Rockwell Automation 1440-SDM02-01RA XM-124 Standard Dynamic Measurement Module - Manuel (Page 151)

Rockwell Automation Publication 1440-UM001C-EN-P - May 2014 151
CIP Objects Appendix B
Speed Measurement
Object (Class ID 325
H
)
The Speed Measurement Object models a speed measurement of a tachometer
signal.
Class Attributes
The Speed Measurement Object provides no class attributes.
Instance Attributes
Services
(1) Attributes can only be set while the device is in Program mode. See the description of the Device Mode Object for more information.
Table 74 - Speed Measurement Object Instance Attributes
Attr ID
Access Rule
Name Data Type Description Semantics
3 Get Speed Value REAL The measured speed value. CPM
4 Get Status BOOL Indicates if a fault or alarm has
occurred. 0 = Operating without alarms or faults.
1 = Alarm or fault condition exists. The
Speed Value attribute may not represent
the actual field value.
5 Get Maximum Speed REAL The maximum (peak) measured
speed value since the most recent
reset. CPM
12 Get/Set Time Constant UINT The time constant value used for
exponential averaging of the
Speed Value (a low pass filter/
output smoothing filter). Milliseconds
13 Get Acceleration REAL The rate of change of the Speed
Value. CPM/min
14 Get/Set Measurement
Response USINT Determines how quickly the Speed
measurement responds to change.
For example, setting this attribute
to 1 indicates a settling time of
220 ms. This means that the speed
is averaged over a quarter second,
and the reported value reaches
90% of the new steady state value
about 220 ms after the change in
machine speed. See table below.
Meas.
Response Settling
Time Time
Constant
0 2640 ms 1200 ms
1 220 ms 100 ms
2 22 ms 10 ms
Table 75 - Speed Measurement Object Services
Service Code
Class/Instance Usage Name Description
05
h
Instance Reset Clears Maximum (Peak) speed to 0.
0E
h
Instance Get_Attribute_Single Returns a single attribute.
10
h
Instance Set_Attribute_Single Sets a single attribute.
(1)