Beckhoff PS3031-4820-0000, Documentation, Page: 39 / 45

Application notes
PS3031-4820-0000 39 Version: 1.0
4.8 Parallel use to increase power
Power supplies from the PS3xxx series can be connected in parallel to increase the output power.
• The output voltage must be set to the same value (±100 mV) in "Single Use" mode and with the same
load conditions on all devices, or the units can be left with the factory settings.
• After the settings have been made, the jumper on the front of the device must be changed from "Single
Use" mode to "Parallel Use" mode in order to achieve load splitting.
◦ In "Parallel Use" mode the output voltage is regulated such that the voltage at no load is approx.
4% higher than at nominal load. See also Output [
}
13] chapter.
◦ If no jumper is plugged in, the device is in "Single Use" mode. The factory setting is also the
"Single Use" mode.
• If more than three devices are connected in parallel, a fuse or circuit breaker with a rated current of
30 A or 32 A is required at each output. Alternatively a diode can be used.
Restrictions:
• Maintain an installation distance of 15 mm (left/right) between two power supplies.
• Do not install the power supplies above each other.
• In "Parallel Use" mode power supplies should only be used in the standard installation position
(terminals on the underside of the device), not in other installation positions or under other conditions
that require a reduction in the output current (e.g., installation altitude, operation at temperatures about
+60°C, ...).
• Note that leakage current, electromagnetic interference, input inrush current, and harmonics increase
when using multiple power supplies.
Fig. 28: Parallel connection
4.9 Inductive and capacitive loads
The device is designed to supply all load types, including capacitive and inductive loads.
4.10 Back-feeding loads
Loads such as braking motors or inductors can feed back voltage to the power supply. This feature is also
known as back EMF. (electromagnetic force).
This power supply is stable and will not malfunction if a load is feeding back voltage to the power supply. It is
irrelevant whether the power supply is switched on or off.
The maximum permissible feed-back voltage is 63 Vdc. The absorbing energy can be calculated according
to the large built-in output capacitor indicated in the output data, see
Output [ } 13] chapter.