Load timer value from HMI v350

[Jamie123]

Hello,

I am trying to load a timer with a value entered from the HMI.  As you can see I have linked the timer TD to an operand in the ladder.

The problem is when you enter the time value from the HMI it doesn't load this value into the timer in the ladder.

Could someone please help me work out how to do this.

Thanks in advance

 

[Joe Tauser]

The value shown on the ladder diagram will not be updated but the new preset will be there.  To test this, go online and click on the timer.  The new preset should be listed in the dialog box.

Note that if you download the ladder again, Visilogic will notice this and ask if you want to upload the PLC value.  If you don't click the PLC check box it will download the value you have on your saved program.

Joe T.

[Jamie123]

Thanks Joe. The values are in the preset as you said.

 

In order for the new preset value to take effect, does the PLC have to be restarted?

[Flex727]

It looks to me like you're confusing certain things. The Preset value you see in your ladder is set by you, the programmer, and will not change unless you check the appropriate box on download when the Preset value in the PLC is different.

The Preset value in the PLC will change when, like the above, you download the program and check the appropriate box. The PLC Preset value can also change in the PLC by keyboard entry, but the change will not be visible on the screen (if the Preset value is being displayed) until the timer is next reset, either by Reset coil or by timer expiration. If the timer is running when the Preset is changed, the new Preset will not take effect until expiration of the current cycle.

There is no need to restart the PLC for timer changes.