Technical data

6.5 Parameter Control
The voltage and current values of the sources are internally controlled by the instrument. It is
possible to choose between two protective functions when the upper or lower limits are
exceeded.
After pressing the MODE button [11] the sub-menu for setting the operating mode is accessed.
On pressing cursor buttons “
∧” and “∨” [13] the menu point for setting the parameter control
is called and the following message appears on the display [5]:
MODE
[ PROTECTION ]
With the help of the ENTER button [12] the menu point is confirmed and the following
message is displayed:
MODE
PROT: [ ]
The term in the brackets [ ]describes the current protective function. On pressing cursor
buttons “
∧” and “∨” [13] the protective function LIMITING or CUT-OUT is set. The new
setting is saved with the ENTER button [12]. If the former state is to be kept, the ESC button
[12] has to be pressed. In both cases the unit reverts to the starting state.
The selection of the protective function LIMITING causes the source working as a constant
voltage source automatically to switch to the functional mode of a constant current source
whenever the set current value is exceeded. If the source is working as a constant current
source, it automatically switches to the functional mode of a constant voltage source
whenever the set voltage value is exceeded.
The selection of the protective function CUT-OUT causes the outputs of the sources to be
deactivated whenever the upper or lower limits are exceeded. The LED above the OUT A/B
button [15] goes out and the following error message appears on the display [5]:
Error
Exceeded I limit
or
Error
Exceeded V limit
After changing the limiting values of the source or after changing the output load the outputs
of sources A [2] and B [3] can be activated again using OUT A/B button [15]. The input of
the limiting values is described in chapter 6.4.
6.6 Parameter Pre-set
The power supply unit PN 300 is provided with an EEPROM allowing five different
instrument configurations to be stored. The data are preserved after switching the instrument
off.
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Operating Instructions PN 300
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