Local Operation
3-15
3.6
AC Load Simulation -- Constant Current Mode
Figure 3-7 Constant Current Mode
In CC mode, the Load will sink a current according to the programmed value if the input
voltage is higher than the minimum operating voltage. The CC mode can be set by pressing
CC
key in the front panel.
The waveform of the current is programmed as a sinusoidal wave synchronized by the
zero-crossing waveform of the input voltage. The PF can be set between
±
1. The positive PF
value means that the voltage lags the current, and the negative PF value means that the
voltage leads the current. That is, the peak voltage occurs before the peak current for a
negative PF. On the other hand, the peak voltage occurs after the peak current under the
positive PF.
To set the condition of the CC mode, press the arrow key to select the setting parameters on
the LCD display, including current RMS value, PF, CF, I
p
(max). The setting values are
restricted that the input voltage is sine waveform or quasi-sine waveform. A limitation exists
between PF and CF. If the waveform of the input voltage is a square wave, a special setting is
prepared in
RLC/DC RECT
. See
Section 3.9
CF & PF parameters have CF ONLY, PF ONLY and BOTH, these three types in CC mode.
If CF only is set, the PF should remain at the CF maximum and cannot be changed. If PF only
is set, the CF should remain at the PF minimum and cannot be changed. If BOTH is set, it is
necessary to set priority. When CF is set as the priority, the range of PF that can be set is
limited to the PF range allowed for the CF value set (according to the
). On the
contrary, if PF is set as the priority, the range of CF is limited to the CF range allowed for the
PF value set (according to
If the voltage is drawn to 0V under CP mode, it will trigger the warning of
Load Fail (LDF). Meanwhile, the loading for the load will be stopped.
When LDF warning is triggered then press power switch to restart AC
load. If AC load can not function normally after restarting, please contact
Chroma sales or service office.
The output voltage of UUT will distort because of loading current. If the
output voltage of the UUT becomes distortion and drops below 10V due to
the loading, the AC load will stop the loading.
WARNING
I current setting
Load
Current
V
Input Voltage
