SECS/GEM for Siemens S7 PLC Integration Guide
TransSECS supports direct integration of many PLCs including Siemens S7 PLCs - any Ethernet PLC - S7-300, S7-200 and S7-1500 series PLCs. You build the interface by configuring, rather than programming, although you might need a little scripting to validate remote commands.
TransSECS supports full GEM300 integration - E39, E40, E87, E94 as well as SECS (E4, E5, E37) and GEM (E30). It supports applications that do not use GEM and SECSI (serial) connections - very useful for older tools.
As with any TransSECS application, almost all GEM messages gem_tool_messages are handled directly by TransSECS. To build a complete application, all that is required is connect VIDs, CEIDs, and ALIDs. Remote commands and recipes (S7 messages) may also be required.
PLC connection
As with any other PLC, you create a connection to the PLC directly within the TransSECS editor.
once you've created the connection to the PLC you can add tags, based on registers, within the PLC node
For simplicity you can also import the tags from an Excel spreadsheet
as described here: Importing VIDs, CEIDs, and ALIDs into TransSECS
Connecting to VIDs, ALIDs and CEIDs
You connect from the tags to the SECS IDs. Just select the Device Name (eg CP243) and the tag name (eg GasFlow)
Whenever the host requests the value of the VID the correct value, as last read from the PLC, will be provided.
Similarly, ALIDs are configured so that any change will cause a SECS Alarm messages (S5F1) to be sent to the host with an indication that the alarm is set or cleared.
CEIDs are triggered by any change from zero to non-zero and can be reset either by TransSECS or the PLC.
Remote Commands
Handling Remote/Host Commands is described here: How to Handle Host Messages in TransSECS Devices
Recipe Management
TransSECS can support a wide range of recipe management options. The simplest is to use the CSV file support that is easily enabled in TransSECS TransSECS Recipe Management. There's really no limit to the sophistication of the solution, including using databases for recipe management TransSECS Devices Application Examples with Databases