Allen-Bradley 1747-OC Series, User Manual

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1747-UM001A-US-P - March 2000
A-6 Specifications
Calculating Scan Time
Add the rows in the following tables to calculate input and output scan
times. Fill in the shaded boxes with the correct values. All times are in
microseconds.
Estimate minimum input scan time
Estimate maximum input scan time
Discrete I/O Modules:
number of class 0 input words: x 48 =
Specialty I/O Modules (Class 1)
number of 1746-BAS modules (class 1):
number of 1746-NIO4V modules:
number of 1746-FIO4V modules:
number of 1746-NI4V modules: x 490 =
x 265 =
x 265 =
x 325 =
Specialty I/O (Class 3 and 4)
number of 1746-HSCE modules:
number of 1747-SN modules:
number of 1746-BAS modules (class 4): x 712 =
x 1185 =
x 650 =
Forced Input Overhead
number of class 0 input words:
number of specialty input words:
number of specialty I/O modules: x 6 =
x 9 =
x 30 =
Input Scan Overhead 36
Minimum Input Scan Time (total)
Minimum Input Scan Time
(from above table)
Maximum Specialty I/O Input Scan Time
number of class 1 specialty I/O modules:
number of class 3 and 4 specialty I/O modules: x 50 =
x 200 =
Maximum Input Scan Time (total)