SD34002g_e.doc / Sep-13
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7. Practical Examples for Setup and Scaling
For proper scaling of the unit is mandatory to respond to the following questions:
Which input frequency (Hz) will the encoders produce at a typical speed?
Which numeric value do we intend to display at this typical speed?
(sequence of numbers including the decimal positions)
Is the display characteristics proportional (speed) or reciprocal (time)?
The subsequent settings refer to the illustrations shown in chapter 4.
7.1. Settings for the Example a) of Chapter 4.1 (Speed Display)
Machine specifications:
Calculations:
Relevant parameters:
Encoder:
TTL A, /A, B, /B
4096 ppr.
Measuring wheel:
Circumference = 500
mm
(diameter = 159,2 mm)
Expected Line speed:
0 ... 300 meters/min
Desired display value:
0 ... 300,0 m/min
(one decimal position)
With a speed of 300 m/min
the measuring wheel will
rotate at 600 rpm.
With a 4096 ppr encoder
we will get 600 x 4096 =
2 457 600 Imp./ min equal
to 40 960 Imp /sec. (Hz)
This means at maximum
speed of 300 m/min the
encoder frequency is
40 960 Hz.
We expect a display value
of 3000 (to display 300.0)
F02.004
0
F02.0005 1
F03.022
0
F03.024
0,100 (assumed)
i.e. display cycle = 0.1 sec.
F03.025
0,10 (display zero with f < 10 Hz)
F03.027
40960
F03.028
3000
(= 300.0 with a decimal point)
F03.029
0
7.2. Settings for the Example b) of Chapter 4.1 (Baking Time)
Machine specifications:
Calculations:
Relevant parameters:
Proximity switch:
Standard PNP 3-wire
type
Sensed pinion:
16 teeth
70 rev. of the pinion =
1 meter of travelling
distance
Furnace length: 60 m
Range of baking times:
from 10 min. up to 2 h
Desired display format:
01h : 59min : 59sec
To run over the full furnace
distance of 60 meters, the
proximity will generate a
total number of impulses of
60 x 70 x 16 imp.
= 67200 impulses totally
With maximum speed we
expect a transition time of
10 min. equal to 600 sec.
With 67200 impulses in
600 seconds our frequency
corresponds to 112 Hz
F02.004
0
F02.005
0 (with clock display format
decimal points appear
automatically)
F03.022
5
F03.024
1,000 (assumed)
i.e. display cycle = 1 sec
F03.025
1,00
(frequencies < 1 Hz = standstill)
F03.027
112
F03.028
600
F03.029
Use setting "1" first and verify
correct display of seconds. Then
change over to "3" (clock format)
