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© 2006, Elektro-Automatik GmbH & Co. KG
Irrtümer und Änderungen vorbehalten
EN
Instruction Manual
PSI 8000 3U Series
Date: 05-03-2012
Operating the device
Figure 10. Wiring remote sense
Example 2: the device is in constant current regulation, the
output voltage is defined by the resistance of the load. Then
the power is limited down. Output voltage and current are de-
creasing to values according to the formula P = U * I. Once the
current set value is decreased, the output current would also
decrease and thus the output voltage.
The product of both values, the actual power, would sink below
the previously set power limit and the device would change from
constant power regulation (CP) to constant current regulation
(CC).
Those three conditions CC, CV and CP are also indicated on the
appropriate pins of the optional, analogue interface cards or can
be read out as status bits via an optional, digital interface card.
8.7 Remote sense is active
Remote sense operation is used to compensate voltage drops
of the conductors between the power supply and the load.
Because the compensation is limited to a certain level, it is
recommended to match the cross section of the conductors to
the output current and thus minimise the voltage drop.
The sense input is located on the rear at terminal
Sense
, where
the sense conductors are connected to the load with correct
polarity. The power supply will detect the external sense au-
tomatically and compensate the output voltage by the actual
voltage at the load instead of the output. The output voltage
will be raised by the value of the voltage drop between power
supply and load.
Maximum compensation: see technical specifications, will vary
from model to model.
Also see figure 10 below.
8.8 Mains undervoltage or overvoltage occurs
The units require two or three phases of a three-phase supply
with 400V phase conductor voltage and tolerate max. +15%.
This results in an input voltage range of 340...460V AC. Within
this range, the units can be operated without any restrictions.
Input voltages below 340V AC are considered as supply under-
voltage and will store the last condition, as well as switch the
power output off. Same happens at overvoltage above 460V AC.
Permanent input undervoltage or overvoltage must be
avoided!
8.9 Connecting different types of loads
Different types of loads, such as ohmic loads (lamp, resistor),
electronic loads or inductive loads (motor) behave differently
and can retroact to the power supply. For example, motors
can induce a countervoltage which may cause the overvoltage
protection of the power supply to shut off the output.
Electronic loads have regulator circuits for voltage, current and
power that can counteract to the ones of the power supply and
may result in increased output ripple or other, unwanted side
effects. Ohmic loads are almost 100% neutral. It is recommen-
ded to consider the load situation when planning applications.
