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Example 2:
By setting MUL = 38 and DIV = 1, you get a parameter in engineering units. Therefore, with each pulse actually counted the display will increment as follows:
Counter display in engineering units
0, 38, 76, 114, .... etc. pulses actually counted
0, 1, 2, 3, ...... etc.
i.e., by setting a preset of 1000,
•
i.e.,
1000
1
------------------ = 26
38
N.B.: Since the setting (1000) cannot be divided evenly by the MUL factor (38), the instrument automatically rounds the setting off to the closest lower value. In this
case,
1000
------------ = 26,31 . . .
38
Decimals are ignored and the setting is automatically revised to 26x38=988.
Programming the FREQUENCY METER (Function Typ=2)
In normal operation, display A shows the current frequency. Frequency setpoint and hysteresis values (for type U4 output) are set with the raise/lower buttons.
The setpoint is changed immediately; hysteresis is selected with the F key. Frequency meter operating mode is defined by parameter FP (see Configuration pro-
cedure). For values 0, 1 and 2, the instrument measures frequency in the range 0.03 - 5000 Hz, with 1/1000 precision on full scale and mobile decimal point, to
achieve the maximum precision possible with 4 figures. In this case, parameter P.d. represents the decimal point position only for the setpoint and for hysteresis.
For FP values 4, 5 and 6 after parameter P.d., parameter t.SP appears as settable sampling time, and the instrument counts the pulses arrived during this time. The
role of P.d. doe not change.
For FP values 8, 9 and 10, the instrument measures frequency as for 0, 1 and 2, but with fixed decimal point, set with P.d., which in this case represents the posi-
tion of the point not just for the setpoint and hysteresis. Values 12, 13 and 14 are with sampling time and fixed decimal point. The displayed value can be expressed
in engineering units by setting the MUL and DIV functions: displayed value = frequency *MUL/DIV.
Example 1:
You want to display the number of rpms of a wheel with 250 pulses/rev. Rpm = frequency *60/250 = frequency *6/25
Set FP = 0, MUL = 6, DIV = 25
Example 2:
You want to determine the frequency in impulses/second of a system, with a decimal figure, using a sampling time of 5 sec for greater stability. Set FP = 12, MUL =
1, DIV = 5, P.d. = 1, t.SP = 5.0.
In operation as frequency meter, the only available output functions are U1 and U4, the latter with hysteresis below the setpoint value when the relay is de-ener-
gized.
Introduction
Configuration is performed in a single procedure and consists of 14 settable parameters. To access Configuration (if the hardware protection has been removed)
keep button F pressed until the CFG message appears on display A (display B = x.x n. software release). Then press the F key briefly to scroll the various functions
(parameters) to be set so that the instrument can be configured as required.
The symbol for the parameter shown on display B will appear on display A. Press the F key for about 5 seconds to quit the configuration procedure. The display
returns to the "real" time/count.
Configuration (CFG) procedure
(accessible only with jumper S10 closed)
Pro/ software protection level
0 - display and change of setpoint with saving of current count in EEPROM at shutdown (556 only)
1 - display of setpoint with saving of current count in EEPROM at shutdown (556 only)
2 - display and change of setpoint without saving
3 - display of setpoint without saving
To assure correct saving, do not change the setpoint or scale when a count is in progress.
Typ/ instrument type :
0 - Timer
1 - Counter
2 - Frequency meter
Fun/count mode and enabling of automatic scale change during setting of timer setpoints (for timer and counter)
0 - count-down with automatic change of time scale
1 - count-up with automatic change of time scale
2 - count-down without automatic change of time scale
3 - count-up without automatic change of time scale
Note : "Automatic change of time scale" regards scales in seconds only.
FP/ frequency meter operating mode.
4
6 • PROGRAMMING
MOL
38
----------
=
---------
DIV
1
•
1000
DIV
------------------ real pulses will have to be counted before reaching the preset
MOL
7 • SOFTWARE CONFIGURATION
= 38
80469C_MHW_556_02-2011_ENG
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