...
foo is the "name" of the meter and the three numbers are minimum, maximum, and threshold values for the meter. The default value is the minimum value (the value show shown when the suite begins). After the command "begin" it looks like: 
In the ecFlow job file you can then modify your task to change the meter while the job is running, e.g. like:
...
After the job has modified the meter a few times it looks like: 
And in the end, the meter looks like: 