GRAS 40BH Micrô 1/4" phân cực ngoài, áp suất cao

GRAS 40BH 1/4" Ext. Polarized Pressure Microphone, High Pressure

Part Number: 40BH

Category: GRAS Sound & Vibration

Status: Available

Freq range: 10 Hz to 20 kHz
Dyn range: 54 dB(A) to 193 dB
Sensitivity: 0.4 mV/Pa

Sale Price: Liên hệ

0903368648

+84903368648

1. Introduction

The 40BH is an IEC 61094 WS3P ¼" externally polarized high-pressure microphone with rear-venting.

40BH is a high-precision condenser microphone made according to IEC 61094-4 requirements. Its very low sensitivity and wide frequency response make it ideal for measuring very high sound pressure levels of up to 194 dB. It is extremely robust and reliable and can handle acoustic impulse measurements in frequencies of up to 20 kHz.

40BH is individually factory calibrated and delivered with a calibration chart stating its specific open-circuit sensitivity and pressure frequency response.

NOTE: At low frequencies, protection grids are acoustically transparent; however, around 20 kHz and above, protection grids can act as resonators and influence the frequency response. So for higher frequency measurements, ¼″ and ⅛″ microphones have been optimized for use without the protection grid. Please remove the protection grid when measuring.

2. Typical Applications and Use

40BH is typically used for sound pressure, very high level measurements, and impulse-sound measurements. It is suitable for general purpose acoustic measurements in couplers and at boundaries.

The 40BH is a very versatile microphone when connected to the RA0086 Transmitter Adapter for ¼" Microphones. The 40BH becomes a high-impedance sound source when the RA0086 takes a calibration signal directly from the signal generator and makes the microphone behave like an electrostatic loudspeaker. When used for calibrating an acoustic coupler, this gives a frequency response that is as good as when the 40BH behaves like a microphone.

3. Compatibility

The 40BI requires a standardized 1/2 or 1/4 inch LEMO preamplifier and an input module that supports this technology with a 7-pin LEMO connector.

4. System Verification

For daily verification and check of your measurement setup, we recommend using a calibrator like GRAS 42AG Multifunction Sound Calibrator.

For proper sensitivity calibration, we recommend using a pistonphone like GRAS 42AP Intelligent Pistonphone.

5. Specifications

Polarization/Connection	200 V / Traditional
Frequency range (±2 dB)	10Hz to 20kHz
Dynamic range	54dB (A) to 193dB
Open-circuit sensitivity @250Hz (±2 dB)	-68dB re 1V/Pa
Microphone cartridge capacitance, typ.	6pF
Microphone venting	Rear
IEC 61094-4 Compliance	WS3P
Temperature range, operation	-40 to 85 °C
Temperature range, storage	-40 to 150 °C
Static pressure coefficient @250Hz	-0.01dB/kPa
Humidity range non condensing	0 to 100 % RH
Humidity coefficient @250 Hz	-0.001dB/% RH
Temperature coefficient @250 Hz	-0.01dB/°C
CE/RoHS compliant/WEEE registered	Yes/Yes/Yes
Weight	1.5 g