BRUEL & KJAER 2671-W-001 Operation manual

PRODUCT DATA
CCLD Microphone Preamplifier Type 2671-W-001
CCLD Microphone Preamplifier Type 2671-W-001 enables you to
make acoustical measurements with a CCLD input module. You
can connect ½
″ prepolarized microphones to the preamplifier. The
preamplifier’s low output impedance allows problem-free use of
long extension cables. The robust, compact design means that you
can use Type 2671-W-001 over a wide range of environmental
conditions.
Uses
• Low price, multichannel sound measurement setups with
½″Brüel & Kjær prepolarized condenser microphones
• Multichannel signal analysis measurements
• Multichannel sound power measurements
• Industrial machinery noise measurements
Features
• Optimised noise specifications
•ICP
®compatible
• BNC connector for easy installation and use with inexpensive
BNC cables
• Connects directly to CCLD sockets and to LEMO sockets
with adaptor
• Low output impedance allows long extension cables to
be used
• Falcon Range®product
• Supports “Smart transducer Interface” IEEE 1451.4 containing
TEDS (Transducer Electronic Data Sheet
Introduction
CCLD Microphone Preamplifier Type 2671-W-001 is very
compact and operates over a wide range of temperature,
humidity and other environmental conditions. It has a very high
input impedance, presenting virtually no load to the microphone.
Its low output impedance means that you can connect long
cables between the preamplifier and measurement equipment.
Description
CCLD products operate on a constant-current power supply and
give output signals in the form of voltage modulation on the
power supply line. One of the advantages of this is that you can
use inexpensive BNC coaxial cables.
The preamplifier converts the CCLD supply, which must be
between 2 and 20 mA (nominal 4 mA), into a constant 12 V DC
voltage level. The output signal from the microphone swings
around this DC level. Since no polarization voltage is available,
only prepolarized condenser microphones can be used. This
preamplifier is also available in a version with a 20 Hz high-pass
filter (Type 2671) and in a version with built-in A-weighting
(Type 2699).
TEDS
“Supports TEDS” means that the preamplifier can be used with
the Smart Transducer interface according to IEEE 1451.4. The
ability to store and recall TEDS data drastically reduces test
setup time and allows cost savings in most measurement
situations.

HEADQUARTERS: Brüel&Kjær Sound & Vibration Measurement A/S · DK-2850 Nærum · Denmark
Telephone: [phone] · Fax: [phone] · www.bksv.com · [e-mail]
Local representatives and service organisations worldwide
ËBP-2111---jÎ BP2111–12 2012-11
Specifications – CCLD Microphone Preamplifier
Type 2671-W-001
Unless otherwise specified, the data above are valid at 23°C and 4 mA supply,
cable length < 40 m and microphone capacitance = 12 pF
Ordering Information
Compliance with EMC Directive and Low Voltage Directive of the EU
Compliance with the EMC requirements of Australia and New Zealand
Specification Value
Frequency Response (re 250 Hz) 20 Hz to 50 kHz, ±0.2 dB
Lower –3 dB limit at <1.2 Hz
Upper –0.5 dB limit at >50 kHz
Attenuation –0.3 dB (typical)
Gain Matching 200 Hz to 10 kHz, 0.1 dB
Phase Linearity 1 kHz to 10 kHz, <±1°
20 Hz to 20 kHz, <–3°, +10°
Phase Matching 5°at 50 Hz
2°at 100 Hz
Input Impedance 10 GΩ|| <0.4 pF
Output Impedance <50Ω
Max. Output Current At 4 mA supply, 3 mA (peak)
At 20 mA supply, 19 mA (peak)
Max. Output Voltage 7 V peak for f<20 kHz
Corresponding to:
141 dB SPL for microphone sensitivity
of 30 mV/Pa
138 dB SPL for microphone sensitivity
of 50 mV/Pa
Max. DC Output Level 12 V ±2V
Distortion (THD) <–70 dB at 1.0 Vout, 1 kHz
<–60 dB at 1.0 Vout, 10 kHz
Output Slew Rate 2V/μs (typical)
Noise <3μV (typ. 2 μV) A-weighted
<5μV (typ. 4 μV) Lin., 22.4 Hz to 22.4 kHz
Start-up Time Signal within 0.1 dB within <60 s
Power Requirements CCLD supply, 2 to 20 mA. Nominal 4 mA
Connector Type BNC socket
Dimensions ∅12.7 mm ×85 mm (∅½″×3.3″)
(including connector)
Thread for Preamplifier Mounting 11.7 mm — 60 UNS
Temperature Range Operating: –20°C to +60°C
(–4°to +140°F)
Storage: –25°C to +70°C (–13°to +158°F)
Humidity 0 to 90% RH, non-condensing at
40°C (104°F)
Shock Max. 100 g
Influence of 80 A/m, 50 Hz
Magnetic Field Max. 4 μV
Cables
AO-0087-D-xxx*
*Cables are available in different lengths: xxx is the length in decimetres
Single-screen coaxial cable, BNC (M) to BNC (M)
Power Supply Adaptors
WB-1421 LEMO to BNC Adaptor
TRADEMARKS
ICP is a registered trademark of PCB Group Inc.
Brüel&Kjær reserves the right to change specifications and accessories without notice. © Brüel&Kjær. All rights reserved.