BECKHOFF CX9000 - Manual (Page 18)

Product overview
16 Embedded PC
Connections
The system is supplied with power via the integrated power supply. This is wired as follows:
The basic module is powered via the upper connectors with 24 V DC. The terminal bus can be supplied via the lower
connections.
UL requirements
Danger
For the compliance of the UL requirements the CX-Controllers should only be supplied
•
by a 24 V
DC
supply voltage, supplied by an isolating source and protected by means of a
fuse (in accordance with UL248), rated maximum 4 Amp.
•
by a 24 V
DC
power source, that has to satisfy NEC class 2.
A NEC class 2 power supply shall not be connected in series or parallel with another
(class 2) power source!
These UL requirements are valid for all supply voltages of the CX-Controllers!