Applications; Parallel Connection To Increase Power Rating - Siemens SITOP PSU8600 Manual

Applications

12.1

Parallel connection to increase power rating

To increase the power rating, two SITOP PSU8600 power supplies can be directly
connected in parallel.
The following must be observed:
● The cables connected to each basic unit at terminals "Output" and "0 V" must have, as far
as possible, identical lengths and the same cable cross-sections (or the same
impedance) up to a common external connection point (terminal strip).
● The basic units connected in parallel must be switched on simultaneously with a common
switch in the line feeder cable (e.g. with the main switch available in control cabinets).
● The output voltages measured in no-load operation for the basic units that are not yet
connected in parallel should not deviate more than a maximum of 50 mV. If the output
voltages differ by more than this value, then the "0 V" terminals should be connected
together, and in no-load operation the voltage difference between the "Output" terminals
(that are still not connected with one another), measured and adjusted to be the same
using the voltage potentiometer. The voltage difference should not exceed 50 mV.
● Select the "soft" output characteristic at DIP switch "SOC1" of each basic unit, see
Chapter "Setting the output characteristic (Page 97)".
NOTICE
Protective circuit when convicting more than two basic units in parallel
When connecting more than two basic units in parallel, additional measures must be taken
to prevent high backward feeding currents in the event of a secondary device fault. For this
purpose, a suitable protective circuit (e.g. decoupling diode or DC-capable circuit breaker)
must be installed between each "Output" terminal of the basic units and the common
connection point.
Power supply system SITOP PSU8600
Manual, 09.2018, A5E36758446-5-76
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