APS 6RL Series, Руководство по эксплуатации

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6RL SERIES OPERATION MANUAL
SECTION 3: PRODUCT OVERVIEW
Entire Contents Copyright

2018 by Adaptive Power Systems, Inc. (APS) • All Rights Reserved • No reproduction without written authorization from APS.
6RL Series Regenerative DC Load Operation Manual Page 19 of 204
3.4.1.2 Minimum Voltage for Maximum Current
Due to technical reasons, all models in
this series have a minimum internal
resistance that requires the unit to be
provided with a minimum input voltage
(U
MIN
) in order to be able to draw the full
current (I
MAX
). This minimum input
voltage varies by model and is listed in
the technical specifications . If less
voltage than U
MIN
is supplied, the load
proportionally draws less current.
3.4.2 Constant Current (CC)
Mode
Current regulation is also known as current limitation or constant current mode (CC) and is
fundamental to the normal operation of an electronic load. The DC input current is held at a
predetermined level by varying the internal resistance according to Ohm’s law R = U / I such
that, based on the input voltage, a constant current flows. Once the current has reached the
adjusted value, the device automatically switches to constant current mode. However, if the
power consumption reaches the adjusted power level, the device will automatically switch
to power limitation and adjust the input current according to I
MAX
= P
SET
/ U
IN
, even if the
maximum current set value is higher. The current set value, as determined by the user, is
always and only an upper limit.
While the DC Input is switched on and constant current mode is active, the condition “CC
mode active” will be indicated on the graphic display by the abbreviation CC and this
message will be passed as a signal to the analog interface. It is also stored as a status
condition, which can be read as a status message via the digital interface.
3.4.3 Constant Power (CP) Mode
Power regulation, also known as power limitation or
Constant Power (CP), keeps the DC input power of the
device at the adjusted value, so that the current
flowing from the source, together with the input
voltage, achieves the desired value. Power limitation
then limits the input current according to I
IN
= P
SET
/
U
IN
as long as the power source is able to provide this
power.
Power limitation operates according to the auto-range
principle such that at lower input voltages higher
current can flow and vice versa, in order to maintain
constant power within the range PN (see diagram to
the right).