Siemens SITRANS WM300 MFA, Operating Instructions Manual

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Parameter assignment
6.7 Differential speed detection
SITRANS WM300 MFA
Operating Instructions, 08/2018, A5E45090709-AA
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DSD Calibration
The DSD must be calibrated so that each input has a full scale reading that is proportional to
the maximum operating speed of the machinery. The maximum input frequency for each
input is 5000 Hz. In DSD mode, the two calibrated inputs are compared to each other and if
the differential is greater than the set point, it will go into alarm.
For example:
1 Hz on a 1000 Hz full scale is equal to 0.1% speed change.
1 Hz on a 100 Hz full scale is equal to 1% speed change.
1 Hz on a 10 Hz full scale is equal to a 10% speed change.
Note
The input resolution is 1 Hz. Depending on the Input frequency calibration, this 1 Hz value
will represent a different percentage of speed change.
● P040: Enabled or Disabled
6.7.2 Maximum frequency setpoint (P041 - P042)
Probe C maximum frequency (P041) for comparison to probe A. Enter the maximum
frequency between pulses for probe C. Input I5 is the second frequency input (motion failure
sensor) with respect to Input I3, applied to the same mechanical equipment being monitored.
Probe D maximum frequency (P042) for comparison to probe B. Enter the maximum
frequency between pulses for probe D. Input I6 is the second frequency input (motion failure
sensor) with respect to Input I4, applied to the same mechanical equipment being monitored.
● For example:
I3 maximum Hz = 60 Hz
I5 maximum Hz = 30 Hz
Alarm setpoint = 10 %