External source of excitation
When working with the session-based interface, the ExcitationSource
property
indicates the source of ExcitationVoltage
for
bridge measurements or ExcitationCurrent
for
IEPE sensors and RTDs. Excitation source can be:
Internal
External
None
Unknown
By default, ExcitationSource
is set to Unknown
.
Change the excitation source of a microphone channel.
Create a session and add an analog input microphone
channel.
s = daq.createSession('ni'); ch = addAnalogInputChannel(s,'cDAQ1Mod3',0,'Microphone')
ch = Data acquisition analog input microphone channel 'ai0' on device 'cDAQ1Mod3': Sensitivity: 'Unknown' MaxSoundPressureLevel: 'Unknown' ExcitationCurrent: 0.004 ExcitationSource: Unknown Coupling: AC TerminalConfig: PseudoDifferential Range: -5.0 to +5.0 Volts Name: '' ID: 'ai0' Device: [1x1 daq.ni.CompactDAQModule] MeasurementType: 'Microphone' ADCTimingMode: ''
Change the excitation source value to 'Internal'
.
ch.ExcitationSource = 'Internal'
ch = Data acquisition analog input microphone channel 'ai0' on device 'cDAQ1Mod3': Sensitivity: 'Unknown' MaxSoundPressureLevel: 'Unknown' ExcitationCurrent: 0.004 ExcitationSource: Internal Coupling: AC TerminalConfig: PseudoDifferential Range: -5.0 to +5.0 Volts Name: '' ID: 'ai0' Device: [1x1 daq.ni.CompactDAQModule] MeasurementType: 'Microphone' ADCTimingMode: ''