Siemens SINAMICS DCM Manual page 178

The encoder type is selected using p0400. The evaluation electronics are adjusted
electronically to the encoder signal voltage:
Rated input voltage
Encoder
Low signal level (differential voltage)
High signal level (differential voltage)
Hysteresis
Common-mode controllability
If the incremental encoder does not supply any symmetrical encoder signals, it must be
grounded with each signal cable twisted in pairs and connected to the negative connections
of track 1, track 2, and zero mark.
Switching frequency:
The maximum frequency of the encoder pulses is 300 kHz. To ensure the encoder pulses
are evaluated correctly, the minimum distance (Tmin) between two encoder signal edges
(track 1, track 2), as listed in the table, must be adhered to.
Rated input voltage
Differential voltage 1)
Tmin 2)
1) Differential voltage at the terminals of the evaluation electronics
2) The phase error LG (deviation from 90°) that may occur as a result of the encoder and
cable can be calculated on the basis of Tmin:
LG= ± (90° – fp × Tmin × 360°)
LG = Phase error
fp = Pulse frequency
Tmin = Minimum edge distance
This formula only applies if the pulse duty factor of the encoder signals is 1:1.
If the incremental encoder is incorrectly matched to the encoder cable, disturbing cable
reflections will occur at the receiving end. To ensure that encoder pulses of this type can be
evaluated without errors, these reflections need to be damped. The limit values listed in the
table below must be adhered to in order to prevent the resulting power losses in the
evaluation electronics adaptor from being exceeded.
fmax
Differential voltage 3)
3) Differential voltage of encoder pulses without load (= approximately the supply voltage of
the incremental encoder)
Cable, cable length, shield support:
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 pulse frequency, and must not
exceed the current permitted by the encoder manufacturer. A suitable cable that meets the
recommendations of the encoder manufacturer must be used, and the maximum cable
length must not be exceeded.
SINAMICS DCM DC Converter
Operating Instructions, 02.2015, A5E34763375/RS-AA/001
5 V
2 V
630 ns
50 kHz
≤ 27 V
ac.maher.co.ir
6.9 Assignment of terminals and connectors
5 V
TTL
< 0.8 V
> 2.0 V
> 0.2 V
±10 V
> 2.5 V 8 V
380 ns 630 ns 430 ns
100 kHz 150 kHz 200 kHz
≤ 22 V ≤ 18 V ≤ 16 V
Connecting
15 V
HTL
< 5.0 V
> 8.0 V
> 1.0 V
±10 V
15 V
10 V > 14 V
380 ns
300 kHz
≤ 14 V
179