Siemens SIMATIC S7-1500 Manual page 17

Value status (Quality Information, QI)
The meaning of the value status depends on the submodule involved.
For the 1st submodule (=basic submodule), the value status 1 indicates that the output value
specified by the user program is actually output at the module terminal.
Possible causes for value status = 0:
● Value is incorrect, for example, because the supply voltage is missing.
● IO controller of the basic submodule is in STOP mode.
For the 2nd to 4th submodule (=MSO submodule), the value status 1 indicates that the
output value specified by the user program is actually output at the module terminal.
Possible causes for value status = 0:
● Value is incorrect, for example, because the supply voltage is missing.
● IO controller of the basic submodule is in STOP mode.
● The basic submodule is not yet configured.
The figure below shows the assignment of the address space for submodules 1 and 2.
Figure 4-3
Digital output module DQ 16x24VDC/0.5A BA (6ES7522-1BH10-0AA0)
Manual, 09/2016, A5E32364017-AC
Address space for configuration as 1 x 16-channel DQ 16x24VDC/0.5A BA MSO with
value status
Address space
4.1 Address space
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