4
7. COUNTER B SCALE FACTOR
(b SCLFAC) INP A-b = dUAL cnt
The scale factor is a prescaler, therefore changing the scale factor value does
not change the existing internal count, and only affects the incoming pulse
count. The Count Scale Factor Value can range from 0.0001 to 99.9999.
Note: The precision of a counter application cannot be improved by using a
scale factor greater than one. To accomplish greater precision, more pulse
information must be generated per measuring unit.
8. RATE ENABLE (rAtE Enb)
Selecting “YES” enables the rate indicator function. If disabled (NO), the
rate programming steps will not appear. This affects the rate only.
9. RATE DECIMAL POINT (rAtE dP)
Select the desired decimal point position for the rate display, independent of
the count display.
0
0.0
0.00
0.000
0.0000
0.00000
10. RATE DISPLAY(rAtE dSP)
Program the desired rate display value which corresponds to the programmed
rate input (rate INP) value. The rate display value can be programmed from
000001 to 999999.
11. RATE INPUT(rAtE INP)
Program the rate input value that should correspond to the rate display (rate
dSP) value. The rate input value can be programmed from 00000.1 to 99999.9
and should correspond to the signal input frequency.
12. MINIMUM UPDATE TIME (Lo-Udt)
This is the minimum amount of time between display updates for the rate
display. This affects the rate display only. The low update time ranges from 00.1
to 99.9 seconds. To assist in stabilizing an erratic display, increase Lo-Udt for a
display averaging effect.
13. MAXIMUM UPDATE TIME (Hi-Udt)
This is the maximum amount of time before the rate display goes to zero. The
rate display goes to zero if the time between successive pulses exceeds the high
update (Hi-Udt) time. The high update time ranges from 00.1 to 99.9 seconds.
14. DISPLAY SCROLL (dSPScroL)
The unit can be programmed to automatically toggle between the rate display
and count displays by selecting “YES”. The display time for each display is
fixed and is approximately four seconds per display.
15. USER INPUT (USEr INP)
The User Input is activated when the user terminal is connected to common.
The function of the User Input can be programmed for one of the following.
Reset (rESEt) - A low level resets the count(s) to zero and as long as the input
is low, the unit will not process the input signal.
Store/Reset (Stor-rSt) - A low level freezes the display. The internal count(s)
are reset to zero and the unit accumulates counts even when the user input is
held low. The count value(s) update when the user input goes high.
Store (StorE) - A low level freezes the display and the unit continues to
accumulate counts. The count value(s) update when the user input goes high.
Inhibit (INHIbIt) - A low level “freezes” the display and the input signal is
ignored.
Select Display (dSPSEL) - A low level toggles between the rate display and
count display(s).
16. USER INPUT ASSIGNMENT (USEr ASg) -
(INP A-b is “dUAL cnt” and USEr INP not “dSPSEL”)
If the CUB5 is programmed for the “dUAL cnt” mode, the User Input may
be assigned to:
- (totAL) “A” Counter
- (b totAL) “B” Counter
- (both) “A” and “B” Counters
17. FACTORY SETTINGS (FACt SEt)
All of the parameters are restored to the factory default settings when YES is
selected and the front panel select button is pressed. The CUB5 displays
“LOAd” for several seconds and then returns to programming of INP A-b
(Count Mode) parameter. Factory settings for all the programmable values are
listed below.
INP A-b cnt ud
dSPSEL YES
rSt Enb YES
tot dP 0
SCLFAC 01.0000
rAtE Enb YES
rAtE dP 0
rAtE dSP 001000
rAtE INP 01000.0
Lo-Udt 01.0
Hi-Udt 01.0
dSPScrol No
USEr INP rESET
SCALING FOR COUNT INDICATION
The CUB5’s scale factor is factory set to 1, to provide one count on the
display for each pulse that is input to the unit. In many applications, there will
not be a one-to-one correspondence between input pulses and display units.
Therefore, it is necessary for the CUB5 to scale or multiply the input pulses by
a scaling factor to achieve the desired display units (feet, meters, gallons, etc.)
The incoming pulses are multiplied by the count scale factor value and stored
in the internal count register which results in the desired count display value.
The scale factor is a prescaler, which means changing the scale factor does not
change the existing internal count, but only effects the incoming pulse count.
The Count Scale Factor Value can range from 0.0001 to 99.9999. It is
important to note that the precision of a counter application cannot be improved
by using a scale factor greater than one. To accomplish greater precision, more
pulse information must be generated per measuring unit. The following formula
is used to calculate the scale factor.
Scale Factor =
Desired Display Units
x Decimal Point Position
Number of Pulses
WHERE:
Desired Display Units: Count display units acquired after pulses that occurred.
Number of Pulses: Number of pulses required to achieve the desired
display units.
Decimal Point Position:
0=1
0.0 = 10
0.00 = 100
0.000 = 1000
0.0000 = 10000
0.00000 = 100000
EXAMPLE: The counter display is used to indicate the total number of feet
used in a process. It is necessary to know the number of pulses for the desired
units to be displayed. The decimal point is selected to show the resolution in
hundredths.
Scale Factor =
Desired Display Units
x Decimal Point Position
Number of Pulses
Given that 128 pulses are equal to 1 foot, display total feet with a one-
hundredth resolution.
Scale Factor =
1.00
x 100
128
Scale Factor = 0.007812 x 100
Scale Factor = 0.7812
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