ALL-TEST PRO ATPOL II, Руководство пользователя

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19
Measuring Currents Below the Range of the Current Probe
A problem with measuring smaller currents arises when the current to be measured is below the range
of the current probe. In such cases, the current may not be read or the reading may be inaccurate. In
addition, any waveforms that are captured will have excessive noise on them.
If you are using a flexible current probe, you can simply wrap it around the conductor twice in order to
double the magnetic field strength. This can get it in the measurement range and it boosts the signal to
noise ratio. If you use this method, set the input ratio for the current probe to 1 : 2 (see the
Changing
Input Ratios in ATPOL II section).
If the current to be measured is small, it may be acceptable to open the circuit
and insert an extra length of wire that is wound up into a coil of 10 turns.
Clamping your current probe around this extension coil will boost the signal
strength 10 times and allow accurate reading of small currents. If you use this
method, set the input ratio for the current probe to 1 : 10 (or however many
turns there are in the coil).