Allen-Bradley FLEX I/O 1794-IP4, Руководство пользователя, Страница: 11 / 70

Chapter
1
Publication 1794-6.5.16 – September 1998
Read this chapter to familiarize yourself with the 1794–IP4 module.
For information on See page
How You Use the Pulse Counter Module . . 1–1
What the Pulse Counter Module Does . . . . 1–3
Input Capabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–4
How the Pulse Counter Operates . . . . . . . . . . . . . . . . . . . . . NO TAG
The 1794–IP4 module is an intelligent I/O module designed to
perform high speed pulse counting. The module provides:
•
4 pulse transmitter interfaces, each with 2 optocoupled inputs
Each input has + and – inputs for connection to transmitters with
complementary and noncomplementary signals.
The pulse inputs can accept frequencies up to 100KHz. The module
accepts and returns binary data.
The module’s primary use is accurate, high-speed counting of pulses
from flow meters or density meters. This includes quantity counting
and speed calculations.
The module has 2 16–bit up/down counters per channel. Each of the
4 interfaces can be individually configured for:
•
period time measurement using one 16–bit counter and
accumulating pulse counting using the other 16–bit counter.
•
period time measurement using a 32–bit counter.
An internal clock (1 or 10MHz) is used for period time
measurement.
The number of periods of the input signal to be measured is
selectable (1, 2, 4, 8, 16, 32, 64 and 128 periods).
The Pulse Counter has 4 identical pulse transmitter interfaces
(12–24V dc), each with 2 signal inputs (N and D). Each input has +
and – connections to the pulse transmitter.
What This Chapter
Contains
How You Use the
Pulse Counter Module
Allen-Bradley HMIs