Siemens SIMOTRAS 6SG7050, Руководство по эксплуатации

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Connections 01.04
6-34
SIEMENS AG 6SG7000-0BA76
SIMOTRAS HD Operating Instructions
If the pulse encoder is incorrectly matched to the encoder cable, disturbing cable reflections will be produced
at the receive end. These reflections must be damped so that the encoder pulses can be correctly evaluated.
The limit values listed in the table below must be maintained to ensure that the resultant power loss in the
adapting element of the evaluation electronics is not exceeded.
Table 2:
f
max
50kHz 100kHz 150kHz 200kHz 300kHz
Differential voltage 3) Up to 27V Up to 22V Up to 18V Up to 16V Up to 14V
3
)
Differential voltage of encoder pulses at no load
(approximate encoder power supply voltage)
Cable, cable length, shield connection:
The encoder cable capacitance must be recharged at each encoder edge change. The RMS value of this
current is proportional to the cable length and the pulse frequency and must exceed the current specified by
the encoder manufacturer. A suitable cable as recommended by the encoder manufacturer must be used.
The maximum cable length must not be exceeded. Generally, a twisted cable pair with common pair shield is
sufficient for each track. Crosstalk between the cables is thus reduced. The shielding of all pairs protects
against noise pulses. The shield must be connected to the shield bar of the SIMOTRAS converter over the
largest possible surface area.