
MK:427 Environmental Noise Microphone
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Operation
External Connections
External connection to the MK:427 is made via the supplied 10m cable with the following wiring
connections:
Power Supply
Red & Orange:
Nom12VDC
Black & Green & Braid & Blue:
Power Ground (0V)
Notes:
The nominal power supply voltage is +12VDC.
The MK:427 can operate with a power supply within the range of +9VDC to +36VDC
The maximum current for normal operation is 75mA.
The power supply for the unit must be independent of the isolated loop circuit.
Isolated Loop circuit
White:
Loop output
Brown:
Loop input
Notes:
The nominal output current is 0.1mA/dB over the range of the instrument.
The maximum allowable loop voltage is 30V.
Actuator control
The electrostatic actuator is
Yellow:
Any voltage of b5V to +12V = Actuator on
Any voltage of between 0V to +0.3V = Actuator off
Green:
Ground (0V). Connect to power supply ground (0V)