galvanic currents
TRANSCRIPT
Galvanic CurrentsGalvanic Currents
Dr.Deepak Anap,Asso. Professor
COPT,PDVVPF
Galvanic Currents - Dr.Deepak
Objectives • History
• Introduction to DC
• Graphical Representation
• Interrupted DC
• Wave form Characteristics – Duration and Frequency
• IDC Waveforms
Galvanic Currents - Dr.Deepak
History
• Luigi Galvani ,an Italian Physiologist-on whose honor galvanic current is named.
• First to show that when electric current is passed through the legs of a frog, it twitched, way back in 1791.
Galvanic Currents - Dr.Deepak
Galvanic Currents - Dr.Deepak
Definition
• In DC, electrical current flows in one constant direction, as opposed to AC, in which the current constantly reverses direction.
• Ex of a device that provides DC : battery. • DC ultimately supplies power to nearly all
electronic devices (even if these devices require a component to convert AC current into DC current).
Galvanic Currents - Dr.Deepak
DC Vs AC
Galvanic Currents - Dr.Deepak
Galvanic Currents - Dr.Deepak
Modifications of DC
• Interruption – most usual modification of DC
• Interrupted DC
• Current flow commencing & ceasing at
regular intervals
Galvanic Currents - Dr.Deepak
Wave form Characteristics
• Duration
• Duration 100,300,600ms used for Treatment with IDC
Galvanic Currents - Dr.Deepak
Duration
• Frequency: No. of impulses/Sec• Depends on duration of Interval between the
impulses• Duration α 1/Frequency
Galvanic Currents - Dr.Deepak
Duration of interval
Galvanic Currents - Dr.Deepak
IDC waveforms
Galvanic Currents - Dr.Deepak
DC
Rectangular IDC
Current rises suddenly, constantly maintained for the duration of the stimulus then turned off abruptly
Triangular Pulses
• Traingular: has an equal phase of slow rise and then slow falling off in intensity
Galvanic Currents - Dr.Deepak
Trapezoidal Pulses
Current rises slowly, plateaus for a short period then gradually declines
Galvanic Currents - Dr.Deepak
Saw Tooth Pulses
current is gradually raised then turned off abruptly
Galvanic Currents - Dr.Deepak
Depolarised Wave Form
• Current of low intensity flows in reverse direction
• Chemical formation because of DC is reduced
Galvanic Currents - Dr.Deepak
Thank you