Elektro-Automatik PSI 9000 DT Series, Руководство по эксплуатации

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EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
ea1974@elektroautomatik.de
PSI 9000 DT Series
3.11 Other applications
3.11.1 Series connection
Series connection of two or multiple devices is basically possible, but for reasons of safety and isolation following
restrictions apply:
• Both, negative (DC-) and positive (DC+) output poles are coupled to PE via type X capacitors,
limiting the max. allowed potential shift (see technical specs for rating)
• Remote sensing must not be connected!
•
Series connection is only allowed for devices of the same and with the same ratings, but at
least same current rating, i.e. power supply with power supply like, for instance, PSI 9080-60
DT with PSI 9080-60 DT or PSI 9080-60 T or similar
Series connection isn’t explicitly supported by additional connectors and signals on the devices. Nothing else than
output current and voltage is shared. It means, all units have to be controlled separately regarding set values and
DC output status, whether it’s manual or remote control.
According to the limit of the potential shift that comes with series connection (also see sections
„2.3.6. Grounding
of the DC output“
and
„1.8.3. Specific technical data“
, item “Insulation”
)
, models with a certain nominal output volt-
age must not be connected in series at all, like the 750 V model. There the DC minus is only isolated up to ±400 V
DC against PE. On the contrary, two 360 V units are allowed to be connected in series.
The analog interfaces of units in series connection are also allowed to be wired in parallel, because they are gal-
vanically isolated from the device and the DC output. The grounds (AGND, DGND) on the analog interfaces are
furthermore allowed to be directly connected to PE, like it can automatically happen when controlling and directly
connecting the analog interface a PC, because the ground inside PCs is usually directly tied to PE.
3.11.2 Parallel operation
Multiple devices of same kind and ideally same model can be connected in parallel in order to create a system
with higher total current and hence higher power. This can be achieved by connecting all units to the DC load in
parallel, so the single currents can add. There is no support for current and thus power balancing between the
individual units, like in form of a master-slave system. All power supplies would have to be controlled and set up
separately. However, it’s possible to have a parallel control by feeding the signals on the analog interfaces. There
are a few general points to consider and adhere:
• Always make parallel connections only with devices of same voltage, current and power rating
•
Never connect DC cables from power supply to power supply, but instead from every power supply directly to
the load, else the total current could exceed the current rating of the DC output clamps
3.11.3 Operation as battery charger
A power supply can be used as a battery charger, but with some restrictions, because it misses a battery supervision
and a physical separation from the load in form of a contactor, which is usually featured with true battery chargers
as a protection against overvoltage or reversed polarity. A sort of a battery supervision and management can be
achieved by creating custom software or also by using the battery test function in the software EA Power Control.
Following has to be considered:
•
No false polarity protection inside!
Connecting a battery with false polarity will damage the power supply
severely, even if it isn’t powered.
• All models of this series have an internal high resistive base load. This load would discharge a permanently
connected battery slowly but constantly, even if the device isn’t powered, and perhaps down to deep discharge.
It’s thus recommend to leave batteries connected only as long they’re charged (normal charge, trickle charge).