BVRAMB Ambient Noise Microphone
Installation Instructions
2
BVRAMB issue 4
C O M M U N I C A T I O N S
1.2 BVRAMB A
MBIENT
N
OISE
M
ICROPHONE
S
PECIFICATIONS
Dimensions (H x W x D)
141mm x 81mm x 44mm
Weight
Approx 0.4Kg
Power requirements
Nominal 24V DC @ 20mA
Max no. BVRAMB per input
2
BVRD2M Attenuator Increase
/ Decrease time
For 10dB change For 20dB change
Fast
2 seconds 4 seconds
Medium
9 seconds 18 seconds
Slow
26 seconds 52 seconds
Output pre-set busy freeze detector
Sensitivity
-48dB
Release
1.6 seconds
Surveillance output with no
ambient noise
Minimum 250mV DC
Maximum output
Approx 13V DC
N
OTE
: All BVRAMB Ambient Noise Microphones are tested and Factory
Preset to ensure correct output levels are produced. It should not be
necessary to adjust any internal settings within the BVRAMB.
BVRAMB Sensitivity
(white noise source,
SPL 'A' weighting,
Slow response)
DC Output Voltage
(@ Factory Preset Sensitivity)
BVRAMB set to 'Medium' response
45dBA
0.29V
50dBA
0.35V
55dBA
0.45V
60dBA
0.65V
65dBA
1.02V
70dBA
1.77V
75dBA
3.10V
80dBA
6.1V
BVRAMB Response Timing
Time constant
Slow
Tc = 1 second
Medium
Tc = 0.5 second
Fast
Tc = 0.1 second
