basic principles of electricity electromagnetic spectrum b electrical stimulating currents...
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Basic Principles of Basic Principles of ElectricityElectricity
ElectromagneticElectromagneticSpectrumSpectrum
Electrical Stimulating CurrentsElectrical Stimulating CurrentsCommercial Radio and TelevisionCommercial Radio and Television
Shortwave DiathermyShortwave DiathermyMicrowave DiathermyMicrowave Diathermy
InfrareInfrareddLASERLASER
Visible LightVisible Light
UltravioletUltraviolet
Ionizing RadiationIonizing Radiation
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LongestLongestWavelengthWavelength
ShortestShortestWavelengthWavelength
LowestLowestFrequencyFrequency
HighestHighestFrequencyFrequency
ElectronsElectrons
Particles Of Matter Possessing A Particles Of Matter Possessing A Negative Charge And A Small MassNegative Charge And A Small Mass
Net Movement Of Electrons Is An Net Movement Of Electrons Is An Electrical CurrentElectrical Current
Movement Of Electrons Is Like A Movement Of Electrons Is Like A Domino ReactionDomino Reaction
Electrons Will Move From Higher To Electrons Will Move From Higher To Lower PotentialLower Potential
AmpereAmpere
Unit Of Measure Which Indicates Unit Of Measure Which Indicates Rate At Which Electrons FlowRate At Which Electrons Flow• 1 amp = movement of 1 coulomb or 1 amp = movement of 1 coulomb or
6.25x106.25x101818 electrons /sec electrons /sec Current Flow Is In Milliamps Current Flow Is In Milliamps
(1/1000) Or Microamps (1/1000) Or Microamps (1/1,000,000)(1/1,000,000)
Electrical Potential Electrical Potential DifferenceDifference
Difference In Concentration of Difference In Concentration of Electrons Between Two PointsElectrons Between Two Points
Electrons Will Not Move Unless A Electrons Will Not Move Unless A Potential Difference ExistsPotential Difference Exists
VoltVolt
Creates The Potential DifferenceCreates The Potential Difference The Electromotive Force Which The Electromotive Force Which
Must Be Applied To Create Flow Of Must Be Applied To Create Flow Of ElectronsElectrons
Commercial Current Is 120 V or Commercial Current Is 120 V or 220 V220 V
ConductorsConductors
Materials That Permit Free Movement Materials That Permit Free Movement of Electrons of Electrons
Composed Of Large Numbers of Free Composed Of Large Numbers of Free ElectronsElectrons
Offer Little Resistance To Current FlowOffer Little Resistance To Current Flow Good ConductorsGood Conductors
• Metals (copper, gold, silver, aluminum)Metals (copper, gold, silver, aluminum)• Electrolyte SolutionsElectrolyte Solutions
InsulatorsInsulators
Materials That Resist The Flow Of Materials That Resist The Flow Of ElectronsElectrons
Contain Few Free ElectronsContain Few Free Electrons Insulator MaterialsInsulator Materials
• Air, Wood, GlassAir, Wood, Glass
Resistance = Electrical Resistance = Electrical ImpedanceImpedance
Opposition To Flow Of Electrical Opposition To Flow Of Electrical CurrentCurrent
Measured In OhmsMeasured In Ohms Ohm’s LawOhm’s Law Current Flow= Current Flow=
Voltage Voltage ResistanceResistance
WattWatt
Measure of Electrical PowerMeasure of Electrical Power Watts = Volts X AmpsWatts = Volts X Amps Modalities Use Milliamps or Modalities Use Milliamps or
MicroampsMicroamps
Electrotherapeutic Electrotherapeutic CurrentsCurrents
Direct (DC) or MonophasicDirect (DC) or Monophasic• Flow of Electrons Always In Same DirectionFlow of Electrons Always In Same Direction• Sometimes Called GalvanicSometimes Called Galvanic
Electrotherapeutic CurrentElectrotherapeutic Current
Alternating (AC) or BiphasicAlternating (AC) or Biphasic• Flow of Electrons Changes DirectionFlow of Electrons Changes Direction
– Always Flows From Negative to Positive Pole Until Always Flows From Negative to Positive Pole Until Polarity Is ReversedPolarity Is Reversed
Electrotherapeutic Electrotherapeutic CurrentsCurrents
Pulsed or PolyphasicPulsed or Polyphasic• Pulses Grouped Together and InterruptedPulses Grouped Together and Interrupted
– Russian and Interferential CurrentsRussian and Interferential Currents
Electrical GeneratorsElectrical Generators
All Are Transcutaneous Electrical All Are Transcutaneous Electrical StimulatorsStimulators• Transcutaneous Electrical Nerve Transcutaneous Electrical Nerve
Stimulators Stimulators (TENS)(TENS)• Neuromuscular Electrical Stimulator Neuromuscular Electrical Stimulator
(NMES)(NMES) = Electrical Muscle Stimulator = Electrical Muscle Stimulator (EMS)(EMS)
• Microcurrent Electrical Nerve Stimulators Microcurrent Electrical Nerve Stimulators (MENS) (MENS) = Low Intensity Stimulators = Low Intensity Stimulators (LIS)(LIS)
Electrotherapeutic Electrotherapeutic CurrentsCurrents
No Relationship Between Type Of No Relationship Between Type Of Current Used To Power Generator and Current Used To Power Generator and Type Of Current Output To PatientType Of Current Output To Patient
Generators May Be Powered By AC or Generators May Be Powered By AC or DCDC• Batteries = DC between 1.5 and 9 VBatteries = DC between 1.5 and 9 V• Wall Outlet = AC at 120 or 220V at 60 HzWall Outlet = AC at 120 or 220V at 60 Hz
Waveform or PulseWaveform or Pulse
Pulse= Individual Pulse= Individual WaveformWaveform
Phases (Duration)Phases (Duration) Interpulse IntervalInterpulse Interval Direction (Polarity)Direction (Polarity) AmplitudeAmplitude Rate Of RiseRate Of Rise Rate of DecayRate of Decay
• AccommodationAccommodation
Symmetrical WaveformsSymmetrical Waveforms
SineSine SquareSquare TriangulTriangul
arar
Symmetrical WaveformsSymmetrical Waveforms
Twin Peaked Twin Peaked Triangular Triangular WaveformWaveform• Found on Most High Found on Most High
Volt GeneratorsVolt Generators
Asymmetric WaveformsAsymmetric Waveforms
FaradicFaradic ExponentialExponential
• SawtoothSawtooth
Current ModulationCurrent Modulation
ContinuousContinuous InterruptedInterrupted BurstBurst
• PacketsPackets• Pulse TrainsPulse Trains• BeatsBeats
Ramped (Surge)Ramped (Surge)
Pulse AmplitudePulse Amplitude
Same As Intensity or VoltageSame As Intensity or Voltage Measured In Milliamps or MicrovoltsMeasured In Milliamps or Microvolts Average Current Determined By Average Current Determined By
Interpulse Interval Or Current DurationInterpulse Interval Or Current Duration
Pulse DurationPulse Duration
Length Of Time Current Is FlowingLength Of Time Current Is Flowing With Monophasic Current Phase Duration With Monophasic Current Phase Duration
Is the Same As Pulse DurationIs the Same As Pulse Duration With Biphasic Current Pulse Duration Is With Biphasic Current Pulse Duration Is
Determined By The Combined Phase Determined By The Combined Phase DurationsDurations
With Polyphasic Current The Combined With Polyphasic Current The Combined Pulse Duration And Interpulse Interval Is Pulse Duration And Interpulse Interval Is The Pulse PeriodThe Pulse Period
Pulse Frequency (CPS, Pulse Frequency (CPS, PPS, Hz) PPS, Hz)
Effects The Type Of Muscle ContractionEffects The Type Of Muscle Contraction Effects The Mechanism of Pain Effects The Mechanism of Pain
ModulationModulation
Electrical CircuitsElectrical Circuits
Path of Current From Power Source Path of Current From Power Source Through Various Components Back Through Various Components Back To GeneratorTo Generator
Power Source-Conducting Medium Power Source-Conducting Medium - Component Resistors - Component Resistors • Series CircuitSeries Circuit• Parallel CircuitParallel Circuit
Series CircuitSeries Circuit
One Path For Current To TakeOne Path For Current To Take Component Resistors Placed End To EndComponent Resistors Placed End To End Total Resistance = Sum of ResistancesTotal Resistance = Sum of Resistances Total Voltage = Sum of Voltage DecreasesTotal Voltage = Sum of Voltage Decreases
Parallel CircuitParallel Circuit
Component Resistors Placed Side to Side With Component Resistors Placed Side to Side With Ends ConnectedEnds Connected
Current Chooses Path With Least ResistanceCurrent Chooses Path With Least Resistance Resistors Have Lower Resistance But Higher Resistors Have Lower Resistance But Higher
Current Flow Than A Series CircuitCurrent Flow Than A Series Circuit
Current Flow Through Current Flow Through Biologic TissuesBiologic Tissues
Combination Of Both Series And Parallel Combination Of Both Series And Parallel CircuitsCircuits
Tissue Highest In Water And Ion Content Best Tissue Highest In Water And Ion Content Best Conductors - Blood, Nerve, Muscle, Tendon, Conductors - Blood, Nerve, Muscle, Tendon, Skin, Fat, BoneSkin, Fat, Bone
Safety In Using Electrical Safety In Using Electrical EquipmentEquipment
Ground Fault InterruptorsGround Fault Interruptors
Constantly compare amount of electricity flowing from wall outlet to whirlpool turbine with the amount returning
GFI will interrupt current flow in as little as 1/40 of a second
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