Chroma 66203, Руководство пользователя

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Operation
4-39
3. If the load of CT secondary side is external instead of using the
shunt inside the 66203/66204, the CT and ExtSH function must be
enabled at the same time. The CT conversion ratio and external
resistance need to be set. The CT and EXT/SH indicators will be
turned on.
4. Since the sensing voltage amplitude is small, the measurement
cable should be as short as possible to avoid signal interference
and affecting the accuracy. It is suggested to use twisted or
coaxial cable for measurement.
WARNING
1. When CT is in use, it should keep the secondary side coil from open
as it will generate high voltage when the current is passing through
the secondary side coil and it will cause hazard.
2. When DC CT is in use, the power supply of secondary side should
use 1200Vrms or above for isolation to ensure the safety of usage.
When multiple DC CTs are used for different measurement
channels, the power supply of secondary side coil has to be isolated
for 1200Vrms.
ExtSH
Figure 4-60 EXTERNAL Setup Screen
If the maximum current of UUT exceeds the maximum range of the 66203/66204 Digital
Power Meter, it can select external shunt to work with the power meter for measurement.
It would need to enable the ExtSH function on the power meter and set the external shunt
resistance. The setting range is 0.0001m~99.999 and the unit is
Ω .
。
The UUT current will flow into the connected external shunt and the voltage input EXT
terminal (EXT, I-) sensed from the external shunt will be transformed into the actual
measured current by the power meter.
The figure below shows the wiring: