Rockwell Automation 1746-HSCE,D17466.5 High-Speed Counter Module - Manual (Page 19)

1 Publication 1746-UM006B-EN-P - August 2005
Chapter
2
Module Operation
This chapter describes the basic operation of the module. Specific
programming information and individual memory maps for each
mode are contained in Chapter 4. This chapter contains overviews of:
•
module overview
•
input type selection
•
pulse and direction input
•
quadrature encoder input
•
up/down pulse input
•
the input pulse counter
•
the rate measurement calculation
•
output control
•
range, rate, and sequencer modes
Module Overview The main function of the module is to count the input pulses that
occur on the input channels A and B. Counter control and reset
control is provided through user configuration parameters. The
counter can be reset from any combination of the Z input, LS (limit
switch) input, and Soft Reset control bit.
In addition to the Accumulated Count, the module provides the Rate
Measurement indicating the pulse input frequency in Hz. The Rate
Measurement is determined by accumulating input pulses over a fixed
period of time. You set the rate period to best match your application
requirements.
The module’s four current sink (open collector) outputs can be
controlled from one of two sources:
•
the user program (in the Direct Outputs field)
•
the module:
– when the Accumulated Count is within user specified ranges
in Range Mode
– when the Accumulated Count passes specified preset values
in Sequencer Mode
– when the Rate Measurement is within user specified ranges in
Rate Mode