when you write to your program
$TOL_TOUT := 10
why from exec and not from program? It works for me? If you can say? why you want change this variable?
As I said. If you want change that variable.. write program with this command and activate it
$TOL_TOUT := 2000
value will be 2000
To change the variable from teach pendant
From home screen
Display > VARS > System Var
Click on ... on Variabile field
Find and select $TOL_TOUT, and press OK, and OK again.
You will have a list showing $TOL_TOUT.
When You select it, button Attribute will be enabled
Press Attribute and Value...
And you can change the variable value manually.
But sometimes will be faster just write a line of code on some .cod file and run it, as Vladarius suggested.