Yokogawa Standalone MW100 - Manual (Page 32)

1-18
IM MW100-01E
Upper Limit on Rate-of-Change/ Lower Limit on Rate-of-Change Alarm
The rate of change of the measured values is checked over the rate-of-change detection
interval. An alarm occurs if the rate of change of the measured value in the rising or
falling direction exceeds the specified value.
Change in the
measured value
T
Time
Interval
1
T 2
t 1 t 2
2 1
Amount of change in
the setting
T
Time
2
T 1
t 1 t 2
Computed value
Change in the
computed value
t –t
Interval
2 1 t –t
2 1 T –T
Upper limit on rate-of-change alarm Lower limit on rate-of-change alarm
Computed value
Amount of change in
the setting 1 T –T 2
Alarm Hold/Non-Hold
You can select whether, when factors resulting in output cease to exist, alarms are
cleared when the output factors are cleared, or alarms are held for their full duration (alarm
ACK*).
Output cause
occurrence
• When set to non-hold • When set to hold
ON
Alarm
OFF
Output cause
occurrence
ON
Alarm
Status lamp
ALARM
Monitor screen
alarm view
Status lamp
ALARM
Monitor screen
alarm view
OFF
Alarm ACK Alarm ACK
* By clicking the Alarm ACK button in the browser’s monitoring screen or by sending an
equivalent communication command.
Tag Strings
Tag strings can be set for each measurement and MATH channel.
You can select whether to display tag name or channel numbers on all channels.
Messages
Message strings set in advance are written to the monitor screen and message summary
per operations of the Event/Action function, communication commands, and buttons on
the browser.
Number of messages: 5 (1 to 5)
Free Message
When you enter a message in the browser’s monitor screen and press a button during
data acquisition or recording, the message is written to the monitor screen and message
summary.
If you switch the screen after inputting a message string without writing the message, the
input message string reverts to the string prior to the change.
Number of messages: 1 (Free)
1.3 Functions of the Main Module