BML SF2-I2 _ _ -A/QZ _ _ - Z _ _ 5-...
Incremental magnetic encoder system
6
Interface (continued)
Minimum
Minimum
Minimum
edge
counting
sampling
distance
frequency
rate [kHz]
[kHz]
11 0.11 µs
5
26 0.26 µs
2
42 0.42 µs
1
94 0.94 µs
0,6
N1 1.8 µs
0,3
J3 3.5 µs
0,15
A7 7 µs
0,079
B4 14 µs
0,039
Tab. 6-4:
Connection between minimum edge separation, counting
frequency, sampling rate and signal frequency
For more information, see section Digital type
code (BML SF2-...-Q...) on page 29.
6.2.2
Additional parameters for rotary applications
The BML position measuring system enables the recording
of rotary movements in conjunction with a magnetic ring.
The resolution in degrees or the increments per revolution
of the system depend on the resolution of the sensor head
and the number of poles and the pole width on the
magnetic ring.
Increments per rotation
Increments per rotation
Number of poles × pole width
=
Sensor head resolution
= Number of poles × sensor head interpolation factor
System resolution
Resolution [°] =
Increments per rotation
360° × sensor head resolution
=
Number of poles × pole width
=
Number of poles ×
Converting resolution in degrees to angular seconds:
Resolution ["] = Resolution [°] × 3600
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Signal frequency
(basic oscillation)
[kHz]
10
20
4
20
2
12
1,2
6
0,6
3,2
0,3
1,5
0,15
0,79
0,079
0,38
360°
360°
sensor head
interpolation factor
Maximum speed
The selection of the resolution and edge separation of the
sensor head determines the maximum movement speed
that the sensor can detect.
The maximum rotational speed that can be detected is
determined by the interaction with the selected magnetic
ring.
60 × max. movement speed [m/s]
Max. speed [min
] =
–1
π × magnetic ring diameter [m]
For information on maximum movement speed and
minimum edge separation, see Tab. 6-3 and Tab. 6-4 on
page 20.
Recommendation: max. speed 10% less than the
detected speed value.
A complete technical description and calculation
examples can be found in the document titled
User's Guide – Magnetic Rings (see Tab. 10-2
on page 30).
The following conditions must be met in order to
achieve the position measuring system's
maximum speed:
– The sensor head can detect this speed
– The magnetic ring mechanism is designed for
this speed
english
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