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7.3. Parallel Operation
Devices of the same type can be connected in
parallel to increase both redundancy and power. The
default setting does not have to be adjusted.
If the output voltage is adjusted, an even current
distribution can be ensured by precisely setting all
power supplies that are operated in parallel to the
same output voltage.
To ensure symmetrical current distribution we
recommend that all cable connections from the power
supply to the DIN rail are the same length and have the
same cross section.
Depending on the system, for parallel connection of
more than two power supplies a protective circuit
should be installed at each individual device output
(e.g., decoupling diode or DC fuse). This means that in
the event of a secondary device fault high return
currents are avoided.
7.4. Redundancy Operation (Figure 17)
Redundant connections are designed for supplying
systems, which place particularly high requirements on
operational safety. If a fault occurs in the primary circuit
of device 1, device 2 automatically takes over the
complete power supply without interruption and vice
versa.
For this purpose, the power supplies to be connected
in parallel must be large enough that the total current
requirements of all loads can be fully met by one power
supply.
External decoupling diodes are required for 100%
redundancy.
7.5. Power Increase (Figure 18)
The output current can be increased to n x I
N
where
n is the number of devices connected in parallel.
The parallel connection for power increase can be
used to extend existing systems. A parallel connection
is recommended if the power supply does not cover the
current consumption of the most powerful load.
Otherwise, the loads should be divided over
independent individual devices.
A maximum of five devices can be connected in
parallel.
Power Supply, Primary Switch Mode for Universal Use – QUINT 12 V DC/10 A
+ – + –
–+
+
–
QUINT QUINT
Σ =
Figure 17
10 A 10 A
10 A
+ – + –
–+
+
–
QUINT QUINT
Σ =
Figure 18
10 A 10 A
20 A
PHOENIX CONTACT 12/15/02 TNR: 5107830-00 http://www.phoenixcontact.com
