Neurotechnology Research Systems
© Plexon Inc
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Whenever the current monitor does not appear to match the requested stimulation pattern, the
voltage monitor should be examined. Refer to section 5.5, Verifying the output on an oscilloscope
and section 5.6, Compliance voltage and stimulation failure.
9.4
Impedance Test with an Open Circuit
Ideally, if no electrode is connected to the stimulator (or the connection to the electrode is broken)
then the impedance test procedure would indicate infinite impedance. However, due to stray
capacitance in the output of the stimulator and in the cabling to the electrode, the impedance test
procedure will yield a finite but large impedance result. With no cable connected to the stimulator,
this open circuit impedance will vary from channel to channel and will typically range from 5.5 M
to 11.5 M
With the 14-03-A-03 stimulation cable connected to the stimulator, but no electrodes
connected to the cable, the open circuit impedance will typically range from 1.5 M
to 5.75 M
9.5
Channel fails to start in Impedance Test mode
If you use the Start All command in Z test mode, occasionally one of the channels will fail to start. If
you observe that the voltage monitor output is a flat line at zero during impedance testing, then you
should change the channel to back to edit mode and then load and re-start the channel.
