Mounting Screws - Siemens SIMATIC S7-400 Installation Manual

Mounting Screws

You have a choice of the following types of screw for securing a rack:
M6 cylinder-head screw to
ISO 1207/ISO 1580 (DIN 84/DIN 85)
M6 hex. screw to ISO 4017 (DIN 4017)
Step 3: Connecting the Rack to the Chassis Ground
Connect the rack to the chassis ground. A threaded bolt is provided for this
purpose on the bottom left of the rack.
Minimum cross-section of the conductor to the chassis ground: 10 mm
If the S7-400 is mounted on a mobile rack, you must provide a flexible conductor to
the chassis ground.
Note
Always ensure that there is a low-impedance connection to the chassis ground
(see the figure below). You achieve this with the shortest possible, low-resistance
conductor with a large surface to establish large-area contact.
M6 nut
Automation System S7-400 Hardware and Installation
A5E00850741-01
Screw Type
M6 threaded bolt
Contact washer
Terminal
Plain washer
Explanation
Choose the screw length according to your
assembly.
You also need "6.4" washers to ISO 7092 You also need "6 4" washers to ISO 7092
(DIN 433).
To chassis ground
Installing the S7-400
2
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