turck BL20 - Page 390

Guidelines for Station Planning
D301087 0308 - BL20 CANopen6-14
The C-rail can be used as required by the application, for example,
as a protective earth (PE). In this case, the PE connection of each
power distribution module must be connected to the mounting rail
via an additional PE terminal, which is available as an accessory.
C-rails can be used for a common voltage supply when relay
modules are planned. To accomplish this, the load voltage is
connected to a Power Feeding module with the BL20-P4x-SBBC
base module with tension clamp or screw connection. All the
following relay modules are then supplied with power via the C-rail.
Warning
It is permitted to load the C-rail with a maximum of 24 V. Not 230 V!
Note
For information about introducing a BL20 station into a ground ref-
erence system, please read chapter 7.
Figure 11:
Using the C-rail as
a protective earth
23
22
21
13
12
11
23 23
22 22
21 21
13 13
12 12
11 11
23 2323
22 2222
21 2121
13 1313
12 1212
11 1111
24 24
23 23
22 22
21 21
14 14
13 13
12 12
11 11
24
23
22
21
14
13
12
11
24
23
22
21
14
13
12
11
Gateway
TS
BR
SBBC
2 DO
SBC
2 DI
SBBC
2 DO
SBC
2 DI
SBB
PF
SBBC
2 DI2 DO
SBBCSBC
2 DO
SBC
2 DI
SBB
C-rail (PE) C-rail (PE)
PE
terminal