Alarm Functions; Upper Limit Input Value Alarm; Lower Limit Input Value Alarm - Mitsubishi Electric MELSEC FX Series User Manual

FX -4LC User's Manual
3U
7.2

Alarm Functions

The alarm functions issue an alarm when the measured value (PV) or deviation [Measured value (PV) - Set
value (SV)] reaches the alarm set value.
The alarm status can be checked in the status of bits for alarms 1 to 4 of the event buffer memory.
For settings of alarm functions, refer to the following.
Caution
• In cascade control, the alarm waiting operation is disabled on the slave channel side when the set value
(SV) is changed.
• When the setting change ratio limiter is set to any value other than "0", the alarm waiting operation is
disabled when the set value (SV) is changed.
7.2.1

Upper limit input value alarm

When the measured value (PV) is more than the alarm set value, an alarm is issued.
Measured value (PV)
Alarm set value
Alarm status
7.2.2

Lower limit input value alarm

When the measured value (PV) is less than the alarm set value, an alarm is issued.
Measured value (PV)
Alarm set value
Alarm status
→ For details on the event, refer to Subsection 8.2.2.
→ For details on the measured value (PV), refer to Subsection 8.2.3.
→ For details on the set value (SV), refer to Subsection 8.2.15.
→ For details on the alarm setting value, refer to Subsection 8.2.16.
→ For details on the alarm mode setting, refer to Subsection 8.2.53.
Measured value (PV)
Measured value (PV)
Time
Non-alarm status
Alarm status
Time
Non-alarm status
Alarm status
7 Alarm
7.2 Alarm Functions
1
2
3
4
5
6
7
8
9
10
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