TM5-250_B
9
LP0859X 10/10
REVIEWING THE FRONT BUTTONS & DISPLAY
KEY
DISPLAY MODE OPERATION
PROGRAMMING MODE OPERATION
PAR
Access Programming Mode
Store selected parameter & index to next parameter
▲
No Function
Increment selected digit of parameter value
▼
No Function
Select digit position in parameter value
SCALING THE METER
RATE SCALING
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 Hz. A linear relationship is formed
between these points to yield a rate display value that corresponds to the incoming input signal rate. The
location of the scaling point should be near the process end limit for the best possible accuracy. The
TACHTROL 20 is capable of showing a rate display value for any linear process.
SCALING CALCULATION
If a display value versus input signal (in pulses per second) is known, then those values can be entered
into Scaling Display
(rt-dSP)
and Scaling Input
(
rt-INP
).
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:
NOTES:
1. If number of pulses per unit is less than 10, then multiply both Input and Display values by 10.
2. If number of pulses per unit is less than 1, then multiply both Input and Display values by 100.
3. 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 the number 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. Both values must be greater than
0.0.
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
RATE PER
DISPLAY
(rt -dSP)
INPUT (
rt
-
INP)
SECOND
1
# PULSES PER UNIT
MINUTE
60
# PULSES PER UNIT
HOUR
3600
# PULSES PER UNIT
