Cr Offset Error Compensation - Chroma 63200 Series Operation & Programming Manual

High Power DC Electronic Load 63200 Series Operation & Programming Manual
(4) When it is "LOAD ON", Von Point is not set to 0V and Von Protection is disabled, switch
the SW to on after it was turned off for a period of time and then turn it off again. The
current loading still goes on when there is no power, and overshoot may occur once the
SW is turned off with any power input as Figure 3-21 shows. It may damage the UUT and
the DC Load in this case.
V
UUT
Output
Von
I
Load Sink
Current
Setting
Figure 3-21 Von Point is not set to 0V without Protection

3.17 CR Offset Error Compensation

In CR mode the DC Load will follow the preprogrammed resistance to load the current to input
voltage by linear ratio, and the change of input voltage causes the load current to change. CR
compensation enables the input voltage of any kind to be accurate in CR mode. The
resistance may generate the different offset errors, which could be very big due to various
input voltage if there is no CR compensation.
CR Compensation:
(1) Advantage: The measurement in CR mode will be more accurate because of
compensation and the accuracy of 63200 Series is based on the compensated result.
(2) Disadvantage: Controlling current is the mechanism of compensation and in the process
of continuous compensation; the current will fluctuate until reaching stable state to get
accurate and stable current.
No CR Compensation:
(1) Advantage: The loading current will not fluctuate due to the compensation mechanism.
(2) Disadvantage: The reading in CR mode will be varied with voltage and same for the
accuracy.
Note The Model 63211 and 63212 do not support CR offset compensation.
3-20
t
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