Fix The Ncu Using Spacers; Mounting The Ncu Without Spacers - Siemens SINUMERIK 840D sl Manual

6.3

Fix the NCU using spacers

Introduction
Spacers can be used to mount the NCU on a bare-metal highly-conductive rear panel of a
control cabinet.
Note
The mechanical stability for horizontal mounting is only guaranteed with the help of supports
or similar. These must be clarified depending on the specific application and are not part of
this documentation.
Procedure
Mount the NCU using two M6 screws (6 Nm tightening torque) on the spacers on the rear of
the control cabinet.
6.4

Mounting the NCU without spacers

Introduction
The NCU 710.3 PN and all of the .3B versions can be directly mounted onto the rear panel of
the control cabinet without spacers.
Procedure
The NCU has a metal clip on the upper rear side that is pushed in and fixed using 3x M3 torx
screws when supplied.
1. Remove the spacers with a T10 screwdriver .
2. Loosen the three M3 screws on the clip and push the clip up until the upper hole protrudes
3. Retighten the 3x M3 screws (0.8 Nm) of the clip.
4. Attach the top and bottom of the NCU directly on the rear panel of the control cabinet using
NCU 7x0.3 PN, NCU 7x0.3B PN
Manual, 06/2014, 6FC5397-1EP40-5BA1
beyond the housing.
two M6 screws (6 Nm);
Distance between the drilled holes, see Figure 6-1 Panel cutout (dimensions in mm)
(Page 42)
6.4 Mounting the NCU without spacers
Assembling
41