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X-VA-MT3809G-MT3810G-eng/541B182AAG/A/2022-10
Brooks Instrument
Installation Manual MT3809G & MT3810G
Section 3 Operation
other preferred high and low limits. The units of measure of the alarm
limits are the same units of measure as the process variable itself.
Computations: Totalization
Totalizers are available in both resettable and inventory options.
Resettable totalization is used for batching while inventory totalization
measures the total volume over time. Units of measure are set
independently for each of these options.
Pulse output: Pulse out scaler, pulse out width
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a variable frequency and therefore can pass information to many types
of external equipment such as batch controllers, automation systems
or provers. The output pulse width default is 1 millisec but may be user-
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high incoming frequency.
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level is below which the process is intended. Below this level, the totalizer
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accumulated by the totalizers.
Pulse output overrun alarm
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pulses may be delayed or queued. No loss of pulses will occur. The
totalizer output pulses will to be sent until the queue is empty. Under
these circumstances, an alarm message will be sent to the control station.
However, the alarm can be disabled if not required.
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Three additional parameters may be programmed for process and
diagnostic alarms to control functionality- enable, destination, and alarm
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depending on use of the alarm. For example, if output pulses are being
used it may be normal practice to delay (e.g. queue up) output pulses
because of a slow receiving end-device that requires a wide pulse-width.
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the pulse output overrun
alarm and not send an alarm when in fact pulse outputs are delayed by
choice. Some critical diagnostic alarms, such as database initialization,
can not be disabled or turned off. When an alarm occurs, it can be posted
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both or neither. Therefore the alarms may be managed according to
local operating practices and the need to notify upstream control/safety
systems.
An alarm may be posted at a designated destination only when the alarm
situation is occurring or posted until the alarm is acknowledged by the
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operator can see that there is an alarm as it is occurring (unlatched) or
even after the fact, in the case when the operator did not directly observe
the unit alarm (latched).
