Enraf Nonius 1600905, Руководство пользователя

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1600751-4D
Parameters:
Carrier frequency
, expressed in kHz, is the base frequency of the alternating current.
Beat frequency,
expressed in Hz, defines the channel frequency difference in classical
interferential mode and the rate at which the amplitude is internally modulated in the vector
modes.
Frequency Modulation , expressed in Hz, defines a variable frequency range that is summed to
the Beat frequency i.e when the Beat frequency is set to 80 Hz and the Frequency modulation is
set to 40 Hz, the final frequency will vary from 80
– 120 Hz. Frequency modulation is often used
to prevent accommodation to stimulation or to improve patient tolerance.
Modulation Program defines the time and sequence in which the frequency will sweep through
the Frequency modulation range. See for the available Modulation programs fig 13.11 – 13.11.3.
Balance defines the difference in current amplitude between the two channels. Only available in
classical interferential mode.
Vector position adjustment defines the angle of the dipole vector with respect to the position
of the electrodes.
Rotation Speed , expressed in s, defines the time elapsed during one revolution of the vector in
automatic dipole vector mode.
4.3.2 Biphasic Pulsed Currents (TENS)
4.3.2.a Asymmetrical and Alternating Asymmetrical
The asymmetrical biphasic pulsed current waveform is often used in TENS (Transcutaneous
Electrical Nerve Stimulation) applications. This waveform is characterized by variable phase
duration and variable pulse frequency. Its typical amplitude, duration, and rate of rise and decay
are unequal for each phase with respect to the baseline. The waveform is fully balanced, i.e. the
phase charges of each phase are equal. See fig 13.1 for a graphical representation.
A variation to the standard biphasic asymmetrical pulsed current is the alternating one, in which
the successive pulse phases alternate with respect to the baseline. See fig 13.1.2 for details.
This waveform is also fully balanced.
To prevent accommodation to stimulation or to improve patient tolerance, the pulse frequency
can be varied through frequency modulation. Several frequency modulation programs are
available. See fig 13.11
– 13.11.3 for details.
Parameters:
Phase Duration , expressed in µs, is the elapsed time from the beginning to the termination of
the initial pulse phase. See fig 13.1 for details.
Pulse Frequency , expressed in Hz or pps (pulses per second), defines the repetition rate of the
TENS pulses. See fig 13.1 for details.
Frequency Modulation , expressed in Hz, defines a variable frequency range that is summed to
the Pulse frequency i.e when the Pulse frequency is set to 80 Hz and the Frequency modulation
is set to 40 Hz, the final frequency will vary from 80
– 120 Hz.
Modulation Program, defines the time and sequence in which the frequency will sweep
through the Frequency modulation range. See for the available Modulation programs 13.11 –
13.11.3.