Allen-Bradley 1404-M4, Руководство пользователя

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Publication 1404-UM001D-EN-E - October 2004
Advanced Features 8-3
Block Number
The block number and the total number of data reads required to read
an entire capture depend on the communications option and the
capture type . See Table 8.1. The block number range is 1 to the
number of Data reads required listed in the table.
Capture Type
The properties associated with the capture type options are listed in
Table 8.1. You may select a capture type that best suits your
application requirements. A higher sample rate provides a more
accurate representation of the waveform when higher-order
harmonics and transients are present. Higher data resolution provides
more accuracy of each data point. Capture type 5 combines low
sampling rate and low resolution, but captures almost 7 seconds of
waveform at 60 Hz.
Read-Back Mode
The data client uses the indexed read method to read oscillogram
capture data. The readback mode options are:
•
Auto-increment all channels: successive reads of Table A.40
increment through all remaining blocks of the current channel,
increment through all remaining channels and wrap back to the
original channel.
•
Auto-increment current channel: successive reads of the results
table will increment through all remaining blocks of the current
channel only.
Table 8.1 Capture Type Properties
Capture
Type Sampling
Rate Data
Resolution Samples per
Cycle at 60 / 50
Hz Total Cycles per
Channel at 60 / 50
Hz Capture
Duration
(seconds) Data Reads Required
DeviceNet Other Comms
0 5.4 kHz 13-bit
w/sign 90 / 108 51.1 / 42.6 0.85 230 92
1 2.7 kHz 45 / 54 102.2 / 85.2 1.70
2 1.35 kHz 22.5 / 27 204.4 / 170.3 3.40
3 5.4 kHz 7-bit
w/sign
90 / 108 102.2 / 85.2 1.70 460 184
4 2.7 kHz 45 / 54 204.4 / 170.3 3.40
5 1.35 kHz 22.5 / 27 408.8 / 340.7 6.81
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