1-6
IM 04P03B01-01E
For the procedure to set the functions, see section 1.6, “Function Setup Guide.”
1.2
Alarms
This function generates an alarm when the measured data meets a certain condition.
The alarm status is displayed on the screen while recording the alarm occurrence/
release on the chart paper.
Also, alarm output relays can be used to output contact signals when alarms occur (/A1,
/A2, and /A3 options).
Alarm Types
Number of Alarm Point Marks
Up to four alarms can be set for each channel.
Alarm Conditions
The following four conditions are available: The alphanumeric character or symbol inside
the parentheses is used on the recorder to denote each alarm.
• High Limit Alarm (H/
)
An alarm occurs when the input value exceeds the alarm value.
• Low Limit Alarm (L/
)
An alarm occurs when the input value falls below the alarm value.
Alarm
value
Alarm release
Measured value
Alarm occurrence
High limit alarm
Low limit alarm
Measured
value
Alarm release
Alarm value
Alarm occurrence
• Difference High Limit Alarm (h/
)*
An alarm occurs when the difference in the input values of two channels is greater
than or equal to the specified value.
• Difference Low Limit Alarm (l/
)*
An alarm occurs when the difference in the input values of two channels is less than
or equal to the specified value.
*
Can be specified on channels set to delta computation.
Alarm Hysteresis
Hysteresis can be specified to the values for activating and releasing the alarm. The
hysteresis applies only to high limit alarm (H) and low limit alarm (L). The hysteresis
width can be set in the range of 0.0% (OFF) to 1.0% of the recording span in 0.1 steps.
The setting applies to all high limit alarms and low limit alarms. By default, the hysteresis
width is set to 0.5%.
Alarm
value
Alarm release
Measured value
Alarm occurrence
High limit alarm
Low limit alarm
Measured
value
Alarm release
Hysteresis
(1% or less)
Alarm value
Alarm occurrence
<Related Topics>
Setting alarms: Section 2.2
Setting the alarm hysteresis: Section 4.1