Red Lion LEGEND - Manual (Page 20)

COUNT MODES (Cont’d)
QUAD X2 (QUADRATURE X2)
When two edge counting is used, the quadrature mode works the same as
with single edge counting when Input B is low. But when Input B is a high
level, counts at Input A are no longer ignored. Instead, the logic rules for Input
A are complemented, allowing both edges of Input A to be counted. This
doubles the effective resolution of the encoded input.
QUAD X4 (QUADRATURE X4)
This mode takes the quadrature mode, with two edge counting, one step
further. In quadrature times 4, both Input A and Input B serve as the count or
quadrature input, depending on their state. In one instance, Input A will serve
as the count input and Input B will serve as the quadrature input. In another
instance, Input A will be the quadrature input and Input B will be the count
input. This enables each edge, positive and negative going, of both inputs, 1
and 2, to be counted. This results in a resolution four times greater than in the
basic quadrature X1 mode. As in the other modes, Input A is also used for the
rate input.
ADD/SUB (TWO INPUT ANTI/COINCIDENCE ADD/SUBTRACT)
This mode effectively separates count pulses that may simultaneously
appear at the two inputs. The Legend unit processes the count pulses into a
string of time-separated pulses, so the internal counter will not lose any count
pulses. Input A serves as the add input (count increments) and Input B serves
as the subtract input (count decrements).
ADD/ADD (TWO INPUT ANTI/COINCIDENCE ADD/ADD)
This mode effectively sums count pulses that may simultaneously appear at
the two inputs. The Legend unit processes the count pulses into a string of
time-separated pulses so the internal counter will not lose any count pulses.
Input A serves as an add input (count increments) and Input B serves as an
additional add input (count increments).
PROCESS RESET ACTION
The Process count display can be reset to Zero, Preset 2, or to the Counter Load
value. The method of reset for the display can be automatic or by a user input. The
type of reset from a user input can be a Maintained or Momentary reset (Refer to
Program User Module for details). Automatic reset is covered in the next section.
Note: Response time for a manual reset is 10 msec maximum.
RESET TO ZERO
When reset, the Process Counter Display value will return to Zero.
RESET TO PRESET 2
When reset, the Process Counter Display value will return to the Preset 2
value. Output 2 triggers when count reaches zero. This mode is not
recommended for Boundary.
RESET TO COUNTER LOAD
When reset, the Process Counter Display value will return to the Counter
Load value.
Note: The counter load reset action should be programmed for only one count
display, either the process count or the batch count.
PROCESS AUTOMATIC RESET
The Automatic reset mode can be enabled or disabled. The Process Counter
display will automatically reset to the programmed reset action, when one of the
automatic reset modes is selected. A manual reset by a user input will cause the count
to reset regardless of the automatic reset mode. The following choices are available:
OUT1 (Reset at Beginning Of Output 1)
In this mode, the counter will reset when the count equals the preset 1 value.
Output 1 can be timed or latched.
OUT1END (Reset at End Of Timed Output 1)
In this mode, the counter will reset after output 1 has timed out.
OUT2 (Reset at Beginning Of Output 2)
In this mode, the counter will reset when the count equals the preset 2 value.
Output 2 can be timed or latched.
OUT2END (Reset at End Of Timed Output 2)
In this mode, the counter will reset after output 2 has timed out.
OUT1&2 (Reset at Beginning Of Output 1 or Output 2)
In this mode, the counter will reset, when the count equals either preset 1 or
preset 2 value. Outputs 1 and 2 can be Timed or Latched.
OUT1&2E (Reset at End Of Timed Output 1 or Output 2)
In this mode, the counter will reset, after output 1 or output 2 has timed out.
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