Connect Metal Shield In The Terminal Box; Radio-Frequency Grounding For Converter Operation - Siemens SIMOTICS 1PQ8 Operating Instructions Manual

As an alternative, you can connect the grounding conductor without cable lugs using a terminal
plate at the marked connection point.
Connecting the grounding conductor
● Ensure that the connecting surface is bare and is protected against corrosion using a
● Arrange the flat washer and spring washer under the bolt head.
● Check that the maximum permissible clamping thickness of 10 mm for the cable lug or strap
● Fasten the clamping screw according to the following table. Screw-in depth and tightening
● Use the connecting terminals designated for the grounding conductor in the terminal box.
6.3.5

Connect metal shield in the terminal box

If you are using metal-armored cables that are inserted into the terminal or auxiliary terminal
boxes with non-intrinsically safe circuits, then ground the metal shield in the terminal box.
Additional grounding points are permissible.
● In terminal boxes with internal grounding part, connect the metal shield to the internal
● In terminal boxes without internal grounding part, connect the metal shield to one of the
6.3.6

Radio-frequency grounding for converter operation

In converter operation, the converter emits RF alternating currents. To establish and RF-
specific optimal connection between motor terminal box and motor enclosure, you can use
flexible braided copper flat cables with low impedance and a broad frequency range.
Establish the radio-frequency ground connection with flat cables. Alternatively you can
establish the radio-frequency ground connection with cable lugs.
SIMOTICS TN Series N-compact 1PQ8
Operating Instructions 11/2018
suitable substance, e.g. acid-free vaseline.
is not exceeded.
torque are different depending on whether cable lugs or ground terminals are used.
When using cable lugs
When using grounding
terminals
grounding point.
green-yellow grounding terminals.
Screw Screw-in depth
M6
M8
M12 x 25
M16 x 35
M6
M8
M10
M12
M16
Electrical connection
6.3 Preparation
Tightening torque
> 6 mm
> 8 mm
> 16 mm
> 20 mm
> 9 mm
> 12 mm
> 15 mm
> 18 mm
> 20 mm
8 Nm
20 Nm
38 Nm
92 Nm
8 Nm
20 Nm
40 Nm
70 Nm
170 Nm
73