-8-
Drawing No. LP0749
Released 2018-01-16
The Low Update Time is the minimum amount of time between
display updates for the Rate display. Values of 0.1 and 0.2 seconds will
update the display correctly but may cause the display to appear
unsteady.
RATE LOW UPDATE TIME (DISPLAY UPDATE)
to
seconds
The High Update Time is the maximum amount of time before the
Rate display is forced to zero. (For more explanation, refer to Input
Frequency Calculation.) The High Update Time
must
be higher than the
Low Update Time and higher than the desired slowest readable speed
(one divided by pulses per second). The factory setting of 2.0, will force
the display to zero for speeds below 0.5 Hz or a pulse every 2 seconds.
RATE HIGH UPDATE TIME (DISPLAY ZERO)
to
seconds
5.2 MoDule 2 - r
ate
s
etuP
P
araMeters
(
)
PAR
Rate Scaling
Display Value
Rate Decimal
Point
Rate
Enable
Rate Input
Scaling Style
Rate High
Update Time
Rate Scaling
Input Value
Rate Low
Update Time
PARAMETER MENU
RATE ENABLE
This parameter enables the Rate display. For maximum input
frequency, Rate Enable should be set to
when not in use. When set
to
, the remaining rate parameters are not accessible.
This selects the decimal point position for the rate display. This
parameter does not affect rate scaling calculations.
RATE DECIMAL POINT
RATE SCALING INPUT VALUE
RATE SCALING DISPLAY VALUE
Enter the desired Rate Display value. This value is entered using the
front panel buttons for either Scaling Style.*
Enter the corresponding Rate Input value using the Scaling Style
selected.
to
to
*For value entry instructions, refer to selection/value entry in the
Programming The Meter section.
RATE INPUT SCALING STYLE
If a Rate Input value (in Hz) and the corresponding Rate Display value
are known, the Key-in (
) Scaling Style can be used. This allows rate
scaling without the presence of a rate input signal.
If the Rate Input value has to be derived from the actual rate input
signal, the Apply (
) Scaling Style should be used.
SCALING FOR RATE INDICATION
To scale the Rate, enter a Scaling Display value with a corresponding
Scaling Input value. These values are internally plotted to a Display
value of 0 and Input value of 0.0 Hz. A linear relationship is formed
between these points to yield a rate display value that corresponds to
the incoming input signal rate. The meter is capable of showing a rate
display value for any positive slope linear process.
SCALING CALCULATION FOR KEY-IN STYLE
If a display value versus input signal (in pulses per second) is known,
then those values can be entered into Scaling Display (
) and
Scaling Input (
). No further calculations are needed.
If only the number of pulses per ‘single’ unit (i.e. # of pulses per foot)
is known, then it can be entered as the Scaling Input value and the
Scaling Display value will be entered as the following:
RATE PER
DISPLAY (
)
INPUT (
)
Second
1
# of pulses per unit
Minute
60
# of pulses per unit
Hour
3600
# of pulses per unit
NOTES:
1. If # of pulses per unit is less than 1, multiply both Input and Display
values by 10 or 100 as needed to obtain greater accuracy.
2. If the Display value is raised or lowered, then Input value must be
raised or lowered by the same proportion (i.e. Display value for per
hour is entered by a third less (1200) then Input value is a third less
of # of pulses per unit). The same is true if the Input value is raised
or lowered, then Display value must be raised or lowered by the
same proportion.
3. Both values must be greater than 0.
EXAMPLE:
1. With 15.1 pulses per foot, show feet per minute in tenths. Scaling
Display = 60.0 Scaling Input = 15.1.
2. With 0.25 pulses per gallon, show whole gallons per hour. (To have
greater accuracy, multiply both Input and Display values by 10.)
Scaling Display = 36000 Scaling Input = 2.5.
Key-in Style:
Enter the Rate Input value using the front panel buttons. This value is
always in pulses per second (Hz).*
Apply Style:
The meter initially shows the stored Rate Input value. To retain this
value, press
PAR
to advance to the next parameter. To enter a new
value, apply the rate input signal to Input A. Press
RST
and the applied
input frequency (in Hz) will appear on the display. To insure the correct
reading, wait several rate sample periods (see Rate Low Update Time)
or until a consistent reading is displayed. Press
PAR
to store the
displayed value as the new Rate Input value.