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EN109-1498751-47 IFU
•
See paragraph
Vacuum electrodes
for the application of the vacuum electrodes.
•
When you use only one vacuum channel, close the other channel with one of the vacuum cables
not in use.
Electrolytic effects
Electrolysis occurs under the electrodes when current types with a DC component are applied.
Because the largest concentration of electrolytic by-products caused by ion migration occur under the
electrodes, we recommend the use of the supplied sponges to keep the effects to a minimum. Make
sure that the sponges are kept well moistened and place the thick side of the sponge between the
flexible rubber electrode and the patient.
Current density
In the particular standard for Electrical Nerve and Muscle Stimulators, IEC 60601-2-10, it is
recommended not to exceed a current density of 2 mA r.m.s. / cm², otherwise skin irritations or
etching can occur. For current types that contain a DC component we recommend not to exceed a
current density of 0.2 mA / cm².
To find the maximum recommended current amplitude in mA for the Interferential, Premodulated and
Russian Stimulation current waveforms, multiply the electrode surface in cm² by two. For all other
current waveforms, the stimulator output current can never exceed 50 mA r.m.s. This implies that with
an electrode surface of 25 cm² the current density can never exceed 2 mA r.m.s. / cm². As a rule of
thumb for smaller electrodes, such as the 3.2mm self-adhesives, the maximum current setting
available on the stimulator for a given current waveform should proportionally be reduced.
For a precise calculation of the r.m.s. value of a pulsed current waveform the following formula can be
used:
𝐼
𝑅𝑀𝑆
= 𝐼
𝑝𝑒𝑎𝑘
√𝑝ℎ𝑎𝑠𝑒 𝑑𝑢𝑟𝑎𝑡𝑖𝑜𝑛 [
µ𝑠
] ∗ 𝑝𝑢𝑙𝑠𝑒 𝑓𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦 [𝐻𝑧] ∗ 10
6
For symmetrical TENS currents, the Phase duration should be multiplied by 2. The value of the peak
current
𝐼
𝑝𝑒𝑎𝑘
can be taken from the current display.
Electrodes should be placed with care, ensuring good electrical contact over the entire electrode
surface.
Connection and disconnection reactions
Constant Current (CC) output characteristics may cause unpleasant connection and disconnection
reactions if the electrodes are not securely placed or lose contact with the skin. Make sure the current
amplitude is set to 0 mA when you apply or remove the electrodes. Use the Constant Voltage (CV)
output mode with dynamic electrode applications.
Содержание 1498.901
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