Beckhoff CX51 0 Series, Руководство пользователя

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Commissioning
CX51x0 38 Version: 2.8
The cables of an external voltage source are connected to the power supply unit with spring-loaded
terminals.
Table 27: Required wire cross-sections and strip lengths.
Conductor cross-section 0,5 ... 2,5 mm
2
AWG 20 ... AWG 14
Strip length 8 ... 9 mm 0.33 inch
The voltage source has been connected to the power supply unit
successfully when the two upper power supply terminal LEDs light up in
green.
• The left LED (Us) indicates the supply of the basic CPU module and
terminal bus.
• The red LED (Up) indicates the Bus Terminal supply via the power
contacts.
NOTE
Interrupting / switching off the power supply
To switch off the Embedded PC, do not disconnect the ground (0 V), because otherwise current may con-
tinue to flow via the shielding, depending on the device, and damage the Embedded PC or peripheral de-
vices.
• Always disconnect the 24 V line. Devices connected to the Embedded PC, which have their own power
supply (e.g. a Panel) must have the same potential for "PE" and "0 V" as the Embedded PC have (no
potential difference).
Observe the UL requirements
The CX51x0 Embedded PCs are UL certified. The corresponding UL label can be found on the type plate.
Fig. 23: UL label for CX51x0 Embedded PC.
The CX51x0 Embedded PCs can thus be used in areas in which special UL requirements have to be met.
These requirements apply to the system voltage (Us) and to the power contacts (Up). Application areas
without special UL requirements are not affected by UL regulations.
UL requirements
• The Embedded PCs must not be connected to unlimited voltage sources.
• Embedded PCs may only be supplied from a 24 V DC voltage source. The voltage source must be
insulated and protected with a fuse of maximum 4 A (corresponding to UL248).
• Or the power supply must originate from a voltage source that corresponds to NEC class 2. An NEC
class 2 voltage source must not be connected in series or parallel with another NEC class 2 voltage
source.