Section 7 Additional Installation Tips
Galvanic Isolation
If there is a substantial distance between the relay contacts for 24 V DC and
230 V AC, it is OK to use the same 24 V devices for all feeds. See 3 in drawing
above.
Connect 0 V on the 24 V feed to the ground, see 4 in drawing above. This offers
three advantages:
•
Safety is increased. The 24 V feed is not live in the event of a faulty connection
or short circuit between 0 V (24 V) and 230 V phase.
•
Transients on the 24 V feed are connected to the ground.
•
No risk that the 24 V feed is at a high level in relationship to the ground. This
is not unusual since there is high static electricity.
Galvanic Isolation
USB
USB
RS232
RS422/485
+24 V DC
0 V
Filter
DC/DC
galvanic isolation
VCC
0 V (GND)
DC/AC
CFL
Ethernet
Internal electronics
1.5 m
The operator panel has galvanic isolation against the 24 V DC feed but no galvanic
isolation between the communication ports for RS232, RS422/485 and USB. Only
the Ethernet connection has galvanic isolation.
*
*
*
*
*
*
*
*
*
Operator panel
Modular controller
Printer
PC
PC
Different ground potential
*
= Internal 0 V (GND) connection
Power CPU
COM COM2
RS422
RS232
USB
3BSE069463-600 Rev D
41
Summary of Contents for PP885
Page 1: ...Compact Product Suite Panel 800 Version 6 PP885 Hardware and Installation ...
Page 2: ......
Page 3: ...Panel 800 Version 6 PP885 Hardware and Installation ...
Page 6: ...6 3BSE069463 600 Rev D ...
Page 16: ...Appearance of Air in Touch Screen Section 2 Safety Precautions 16 3BSE069463 600 Rev D ...
Page 24: ...Section 4 Technical Data 24 3BSE069463 600 Rev D ...
Page 32: ...PP885 Outline Section 6 Operator Panel Drawings 32 3BSE069463 600 Rev D ...