Array electronic TC-Pro482CRA, User Manual, Page: 25 / 56

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Multifunction LCD Digital Timer/Counter/Tachometer
Tachometer output mode (totm)
Set the output method for control output based on
the OUT1/OUT2 set value. Upper and lower limit
(HI-LO), area (AREA), upper (HI-HI),and lower limit
(LO-LO) can be set.
Counting speed (cnts)
Set the maximum counting speed (30Hz/10KHz) for
CP1 input. If contacts are used for input signals, set
the counting speed to 30Hz. Processing to eliminate
chattering is performed for this setting.
Decimal point position (dp)
Decide the decimal point position for the
measurement value, OUT1 set value, and OUT2
set value.
Prescale value (pscl)
It is possible to display the rate of rotation or the
speed of a device or machine to which the
TC-Pro482 is mounted by converting input pulses to
a desired unit. If this prescaling function is not used,
the input frequency (Hz) will be displayed.
The relationship between display and input is
determined by the following equation. Set the
prescale value according to the unit to be displayed.
Displayed value=input pulse frequency×prescale
value
Displaying rotation rate
Display unit Prescale value
rpm 1/N*60
rps /N
N: number of pulses per revolution
Example: in order to display the rate of rotation for a
machine that outputs 10 pulses per revolution in the
form □□□.□□□rpm:
Set the decimal point position to 3 decimal
place
Using the formula, set the prescale value
to 6
Displaying speed
Display unit Prescale value
m/min πd*1/N*60
m/s πd*1/N
N: number of pulses per revolution
d: diameter of rotating body
πd: circumference
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2 .
2 .
Average processing (aug)
Flickering display and output chattering can be
prevented using average processing (simple
averaging). Average processing can be set to one
of four levels: no average processing, 2 times (i.e.,
the average of 2 measurement values), 4 times,
8 times. The measurement cycle will be equal
to the sampling cycle (100ms) multiplied by the
average processing setting (i.e., the number of
time). Average processing enables fluctuating input
signals to be displayed stably. Set the optimum
number of times for the application.
Auto-zero time (autz)
It is possible to set the TC-Pro482 so that if there
is no pulse for a certain time the display is force-
set to 0. This time is called the auto-zero time. Set
the auto-zero time to a time slightly longer than
the estimated interval between input pulses and
within the setting range (00.01~99.99s). It will not
be possible to make accurate measurements if the
auto-zero time is set to a time shorter than the input
pulse cycle. Setting a time that is too long may also
result in problems, such as a time-lag between
rotation stopping and the alarm turning ON.
Startup time (stmr)
In order to prevent undesired output resulting from
unstable input immediately after the power supply
is turned ON, it is possible to prohibit measurement
for a set time (00.00~99.99s), the startup time. It
can also be used to stop measurement and disable
output until the rotating body reaches the normal
rate of rotation, after the power supply to the
TC-Pro482 and rotating body are turned ON at the
same time.
Display
Startup time
Time
Comparison value
(lower limit)
Power supply
Output
(lower limit)
NPN/PNP input mode (imod)
Select either NPN input (no-voltage input) or PNP
input (voltage input) as the input format. The same
setting is used for all external inputs.
Explanation of Tachometer Functions
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