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Advanced Logic
5.1.4 Using brackets
You can use brackets ( ) to group parts of the equation together. The system treats the part of
the equation in brackets as one unit.
For example, consider this equation:
**-**-**-ZS-000 AND **-**-**-ZS-001 OR **-**-**-ZS-002
This equation is true:
• If both **-**-**-ZS-000 and **-**-**-ZS-001 are pressed.
• If both **-**-**-ZS-000 and **-**-**-ZS-002 are pressed.
• If **-**-**-ZS-002 is pressed by itself.
In contrast, the following equation groups the last 2 inputs in brackets:
**-**-**-ZS-000 AND (**-**-**-ZS-001 OR **-**-**-ZS-002)
ANY Syntax: ANY n OF (input 1, input 2, ... input x) where n is a positive integer
An equation with ANY is true if any one of the following inputs are true.
For example, the equation ANY 1 OF (01-00-02-IN-003:A, 01-00-02-IN-004:A)
is true if any one of the inputs (01-00-02-IN-003 or 01-00-02-IN-004) is in alarm.
The following equation is true only if three of the 10 alarms are active.
ANY 3 OF (01-00-L2-SM-001:A , 01-00-L2-SM-002:A , 01-00-L2-SM-003:A ,
01-00-L2-SM-004:A , 01-00-L2-SM-005:A , 01-00-L2-SM-006:A , 01-00-L2-
SM-007:A , 01-00-L2-SM-008:A , 01-00-L2-SM-009:A , 01-00-L2-SM-010:A ,
01-00-L2-SM-011:A)
This equation can be used to release halon in a semiconductor clean room only
if three of the 10 verified alarms in the area are active.
EQU Syntax: input EQU Sys Def
EQU is an equal sign. An equation with EQU is true if the status of the input is
equal to the system defined value.
For example, the equation 01-00-02-IN-003:L EQU ALARM_LEVEL1 is true if
the level of the input (01-00-02-IN-003) equals alarm level 1.
As per UL 864 and UL 2572 only usage of an input's immediate TRUE or
FALSE value (without the application of a mask and a test for equality) is
permissible. That is, no combination of Device Status, the operator EQU or Sys
Def should be used.
Sys Def Sys Def is a system defined value. Commonly used system defined values are:
ALARM_LEVEL1 - alarm level 1
ALARM_LEVEL2 - alarm level 2
ALARM_LEVEL3 - alarm level 3
TIMER_EXPIRED - the specified timer has expired. See chapter 8.
TIMER_RUNNING - the specified timer is running. See chapter 8.
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