Installing the S7-400

Connection to the Reference Point

For the connection to the reference point, use a cable lug for M4, a suitable spring lock washer (for example, clamping washer to DIN 6796) and the cylinder-head screw supplied.

Ungrounded assembly: Undo the fixing screws of the metallic connection on the rack. Tilt the connection downwards. For the connection to the reference point, use the original M4 x 8 supplied. Use the tilted metallic connection as a washer.

Grounded assembly: Leave the metallic connection on the rack. For the connection to the reference point, use the original M4 x 8.

Ungrounded configuration

Grounded configuration

 

Rack

 

Metallic connection

 

Reference point

Connection

Connection

Spring lock washer

Spring lock washer

Original screw with spring lock washer

Original screw with spring lock washer

M4 x 8

M4 x 8

Note

Do not use any cylinder-head screws that are longer than 6 mm for the connection to the reference point. Otherwise, you may create an undesired connection bet- ween the reference point and the rack profile behind it and therefore the connec- tion for the chassis ground. For this reason as well, leave the metallic connection on the rack and use it as a washer in an ungrounded configuration.

Automation System S7-400

Hardware and Installation

2-17

A5E00850741-01

 

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Image 33
Siemens S7-400 installation manual Connection to the Reference Point, Ungrounded configuration Grounded configuration, M4 x