Power Supply - Siemens IWLAN/PB Link PN IO Handbuch

2.1.1

Power Supply

Warning
!
The IWLAN/PB Link PN IO is designed for operation with safety extra-low voltage
(SELV). This means that only safety extra-low voltages (SELV) complying with
IEC950/EN60950/ VDE0805 may be connected to the power supply terminals.
The power supply unit to supply the IWLAN/PB Link PN IO must comply with NEC
Class 2 (voltage range 20.4 - 28.8 V, current requirement 300 mA).
The device must only be supplied by a power supply unit that complies with the
requirements of class 2 for power supply units "National Electrical Code, Table 11
(b)". If the power supply is installed redundantly (two separate power supplies), the
total power of both power supplies together must meet these requirements.
Exceptions:
S
Supply with PELV (complying with VDE 0100-410) is also permitted as long as
the generated rated voltage does not exceed the voltage limits 25 V AC or 60 V
DC.
S
Supply by a SELV power source (complying with IEC 60950) or PELV power
source (complying with VDE 0100-410) without restricted power is also
permitted as long as suitable fire prevention measures are taken by:
- installing in cabinet or suitable enclosure
- installing in suitably equipped, closed room
The power supply is connected over a 4-pin plug-in terminal block. The power
supply can be connected redundantly. The two inputs are isolated. There is no load
sharing. When the supply is redundant, the power source with the higher output
voltage supplies the IWLAN/PB Link PN IO alone. The power supply is connected
to the housing over a high resistance to allow ungrounded installation.
Figure 2-2 Power Supply
IWLAN/PB Link PN IO Gateway for Industrial Ethernet / Manual Part B9
Release 1/2005
C79000-G8976-C200-01_vorabversion_01
2 Installation and Commissioning
L1+: +24 V DC
M: Chassis 24 V DC
L2+: +24 V DC
M: Chassis 24 V DC
9