Adjustment Of The Current Limits; Activation Of Channels - Hameg Instruments Hmp4030 Handbuch

The HMP4030 delivers 0 ... 32 V for CH1, CH2 and CH3, the
available current conforms to the power hyperbola shown.
If the display shows, e.g., a voltage of 10,028 V (the
cursor points to the 3
digits to right can be set to 10,000 V by pressing the
knob.
STOP
Fig. 4.2: Available maximum values of HMP4030
The HMP4040 delivers 0 ... 32 V for CH1, CH2, CH3 and CH4, the
available current conforms to the power hyperbola shown.

4.4 Adjustment of the current limits

Current limiting to I means that this will be the maximum
max
current which the instrument will deliver to the load. This will
prevent any damage to the load in case of a short-circuit etc.
U
out
U
max
CV (Constant voltage)
Fig. 4.3: Current limit
As shown on this diagram, V
I I ; this constitutes voltage regulation. If Imax is exceeded
<
out max
current regulation will take over, i.e., even if the load increases
the current will remain limited to Imax. In current regulation
the output voltage will hence decrease below the value set. If a
channel is activated by pressing the VOLTAGE
buttons and if its settings are changed, the channel LED will
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change from green (indicating voltage regulation to red (indi-
cating current regulation) if the adjustments cause a change
of regulation mode.
After turn-on the instrument will automatically enter the voltage
regulation mode. The maximum current depends on the set-
ting of the CURRENT button
button 9 , the channel can be selected. The current limit is
adjusted either by the knob
I
10
5
0
0 16
Fig. 4.4: HMP4030/4040 power hyperbola
rd digit from the right), the
CC (Constant Current)
I
I
out
max
will remain stable as long as
out
and OUTPUT
10
9 . After pressing the CURRENT
4 , the numerical keyboard
V
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O p e r a t i o n o f t h e H M P 4 0 3 0 / H M P 4 0 4 0
or the arrow buttons
press the CURRENT button
done the instrument will automatically exit this mode after 5 s
without storage.
Fig. 4.4 shows the power hyperbola as defi ned by the voltage and
current set. The HMP4030 (CH1 to CH3) resp. HMP4040 (CH1 to
CH4) can deliver a maximum power product of V · I = 160 W per
channel, e.g. to a maximum current of 6.67 A at 24 V.
In order to even better protect sensitive loads, the HMP series
instruments feature an electronic fuse. The FUSE button
allows to set and reset the electronic fuse. If the electronic fuse
was selected for one or several channels, the associated fuse
LED will light up white until the adjustment will be completed.
After the adjustment was completed the setting will be stored. If
the electronic fuse was activated for any channel, the channel's
LED will change to blue; after the fuse was reset it will return to
green. FUSE status is displayed for each selected channel (see
the following picture).
Fig. 4.5: Display of FUSE for each channel

4.5 Activation of channels

All HAMEG power supplies allow to turn the outputs on/off by
pressing an OUPUT button
on. Thus the output voltages and currents can be adjusted before
they are applied to the loads by pressing the OUPUT button
If the button is activated it will light up white.
The linear regulators incorporated require a certain amount
of capacitance in order to reach the levels of performance
( noise, ripple) specifi ed. Considerable technical effort (current
sink) was taken in order to reduce the capacitance in parallel
with the load. Please be sure to switch the output off before
connecting the load thus preventing excessive currents. When
switching on now the voltage resp. the current will show an
optimum response. Sensitive semiconductors such as laser
diodes should only be operated according to their manufactu-
rers' instructions.
5
3 . After an adjustment was completed
9 again for storing it; if this is not
. The power supply remains turned
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Subject to change without notice
13
.
19
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