Installing the S7-400
2-14
S7-400 and M7-400 Programmable Controllers, Installation Manual
C79000-G7076-C424-01
2.5 Chassis Terminal Connection in the Non-Isolated Configuration
Reference Point
The racks offer the option of connecting the 24-V load voltage ground in the
non-isolated configuration to the 5-V ground (reference potential M, logic ground).
Connect the chassis ground to the reference point for non-isolated modules. The
reference point is metallically connected to the reference potential M.
The following figure shows the location of the reference point on a rack.
Chassis ground terminal
Reference point
Connecting to the Reference Point
For the connection to the reference point, use a cable lug for M4, a suitable spring
washer (for example, strain washer to DIN 6796) and an M4 x 6 cylinder-head
screw.
Note
Do not use any cyclinder-head screws longer than 6 mm for the connection to the
reference point. Otherwise, you may create an undesired connection between the
reference point and the rack profile behind it and therefore the connection for the
chassis ground.
www.PLCworld.cn
To Next Page
Loading...
