Siemens SIMATIC S7-1200

Web server
12.7 User-defined Web pages
S7-1200 Programmable controller
1044 System Manual, V4.2, 09/2016, A5E02486680-AK
12.7.2.1
Reading variables
User-defined Web pages can read variables (PLC tags) and data block tags from the CPU,
provided that you have configured the tags to be accessible from an HMI.
Syntax
:=<Varname>:
Parameters
<Varname> The variable to be read, which can be a PLC tag name from your STEP 7 program,
a data block tag, I/O, or addressable memory. For memory or I/O addresses or
alias names (Page 1055), do not use quotation marks around the tag name. For
PLC tags, use double quotation marks around the tag name. For data block tags,
en
close the block name only in double quotation marks. The tag name is outside of
the quotation marks. Note that you use the data block name and not a data block
number.
Examples
:="Conveyor_speed"::="My_Data_Block".flag1:
:=I0.0:
:=MW100:
Example reading an aliased variable
<!-- AWP_Out_Variable Name='flag1' Use='"My_Data_Block".flag1' -->
:=flag1:
Note
Defining alias names for PLC tags and data block tags is described in the topic
Using an
alias for a variab
le reference (Page 1049).
If a tag name or data block name includes special characters, you must use additional
quotation marks or escape characters as described in the topic Handling tag names that
contain special characters (Page 1055).