQ 16x230VAC/1A ST Triac (6ES7522-5FH00-0AB0)
Manual, 09/2016, A5E34934069-AB
Address space for configuration as 16-channel DQ 16x230VAC/1A ST
Address space for configuration as 2 x 8-channel DQ 16x230VAC/1A ST S
Parameters/address space
4.3 Address space
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