Using a Script to "Multiplex" Boolean Tags in Siemens Portal

After spending some time working with multiplexed tags in Siemens Portal, I found that I was unable to set boolean values through a multiplexed tag. Instead of using a multiplexed tag, a simple script can help achieve the same function. The function of the script is to take the input parameters and set the proper boolean tag based on those parameters.

Example: Controlling Multiple Motors with One Pop-up

In this example, multiple motors need to be controlled from an HMI. Without a script, each motor would need a separate, but identical, motor pop-up to turn on and off the motor. However, with a script, all motors can use the same pop-up, reducing the number of total screens and simplifying future screen updates.

1. Upon selecting a motor from the HMI, an integer (motor index) is set depending on the motor selected.

2. On the motor control panel (set up using a pop-up screen), there are two buttons: one to turn the motor on, and one to turn the motor off. 

3. For each button, call the script (MotorOnOff). In this case, the On button passes in iMotorIndex and bOn = 1. The Off button passes in iMotorIndex and bOn = 0.

4. Reading the motor index and the button pressed, the script can write to the proper boolean tag.

With this workaround, a tag can be set for each motor without having to use a separate pop-up for each one. It will greatly help keep the total number of screens to a minimum and simplify future updates. 

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