Siemens SIMATIC FM 353, Manual

Page: 39 / 361

Wiring
4-7
FM 353 Stepper Drive Positioning Module
6ES7 353-1AH01-8BG0
Signal parameters of the outputs
All output signals are output by way of differential-signal line drivers in compliance
with Standard RS422. To ensure optimum noise immunity, the power section
should feature differential signal receivers or optical coupler inputs to permit bal-
anced signal transfer. Unbalanced transfer is also possible, however cable length
in such cases is limited to a maximum of 10 m.
Note
In the case of asymmetrical transmission satisfactory functioning cannot be guar-
anteed because of the various non-standardized input circuits of the drive units.
Especially the lead length and the limit frequency depend on the properties of the
input circuit and the lead used. Furthermore, the reference potential GND must be
floating in order to prevent electrical interference.
Table 4-3 provides a summary of the output signal electrical data.
Table 4-3 Electrical parameters of the stepper drive signal outputs
Parameters min max Unit when
Differential output voltage V
OD
2 V
RL = 100
Ω
Output voltage “High” V
3,7 V I
O
= − 20 mA
Output voltage “High” V
OH
4,5 V I
O
= − 100
µ
A
Output voltage “Low” V
OL
1 V I
O
= 20 mA
Load resistance R
L
55
Ω
Output current I
O
60 mA
Pulse frequency f
p
200 kHz
Connecting cable to drive
allowable length ( l ):
for balanced transfer, 35 m
for unbalanced transfer, 10 m