and Connecting the
System
4.1.2
Power Supply
for the
Basic Unit
The
must be operated with an electrically isolated power supply. The rated voltage is
24
V DC.
24 V DC Power Supply for the
If your automation system is made up of basic units
you can use the same power supply
for both basic units. This is possible because basic units
have high-grade internal
facilities for monitoring the 24 V DC voltage supply.
Note that in the event of an impermissible voltage rise (V 33 V DC) a fuse in the basic unit will
blow. This fuse is installed for safety reasons and you must not replace it yourself under any
circumstances.
24 V DC power supplies must have the following characteristics:
. Safe (electrical) isolation to DIN
0551/EN 60742 and DIN
0160
For special applications, it might be necessary to observe additional requirements (see rules and
regulations in Chapter 1 )
. 24 V DC rated voltage
- Permissible tolerance: 20 V to 30 V (including ripple)
. Mains buffering
20 ms
We recommend you to use the power supplies of our
range in the
How to Connect the Power Supply to the
Basic Unit
Connect terminals
L +
and
M of
the power supply to the corresponding terminals of the basic
unit (see Figure 4-4).
Connect terminal 5 of the
basic unit with the standard mounting rail.
Figure 4-4. Connecting the Power Supply to the Basic Unit
4-4
EWA 4NEB 8126210-02