Avtech AVO-6-B, Instructions Manual

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Alternatively, a fast current probe may be used to monitor the current waveform.
Factory testing is conducted using a Tektronix CT2 or Pearson 2878 current
transformer. (This technique tends to introduce less waveform distortion than the
sensing resistor method. However, AC-couped current probes such as the CT2 will not
be able to operate at pulse widths of more than a few microseconds. The 2878 does
operate to 50 us, the maximum pulse width of the AVO-6HZ-B.)
MONITOR OPTION
Instruments with the -M option will have a monitor output on the mainframe, as shown
above. When a 50Ω load is connected to this output, the monitor voltage will be one-
tenth of the voltage present at the five module signal inputs. This output may be used to
monitor the voltage amplitude non-invasively.
The monitor output may be left unconnected if unused.
LENZ’S LAW AND INDUCTIVE VOLTAGE SPIKES
This instrument is designed to pulse resistive and diode loads and will exhibit a large
output spike when used to drive a load with significant inductance (as predicted by
LENZ'S LAW). For this reason the load should be connected to the output using low
inductance leads (as short as possible).
The voltage developed across an inductance L (in Henries), when the current is
changing at a rate given by dI
LOAD
/ dt (in Amps/sec), is: V
SPIKE
= L dI
LOAD
/ dt.
BASIC TEST ARRANGEMENT - WITHOUT OUTPUT MODULE
The AVO-6HZ-B can be tested initially without the supplied output module. If the output
module is not used, the mainframe output generates up to 110 Volts, into a five
separate 50 Ohm loads, as illustrated below:
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