Enraf Nonius 1600905, User Manual

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1600751-4D
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.
Surge Program can be used to adjust repeated sequences of contraction and rest periods. See
paragraph 11.2.11.a6 for details.
4.3.4 Russian Stimulation
This current type is an intermittent alternating current with a carrier frequency around 2500 Hz.
See fig 13.3 for the current waveform. Russian Stimulation was first used by Kots, a lecturer in
sports medicine at the Moscow State Acadamy. Kots used it for muscle strengthening in
prosthesiology and in the training of Russian cosmonauts. With this technique the electro
stimulation is applied both to individual muscles and to groups (either directly or via the nerve).
In direct stimulation, a frequency of 2500 Hz was found to produce the greatest contraction,
while the optimum frequency in indirect stimulation was 1000 Hz.
A specific feature of this type of muscle stimulation is that the alternating current is interrupted
50 times per second. This results in a pulse train, compa
rable to the ‘burst’ i n TENS. The total
duration of the pulse train is 20ms, giving a phase duration/phase interval ratio of 1:1. Kots uses
a Burst frequency of 50 Hz, approximately in the middle of the frequency spectrum used to
produce tetanic contraction (40-80 Hz). In addition to the 1:1 ratio, Kots also describes a phase
duration/phase interval ratio of 1:5.
The amplitude should be increased until a powerful contraction is produced (from the motor
stimulation level up to the limit of tolerance). As with all muscle stimulation applications a Surge
program can be used, allowing the muscles to rest between exercise cycles.
Parameters:
Carrier Frequency , expressed in kHz, is the base frequency of the alternating current.
Burst Frequency
, expressed in Hz, defines the repetition rate of the bursts.
Burst / Interval Ratio , defines the ratio of the burst length to the interval between the bursts.
The sum of the burst and interval duration is the reciprocal of the burst frequency i.e. with a
burst frequency set at 50 Hz and a burst / interval ratio of 1:5, the burst duration will be 20 * 1/6
= 3.3ms and the interval duration will be 20 * 5/6 = 16.7ms.
Surge Program can be used to adjust repeated sequences of contraction and rest periods. See
paragraph 11.2.11.a for details.
4.3.5 Micro Current
Micro Current is a monophasic rectangular waveform with manually selectable or alternating
polarity. See fig 13.4 for a graphical representation. Many therapists prefer Micro Current
therapy because of the low current amplitudes used. Alternating polarity can be used to average
out the DC component, thereby reducing the formation of electrolysis by-products.
Parameters:
Frequency , expressed in Hz, is the number of cycles delivered per second.
Alternation mode defines whether the polarity of the wave is automatically alternating or not.
Alternation Sequence , expressed in s, defines the polarity reversal timing in the alternating
mode.
Surge Program can be used to adjust repeated sequences of contraction and rest periods. See
paragraph 11.2.11.a for details. Surge programs are only available in the non alternating mode.