Norsonic nor1217 Manual de usuario
INSTRUCTION
MANUAL
Outdoor microphone
nor1217
Outdoor microphone
nor1217
Nor1217 – User Guide
Im1217_1Ed1R1En – November 2013 edition
Norsonic is a registered trademark of Norsonic AS.
Every effort has been made to supply complete and ac-
curate information. However, Norsonic AS assumes no
responsibility for the use of – or for the consequential dam-
age resulting from the use of – this information and/or the
instrumentation described herein. Furthermore, Norsonic AS
assumes no responsibility for any infringement of the intel-
lectual property rights of third parties, wherever applicable,
which could result from such use.
Norsonic AS reserves the right to amend any of the informa-
tion given in this manual in order to take account of new
developments.
If you wish to communicate with us, please feel welcome
Our address is:
Norsonic AS, P.O. Box 24, N-3421 Lierskogen Norway,
Find us on the web: www.norsonic.com
Tel: +47 3285 8900
Fax: +47 3285 2208
E-mail: [email protected]
Copyright © Norsonic AS 2013
All rights reserved
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Norsonic Nor1217
Instruction Manual
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Contents
Chapter 1 Introduction ......................................................................................................... 1
Chapter 2 Assembling .......................................................................................................... 2
Grounding and lightning protection 3
Chapter 3 Microphone calibration....................................................................................... 4
Chapter 4 Technical description.......................................................................................... 5
Electrical description 6
System check 7
Frequency response 9
Self-noise 10
Cables and cable length 11
Directional response 12
Frequency response 13
Self-noise and wind 14
Chapter 5 Connecting the Nor1217 to Sound Analyser Nor140...............................................15
Chapter 6 Maintenance........................................................................................................17
Chapter 7 Specifications .....................................................................................................18
Mounting direction 18
Acoustic performance 18
General 18
Frequency response 18
Directional response 18
General 18
Conformity 19
Protection provided by the enclose 19
Accessories and spare parts 19
1
Norsonic Nor1217
Instruction Manual
1
Introduction
The outdoor microphone Nor1217 is a measurement
microphone protection kit for all-weather conditions. It
is mainly intended for temporary outdoor applications.
The microphone contains elements for protecting the
microphone cartridge from rain, snow, dust and insects,
satisfying IP 55 requirements. The Protection kit is
designed for use with the preamplifier Nor1209 and one
of the microphones Nor1225 or Nor1227.
Further, compared to a standard measurement micro-
phone, the Nor1217 improves the measurement accu-
racy by reducing the wind noise and by improving the
directional response for sound from different directions.
Combined with a suitable sound level meter including
a frequency response correcting function, the Nor1217
satisfy Class 1 specification requirements according to
IEC61672-1 and similar national standards for a sound
level meter class 1.
The microphone is intended for vertical mounting only
since the act of gravitation forms a part of the rain pro-
tection system. The reference direction may, however,
be selected to be vertical or horizontal based on the
applied frequency response compensation in the sound
level meter.
The outdoor microphone may be calibrated with a
normal sound calibrator suitable for ½” working stand-
ard microphones (WS2) and without the need for extra
accessories. Access to the microphone cartridge is
easily gained by dismounting the upper part of the
outdoor microphone.
The base of the Nor1217 is made of an electrical insulat-
ing material. The microphone body will be fully insulated
from the mounting mast thereby reducing pick-up of
electrical hum and noise.
The preamplifier Nor1209 used in the Nor1217 kit is
equipped with the standard 7-pin Lemo connector for
microphone preamplifiers. For verification of proper
operation, the preamplifier is equipped with a system
check facility, where an electrical signal applied on one
of the terminals are returned after passing through the
complete signal chain, thus verifying proper operation
of the microphone cartridge, preamplifier and micro-
phone cable.
Nor1217 is mainly designed to be used with the Nor140
Sound Analyser. This instrument has the requested fre-
quency compensation and delivers the required current.
2Chapter 2
Assembling
Assembling
The outdoor microphone Nor1217 normally shipped
without preamplifier and microphone, since these parts
is normally taken from the Nor140 Sound Analyser.
Depending on the application, you will need a mast
or tripod for mounting the microphone system and
possibly devices for proper grounding and lightning
protection, see below.
We recommend cable type Nor1408A, which
comes in standard lengths of 5, 10, 15, 20, 30 and 50
metres – other lengths are available on request. This
cable is Teflon®-insulated and hence absorbs very lit-
tle water, which is very important in order to retain high
insulation in all weather conditions. The mantle is made
of polyurethane to ensure a robust cable, yet flexible at
low temperatures.
Birdspike
Wind, dust and
water protection
Upper part
Microphone cartridge
Microphone preamplifier
Nor1209
Base
Connector/cable
Optional tripod adaptor
with tension relief
O-ring
NOTE: You need to use the “A” version
of the 1408 cable (1408A). The cable
comes with a threaded female connec-
tor housing that fits to the 1209 preamp-
lifier lock nut. Older versions (not “A”) of the ca-
ble do not have this treads and will not fit into the
microphone kit. The rubber protection covering
the female connector housing must be removed
in order to fit into the microphone kit.
3
Norsonic Nor1217
Instruction Manual
Unscrew and remove the upper part consisting of
birdspike and windscreen as one unit. Do not remove the
windscreen from this upper part as this may destroy the
weather protection and alter the acoustic performance.
The unit is delivered with an adaptor for mounting
on a tripod. The cable is led through a slot in the side of
the adaptor. The base screw has a threaded hole like
those commonly used for cameras (3/8” UNC). The
base screw also forms a tension relief for the cable.
Remove the base screw and slide the cable through
the base unit. Assemble the microphone cartridge to
the preamplifier and connect the preamplifier to the
cable. We recommend to mount the supplied O-ring
between the microphone cartridge and the preamp-
lifier. Screw the lock nut on the preamplifier onto the
female connector on the 1408A cable. Push the pre-
amplifier carefully into the base unit. The preamplifier
and microphone is aligned in the correct position by
a spring force. After mounting the upper protection
part, the outdoor microphone unit will be ready for use.
However, we recommend that you test the unit togeth-
er with the measuring instrument by applying a calibra-
tor before the upper part is mounted.
Grounding and lightning protection
If the outdoor microphone assembly is the highest ob-
ject in the vicinity when mounted, it may be exposed
to lightning strokes. We recommend to use a conduc-
tivemast and to ground it properly. A rod in proper con-
tact with the conductive mast should be made at the
side and 50 cm above the tip of the microphone. The
rod should be placed at least 25 cm to the side of the
microphone assembly and have a diameter not more
than 10 mm in order not to interfere with the directional
properties of the microphone.
Safety considerations may require the screen of the
microphone cable to be properly grounded and that
the internal conductors are clamped for high voltage
protection.
We recommend making the combined grounding
for the cable and instrument at one point only in order
to reduce the risk of pick-up of hum and electromag-
netic noise.
Verify the noise floor of the complete system after
installation is completed to ensure it is below the lower
end of the required measurement range. If a quiet lo-
cation is not available, the noise floor may be meas-
ured by substituting the microphone with a dummy mi-
crophone like Nor1448. As an alternative the Nor1447
adaptor terminated with a short-circuit or a 50 ohm
BNC termination is also a suitable device for making
this test. A sound calibrator in OFF-mode may also be
used to attenuate the external noise. A ½” microphone
normally requiring polarization voltage may also be
used without polarization voltage. It will then have a
very low sensitivity.
NOTE: Please note that the System
Check signal must be deactivated when
you want to calibrate the microphone with
an acoustical calibrator. Unless deacti-
vated, you will read unstable values due to the
interference between the System Check signal
and the signal from the sound calibrator.
4Chapter 3
Microphone calibration
Microphone calibration
The Nor1217 can be calibrated with a sound calibra-
tor for ½” microphones without the need for special
couplers. We recommend using Nor1251 (1000 Hz) or
Nor1253 (250 Hz).
Unscrew the upper part of the microphone to gain
access to the microphone cartridge. Mount the cali-
brator slowly and carefully while turning the calibrator
and switch it on. See figure.
If the calibrator frequency is 250 Hz, adjust the
reading to be the level stated for the calibrator, e.g.
124,0 dB for Nor1253 with 124 dB specified level.
If the calibrator frequency is 1000 Hz, adjust the
reading to be 0,1 dB below the stated calibrator level,
e.g. 113,9 dB for Nor1251 calibrator with a stated level
of 114 dB.
This is only valid if the frequency response correc-
tion is turned off. For the Nor140 the frequency cor-
rection is turned off, when entering into the calibration
menu. Perform calibration and calibrate the micro-
phone as a normal free field microphone. I.E. -0.1 dB
if using a 1000 Hz calibrator. When leaving the cali-
bration menu, you will observe that the level measured
with the calibrator on, is different from what obtained
in the calibration mode. This is correct, and is due to
the frequency correction added. If horizontal position
is selected, the signal will be about 0.1 dB higher than
the calibrated signal, in vertical position the signal will
be 0.3 dB lower than the calibrated level. This does
not apply if you calibrate with a 250 Hz calibrator since
there is no correction added at this frequency.
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