Table of Contents

Alarm Trigger for Real Variables (v1.1)

Full Name

Lib.Mervis.v1_1.real_to_alrtrig

Required Project References

Description

Auxiliary block used for generating an alarm from a real variable.

Usage in ST

program test
    var
        alrTrig: lib.mervis.v1_1.real_to_alrtrig;
    end_var

    alrTrig();
end_program

Inputs

Name Data TypeRetainRequired to ConnectMeaning
Input bool No Yes Input value
Priority AlarmPriorityType No No Alarm class
LowLimit real No No Lower allowable value
HighLimit real No No Upper allowable value
Hysteresis real No No Hysteresis around limit values
Delay time No No Alarm delay
TriggerTypeRealAlarmTriggerType No No Type of monitored event

Outputs

Name Data TypeMeaning
Alarm AlarmTriggerOutput

Detailed Function Description

The block generates an alarm if the Input is outside the defined range. The alarm is activated when the condition specified by the TriggerType parameter is met.

Condition Condition for Activation Condition for Deactivation
LowAndHighInput < LowLimit or Input > HighLimitInput > LowLimit + Hysteresis and Input < HighLimit - Hysteresis
Low Input < LowLimit Input > LowLimit + Hysteresis
High Input > HighLimit Input < HighLimit - Hysteresis

If a delay is set, the condition for activation must be met for at least this defined period.

Versions