Siemens Simatic 6ES7 157-0AC80-0 A0 Series, Руководство пользователя

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Wiring
4-14
DP/PA Link and Y Link Bus Couplings
A5E00193841-011
PA Bus terminating switch
The PA bus terminating switch is only provided on the DP/PA coupler
(6ES7 157-0AC80-0XA0). You can loop through the PROFIBUS-PA on this DP/PA
coupler only.
The bus terminating resistor cannot be deactivated in the DP/PA coupler Ex [i], i. e.
the DP/PA coupler Ex [i] must be located at the beginning or end of a PA segment.
DP/PA coupler
(6ES7 157-0AC80-0XA0)
PA bus terminating switch
OFF
ON
OFF: The bus terminating resistors are deactivated.
You can loop through the PROFIBUS-PA and con-
nect bus terminating resistors to both ends of the
PA segment.
ON: The bus terminating resistors are activated.
PROFIBUS-PA must not be looped through.
Figure 4-10 PA bus terminating switch
Procedure
Connect PROFIBUS-PA as follows:
1. Strip the insulation from the cable, turning the braided screen back over the
insulation as shown below.
Turn the braided screen back over the insulation.
15 mm 60 mm
10 mm
Figure 4-11 Length of insulation stripped
2. Clamp the shield of the bus cable under the cable grip and screw it tight.
3. Secure the conductors of the bus cable in the screw-type terminals P+ and P–.
Be sure to get the polarity of the conductors right.