Constant Power Mode; Load Surge Capability - Chroma 63200 Series Operation & Programming Manual

High Power DC Electronic Load 63200 Series Operation & Programming Manual

3.5.4 Constant Power Mode

In CP mode, the current will be loaded by the programmed power. This mode is operated
under the F/W calculation. That is, take the measured V data, divide the Power setting and
get the I setting value. High frequency parts will be removed as there is a lower pass filter for
the measuring data.
Power can be programmed in either of low range or high range by the RANGE key. The low
power range is operated under low current range mode while the high power range is under
high current range mode.
There are two power levels (A or B) for CP function as other modes. Both A and B states
use the same range. You can select CPLA or CPLB using A/B key. Slew rate determines
the rate that the load level changes from one state to another.

3.5.5 Load Surge Capability

Chroma's 63200 Series DC Loads provide a unique load surge simulation capability, which
allows users to overdrive the loads up to 2.7 times their rated power for short periods. This
feature is ideal when the average power require by the UUT is low compared to short-term
peak power demands. Plasma Display Panel (PDPs) testing is one typical application,
others include battery 3C discharge, breaker & fuse over rating (300% to 1000%) tests, car
engine startup simulation and DC motor startup simulation.
The amount of surge loading available using the 63200 loads is related to the initial loading
conditions. Figure 3-12 and Figure 3-13 show the relationship of initial state (Load_Low under
Dynamic mode) and the maximum acceptable overdrive power.
Under this operation, the load will display an Over Power Protection Alarm (OPP) and will
disable the load current if the user violates the maximum load surge capability showed in the
figures below.
3-10
I
Load
Current
Input Voltage
Figure 3-11 Constant Power Mode
Power setting
P = V * I
V