Rockwell Automation 1440-SDM02-01RA XM-124 Standard Dynamic Measurement Module - Manuel (Page 81)

Rockwell Automation Publication 1440-UM001C-EN-P - May 2014 81
Configure the XM-124 Standard Dynamic Measurement Module Chapter 2
Alert Threshold (High)
The threshold value for the alert (alarm) condition.
Important: This parameter is the greater threshold value when
Condition is set to ‘Inside Range’ or ‘Outside Range,’ the measurement
is a phase measurement (Configuration Utility), or the alarm type is a
vector alarm (EDS file). Same measurement unit as Output Data Unit
selection for the specified channel except when
measurement/alarm type is phase (vector).
Phase Measurements/Vector Alarm Type
Requirements:
• The Alert Low, Danger Low, Alert High, and
Danger High must define contiguous sections
within the set of possible phase values
(0…360 degrees).
• If you were to plot the thresholds on a clock
face (illustration below) with phase increasing
in the clockwise direction, then set the
following:
– Alert Low must be clockwise from or equal
to Danger Low.
– Alert High must be clockwise from Alert
Low.
– Danger High must be clockwise from or
equal to Alert High.
Danger Threshold (High) The threshold value for the danger (shutdown) condition.
Important: This parameter is the greater threshold value when
Condition is set to ‘Inside Range’ or ‘Outside Range,’ the
measurement is a phase measurement (Configuration Utility), or the
alarm type is a vector alarm (EDS file).
Alert Threshold (Low) The lesser threshold value for the alert (alarm) condition.
Important: This parameter is not used when Condition is set to
‘Greater Than’ or ‘Less Than.’
Danger Threshold (Low) The lesser threshold value for the danger (shutdown) condition.
Important: This parameter is not used when Condition is set to
‘Greater Than’ or ‘Less Than.’
Hysteresis The amount that the measured value must fall (below the threshold)
before the alarm condition is cleared. For example, Alert Threshold =
120 and Hysteresis = 2. The alarm (alert) activates when the
measured value is 120 and does not clear until the measured value is
118.
Important: The Alert and Danger Thresholds use the same hysteresis
value.
Important: For the Outside Range condition, the hysteresis value must
be less than Alert Threshold (High) – Alert Threshold (Low). Same measurement unit as Output Data Unit
selection for the specified channel.
Detection Delay Enter the length of time for which the Alarm Condition must persist
before the alarm is signaled.
Applying delays may reduce nuisance alarms caused by external noise
and/or transient vibration events.
IMPORTANT: Delays may also be applied as part of the Relay
definition. Delays there are associated with the Relay’s Activation
Logic, and only begin once any Alarm condition is signaled.
Consequently, applying delays to both the Alarm and Relay results in
a total delay time, prior to relay actuation, that is the sum of the
alarm and relay delay times.
Enter a value between 0 and 65.5 seconds.
Start-up Period The length of time that the Threshold Multiplier is applied to the
thresholds. The start-up period begins when the setpoint multiplier
switch is reopened (push button disengaged or toggle switch flipped
to off). Enter a value from 0…1092 minutes, adjustable
in increments of 0.1 minutes.
Table 7 - Alarm Parameters
Parameter Name Description Values/Comments