Model 30 Series Application Overview
Application Details and FAQ’s
Sonomètres Pulsar 
Lärmmessgeräte Pulsar Application Overview
for Model 30 Real Time Analyser
There are two variants of model 30, the Class 1 model 30 itself, and the class 2 variant 30-2. Both units are identical EXCEPT for the microphone system.
Both units are a combination of a REAL TIME ANALYSER (RTA) and Integrating-Averaging Sound Level Meter (ISLM). In the RTA role they measure 10 octaves bands in parallel, either displaying the data on screen or storing it in memory. As an ISLM, they can be configured to store either exponential sound level or Leq or even both, as well as the statistical values of Ln
The units are designed to meet the new IEC standard IEC 61672 and both designs have been Pattern Approved by an Official EU National laboratory.
Being among the most capable RTA and ISLM available on the market, the two variants of model 30, can fulfil almost any conventional noise measurement need.
Usage
The model 30 was originally intended for use as an environmental monitor, but it is so capable and so powerful that it is to be found almost as often in Health and Safety applications. The specification calls for the model 30 to measure from almost the lower limit of the microphone right up to the maximum sensible measuring levels of about 140 dB IN A SINGLE RANGE. This huge range was designed in to make sure that the model 30 could be used in any measuring situation whether or not the initial noise level was known.
The first screen of the model 30 – after the ‘welcome’ screen allows any or all parameters of the measurement to be configured for the task in hand. At one extreme, the model 30 can store Short Leq in the same way as the model 60, or at the other produce similar ‘event’ data although the organisation of the two instruments is slightly different.
One important use of the model 30 – and the model 60 – is the ability to operate with an external battery and microphone in an “outdoor kit”. The model 30 is ideal for this as with the Pulsar “Outdoor Kit” it can measure any sound level that the microphone is capable of registering and thus it can be used in any rural or urban situation for noise complaints or simply for noise investigations.
Because the octaves are measured in real time, as opposed to the parallel operation of the 70 series, they are not restricted to slowly changing noise levels but can register and analyse any type of noise.
Among the metrics that model 30 computes are the full Ln series; thus for environmental measurements, most of the data needed is ready and pre-formatted. The Ln period can be user set for the particular political region.
Special features and functions
Model 30 and 30-2 both have ‘multi-language’ operation. The user can switch between English, German, Spanish and Catalan for the internal screen display.
Using the RS232, the model 30 can be fully remote controlled and the cable and software to do this is supplied. This feature, in conjunction with the optional 230v power unit allow long term measurements to be made in such applications as product noise control or factory noise monitoring.
Application Details and FAQ’s
What is Ln?
Here is not one single Ln, there are an almost infinite number going from say L0,1 to L99,9, but three are in very common use; L10, L50 and L90. The model 60 can resolve up to 7 Ln values from L0,1 to L99,9 to 0,1dB at the same time.
Ln is defined as the level – in decibels – exceeded for n% of the time. Thus L10 is the level EXCEEDED for 10% of the time and L90 is the level exceeded for 90% of the time. Some users call L10 “the annoyance level” and L90 the “background level”. Some users object to using L90 as the background level and prefer L95 or even L99. The fact that the Ln is defined as the level EXCEEDED for n% of the time gives rise to its other name the “Exceedence level” – mostly in the USA. They are also known as the “Statistical levels” by those with a mathematical bent.
Because they are truly a statistical method of describing noise, the Ln values cannot be computed until the end of the measuring period and so there is little point in displaying the running levels during the measurement.
The difference between L10 and L90 gives a good idea of the spread of the noise. If for example L10 and L90 are the same, only one level is being recorded – usually the calibrator. If however, L10 is say 30dB above L90, it suggests that for at least 10% of the time a high noise is coming out of a low background. An example would be many vehicles in a rural situation.
Most environmental measurements specify the use of Ln’s as well as Leq and it is for this type of environmental work outdoors that an outdoor kit is needed.
Outdoor kits for environmental measurements
The Pulsar outdoor kits are VERY competitive and very capable. There are two different outdoor kits differing mainly in the microphone. The two models both have the same waterproof case that has a large internal battery giving about 5 days (150hr) operation. The kits essentially vary only in their microphone and they both have two waterproof connectors to connect to a microphone and an optional computer. Included in the kit are software, cables and space for all the accessories.
There are kits for both data logging units 30 and 60, WK1, a simple unit and WK2 a longer term device that uses a full outdoor microphone. WK2 is similar to the long-term airport monitor microphone and models have been outside for up to 5 years without problems. It comes complete with its own built-in tripod and for transport fits into a shipping tube. See the section on outdoor kits for more data.