User Manual

Connecting signals
To connect a si
mple current transformer
To use a conventional current transformer (CT) like the Tektronix CL series (or any
other transducer with a current output), connect the normal AHI and ALO inputs
of the PA3000
to the outputs of the current transformer. Follow the manufacturer’s
instructions for the safe use and installation of the transducer. Depending on the
output level of the current transformer, you will need to choose between the 30 A
AHI input and the 1 A AHI input. The choice will be dependent on the dynamic
range of the output of the current transformer that you are expecting.
Normally the positive or HI output of the transducer will be marked with the
point of an arrow or a + symbol. Connect this terminal to the appropriate AHI
input of the PA3000.
Figure 18: Current transformer connections
Current scaling
A current transformer produces an output current that is proportional to the load
current being measured. For example, the Tektronix CL200 produces an output
current that is 1/100 of the current being measured.
To measure the correct current on the PA3000, use the scaling function of the
analyzer to scale, or multiply, the CT output current.
For example, the CL200 is a 100:1 CT. When measuring 100 A, its output is 1 A.
To scale this on the PA3000, a scale factor of 100 must be entered:
Press
.
Select
Inputs and press .
Select
Scaling and press .
Select
Amps and press .
Use
to clear the entry.
Enter the new scale factor (100).
30 PA3000 Power Analyzer User Manual