Siemens SIMATIC S7-1500 Manual page 17

Value status (Quality Information, QI)
The value status is always activated for the following modules:
● DQ 16x230VAC/2A ST QI
● DQ 16x230VAC/2A ST S QI
● DQ 16x230VAC/2A ST MSO
An additional bit is assigned to each channel for the value status. The bit for the value status
indicates if the output value specified by the user program is actually pending at the module
terminal (0 = value is incorrect).
Address space for configuration as 16-channel DQ 16x230VAC/2A ST QI
The following figure shows the assignment of the address space for the configuration as a
16-channel module with value status. 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 onto the module. "For example, AB a" stands for module start
address output byte a.
Figure 4-1
Digital output module DQ 16x230VAC/2A ST Relay (6ES7522-5HH00-0AB0)
Manual, 07/2017, A5E34934019-AC
Address space for configuration as 16-channel DQ 16x230VAC/2A ST QI with value
status
Parameters/address space
4.3 Address space
17