Waveforms of Therapeutic Currents

Original Editor - Rafet Irmak

Top Contributors - Admin, Rafet Irmak, Rachael Lowe and Kim Jackson

Waveforms of Therapeutic Currents[edit | edit source]

Therapeutic currents are, special electric currents that are applied to human body for healing the body. Generally these are defined by using voltage-time chart of the current which can be seen in the oscilloscope screen. This page summaries the waveform of common therapeutic currents[1].

Fundamental Terms[edit | edit source]

Oscilloscope[edit | edit source]

An ossiloscope is an instrument which is used to observe voltage changes during time in electric circuits.

Signal Generator[edit | edit source]

A signal generator is an instrument which generates electrical signals at given waveform, frequency and amplitude. Electrotherapy equipment is a kind of signal generator which generates therapeutic signal waveforms in safe frequency and amplitude.

Figure 1: Ossiloscope and signal generator

Frequency[edit | edit source]

Frequency is a term which describes how many times a waveform repeat it self per second by signal generator.

A 100 Hz Sine Wave[edit | edit source]

Figure 2: Signal generator settings for sine wave at 100 Hz frequency and 1V peak amplitude.
Figure 3: Ossiloscope screen shot for sine wave at 100 Hz frequency and 1V peak amplitude.

A 500 Hz Sine Wave[edit | edit source]

Figure 4: Signal generator settings for sine wave at 500 Hz frequency and 1V peak amplitude
Figure 5: Osiloscope screen shot for sine wave at 500 Hz frequency and 1V peak voltage amplitude.

A 1000 Hz Sine Wave[edit | edit source]

Figure 6: Signal generator site for sine wave at 1000 Hz frequency and 1V peak amplitude
Figure 7: Osciloscope screen shot for sine wave at 1000 Hz frequency and 1V peak voltage amplitude.

Peak Amplitude[edit | edit source]

The term peak amplitude defines the highest positive or negative value of a waveform. In therapeutic currents peak amplitude generally defines the highest value of the voltage during time.

Peak to Peak Amplitude[edit | edit source]

The term peak to peak amplitude defines the amplitude between the highest negative to highest positive value. Peak to peak amplitude of a sine wave is equal to two times peak value of a sine wave.

Mean Amplitude[edit | edit source]

The term mean amplitude defines mean value of a waveform. In therapeutic currents mean amplitude is a quantity in terms of voltage. Peak amplitude of a sine wave has different mean amplitude value. Mean amplitude of a sine wave is equal to 0.637 x Peak Amplitude.

Peak and Mean Amplitude of 100 Hz and 1 Volt Sine Wave[edit | edit source]

Figure 8: Signal generator parameters for a sine wave at 100 Hz and 1V.
Figure 9: Osciloscope screen shot for peak and mean amplitudes of a 100 Hz 1 Volt sine wave.

Peak and Mean Amplitude of 1000 Hz (1KHz) and 10 Volt Sine Wave

Figure 10: Signal generator parameters for a sine wave at 100 Hz and 10 V.
Figure 11: Osciloscope screen shot for peak and mean amplitute of a 100 Hz, 10V sine wave.

Peak and Mean Amplitude of 1000 Hz (1KHz) and 20 Volt Sine Wave

Figure 12: Signal generator parameters for Peak and mean amplitude of a sine wave  at 100 Hz  and 20V.
Figure 13: Osciloscope screen shot for peak and mean amplitute of a 100 Hz, 20V sine wave.

Square Waveform[edit | edit source]

Square waveform is a common therapeutic waveform. Interrupted galvanic current and TENS are forms of Square waveform. The main parameter of a square waveform is duty cycle. It defines the time ratio when voltage is higher or lower then zero and when voltage is equivalent to zero.

50% Duty Cycle Square Waveform[edit | edit source]

Figure 14: Signal genrator settings for 10 V, %50 duty cycle, square waveform
Figure 15:  Osciloscope screen shot for 10 V, 50% duty cycle, square wave

20% Duty Cycle Square Waveform[edit | edit source]

Figure:16 Signal generator settings for 10 V, 20% duty cycle, square waveform
Figure 17:Osciloscope screen shot for 10 V, 20% duty cycle, square wave

50% Duty Cycle Square Waveform

Figure 18: Signal generator settings for 1 V, 100 Hz 50% duty cyle, square waveform
Figure 19: Osciloscope screen shot for 1V, 100 Hz, 50% duty cycle, square waveform

75% Duty Cycle Square Waveform

Figure 20: Signal generator settings for 1 V, 75% duty cycle, square wave form
Figure 21: Osciloscope screen shot for 1V, 100Hz, 75% duty cyclesquarewaveform

References[edit | edit source]