Red Lion LEGEND - Manual (Page 11)

OVERFLOW INDICATION
The unit flashes the word “OVERFLOW” (or assigned mnemonic) in the
appropriate display when an overflow condition occurs. An overflow occurs if the
capacity of the display (6-digits Process & Batch, 8-digits Total) is exceeded or if the
internal count capacity (9-digits Process, 7-digits Batch, 11-digits Total) is
exceeded. The use of an extremely small Scale Multiplier and Scale Factor value can
cause the internal count capacity to overflow before the displayed value overflows.
For example, if a Scale Factor of 0.0001 and a Scale Multiplier of 0.001 is
used, for every 10,000,000 count edges received, the display increments by 1.
Before the display reaches 215, the internal counter overflows. When the
capacity of the display is exceeded, the count value is maintained and is valid. If
the internal count capacity is exceeded, the count value is no longer valid.
Use of a Scale Factor larger than “1” can cause the displayed Process or Total
value to overflow before 999,999 counts are accumulated. The use of a Rate
Scale Factor, Scale Multiplier, and Rate Conversion Factor larger than “1” can
cause the rate display to be in an overflow condition.
The counters should not be allowed to operate in an overflow condition. As
soon as, or before the counters overflow, the information should be recorded and
the counters reset.
PEAK & VALLEY
The Peak and Valley registers record the lowest (Valley) and the highest
(Peak) readings of the rate input signal. These values are viewed in the indication
display loop and are updated automatically. A User Input can be programmed to
reset the values to the current rate value individually or by sending the proper
command via the serial communication port. The Peak and Valley values are
NOT retained when power to the unit is removed.
NORMAL OPERATING MODE
In the normal operating mode, the up, down, left, and right arrow keys are used
to scroll through the main display loop. In the main display loop, the four
indication displays, scale factors, and program mode modules are viewed, as
shown at right. In the indication display loop, the up and down arrow keys are used
to scroll to each display. The indication displays are referenced as 1 (0 PRC/0
CPS), 2 (PEAK), 3 (VALLEY), and 4 (PROCESS), which are the factory default
settings. The indication displays can be programmed to show other parameters and
automatically scroll (See Program Displays Module). The last indication display
that was viewed at power down, is the one viewed on power up.
The Presets and Counter Load values are accessed from any of the indication
displays or from the programming loop. The Count, Rate, and Total scale factors
are accessed from the Scale Factors display or when in the programming loop
from the Program Scaling module. In the Program Mode display, the operator
enters the programming loop to access all parameters to configure the unit.
Shown below is the Main Display Loop.
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