Holds the index number of the current field or alarm

THIS

THIS is useful to self-reference a field or alarm. For example to let a field self-increment, the following expression can be used:

f(THIS)+1

THIS is also useful in reverse math expressions to scale the field value to a suitable register value. This example scales a 0-10 mA value in the field to uA and offsets it to industry standard 4-20mA.

f(THIS)*1600+4000

Not applicable

Returns the index value of the current field or alarm.