===== This (field/alarm number) =====

==== THIS ====

Holds the index number of the current field or alarm

=== Description ===

<code>THIS</code>

THIS is useful to self-reference a field or alarm. For example to let a field self-increment, the following expression can be used: 
<code>f(THIS)+1</code>

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.

<code>f(THIS)*1600+4000</code> 

=== Parameters ===

Not applicable

=== Return value ===

Returns the index value of the current field or alarm.