Future Design MCT-CM, Руководство пользователя

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MCT-CM
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NOTE: The low and high alarm set point fields are shown for Absolute, Deviation & %Out alarm types.
Although both set point fields are shown, only the high SP is used for
‘high’ alarms, low for all ‘low’
alarms and both fields are used for Absolute, Deviation & %Out
‘both’ alarm types.
The Low set point defines the input value that will trigger a low side alarm. It must be lower than the alarm high
set point.
The
High set point defines the input value that will trigger a high side alarm. It must be higher than the alarm
low set point.
The
Differential (often referred to as alarm hysteresis) defines how far the input must return into the normal
operating range before the alarm can be cleared.
The alarm on delay time,
Delay (seconds) , can be used to delay the activation of the alarm. If the input exceeds
the alarm setting, but then re-enters the normal operating mode before the alarm delay time expires, the alarm
will not be activated. The allowable time setting is from 0
– 32,760 seconds. A value of zero (0) disables the
alarm delay and the alarm will activate immediately when the input exceeds the alarm settings.
The
Start Delay (seconds) works in conjunction with the alarm start delay mode selection. If the alarm start
delay is enabled, the start delay time can be used to set the maximum length of time the alarm can be inhibited.
For example, if a process is started, and the start delay is enabled, what happens if the process never reaches