Lenze EDB9300UES User Manual

Page 47

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Technical Data

42

BA8230

Ratings and connection

To compensate for interference (push-pull interference) on cables, encoders with two
pulse tracks offset through 90° electrical and with complimentary outputs are used. To
guarantee high resistance to interference it is recommended that encoders with a 24
V operating voltage are used.

The quality of the encoder cable is critical for the maximum encoder frequency which
can be transmitted. Screened cables with conductors twisted in pairs are to be used.
The screen is connected at both ends.
In the system, encoder cables must be laid separately from power cables (spacing

0.3 m for up to 200 m cable length). It is recommended that the encoder cable be
connected directly to the encoder interface, without any separation points. The screen
is to be fully surrounded by clamps and connected to the control electronics cassette.
See section 3.6 for supplementary notes on connection.

Recommended encoder cable:

LIYCY 3 x 2 x 0,75 mm² (twisted in pairs)

Guideline values for possible cable lengths for incremental encoder cable

Max. encoder cable
length:

l [m]

Max. encoder frequency:

f

G

[kHz]

[

]

[

]

f

Z n Imp min

60 10

kHz

G

1

3

=

30

300

00

160

200

100

300

50

For more stringent requirements the details given by the manufacturer of incremental
encoder systems for higher transmission frequencies should also be observed and
matched sets of special cables should also be used.

Maximum speed of the drive:

n

f

Z

G

max

max

=

60 10

3

Z

Encoder pulses per revolution

[p/rev]

n

max

Max. motor speed

[rpm]

f

Gmax

Max. encoder frequency

[kHz]

Minimum speed of the drive:

n

T

Z

min

max

=

∗ ∗

60 10

2

3

T

max

Max. time between 2 pulse [ms]

with T

max

= 25 ms

For technical reasons lower values for n

min

are interpreted as motor standstill.

To achieve high resolution for speed measurement the encoder should have a high
number of pulses per revolution. At high motor speeds this is counteracted by the limit
on transmission frequency resulting from long encoder cables and the technical data
of incremental encoders.
Encoders of 1000 pulses per revolution and above are recommended. Depending on
the manufacturer, incremental encoders using a 24 V supply voltage operate up to a
maximum sensing frequency of approx. 160 kHz.

Example configurations Cable length = 100 m, frequency limit = 100 kHz.

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