natus Dantec Keypoint Focus - Maximum Current Density

Dantec Keypoint Focus
35
Maximum Current Density
Attention! If the current density exceeds 2 mA rms/cm
2
, it may require the special attention
of the user (the risk of burning the skin). The max. pulse current will depend on the frequency
of the stimulation, pulse width and the area of the electrode. The current density may be
calculated as follows:
______
J =
√
(f × Tp) × I/A,
where f designates the frequency of stimulation, Tp pulse width, I pulse current and A the
area of the electrode. In certain cases, however, e.g. nerve damage, it may be necessary to
apply heavier currents.
Electrode Areas
9031E017 = 0.58 cm
2
9013L036 = 0.39 cm
2
9013L069 = O × 0.5 cm
2
where O designates the circumference.
An example: 9013L036 surface stimulation electrode, felt tips, stimulus frequency 2 Hz, pulse
width 0.2 ms:
__________
J =
√
(2 × 0.0002) × I/0.39 cm
2
< 2 mA/cm
2
I < 39 mA