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Expressions
Within the configuration of an ezeio, mathematical expressions are used to produce a value/result for “Fields”, “Alarms” and “Conditions”. This powerful tool can produce mathematical and logical results using multiple constants and/or variables from the available resources on an ezeio. Expressions can be as simple as the constant “1” to indicate True/ON or as complex as necessary.
Simple example
Purpose - Show the value of register 8 on device 2:
r(2,8)
Complex example
Purpose - Low oil pressure siren (during work schedule)
Logic - If oil pressure is less than 25 and RPM is greater than 600 and hour is between 06:00 and 17:00
Enter the following in the “Field” relate to an output register
(r(3,4)<25 && r(3,3)>600 && hour()>6 && hour()<17
Functions & Operators
Many of the valid functions and operators will be familiar to you, such as +, -, >, <, and =. Others come from advanced mathematics and logic, such as sin(), tan(), ||, and &&. Another category relates specifically to eze System terms and functions, such as Day() and K2F.