Login 
We are delighted to announce that the Optimus+ sound level meter has achieved PTB pattern approval. This means that our latest firmware and features have been independently verified as meeting the highest standards in noise measurement.
The Class 1 Optimus+ Green (CR:171X Series) selected Class 1 Optimus+ Red (CR:161X series) sound level meters have been type-approved by the PTB to the latest standards for sound level meters, DIN EN 61672, which is the same as IEC 61672.
The Physikalisch-Technische Bundesanstalt (PTB) is the German National Metrology Institute and is recognised as one of the most prestigious national test laboratories in the world.
After a series of long and detailed tests, which include both electrical and acoustic verification, approval numbers have been issued for the Class 1 Optimus+ Green and Optimus+ Red instruments as follows:
CR:161A, CR:161B & CR:161C
CR:1710, CR:171A, CR:171B & CR:171C
The certificate number is DE-22-M-PTB0017
The reference number is PTB-1.63-4091643
The standards that were used in the verification were:
− DIN EN 61672-1:2014-07: Elektroakustik – Schallpegelmesser – Teil 1: Anforderungen
− DIN 45657:2014-07: Schallpegelmesser – Zusatzanforderungen für besondere Messaufgaben
− Welmec 7.2 „Softwareleitfaden“ (2015)
What is Type Approval?
Type Approval, or Pattern Approval, is a method where a test laboratory such as the PTB tests an instrument against a set of standard tests to ensure that it meets the performance claims of the manufacturer.
The Optimus+ sound level meters have been designed to meet the requirements of IEC 61672 (and the corresponding EN and DIN standards) and so these independent tests have been carried out to verify that the instruments do indeed meet these requirements. The IEC 61672 standard is in three parts.
The first of these is known as Electroacoustics – Sound level meters – Part 1: Specifications and this defines the performance specifications for the instruments.
Part 2 is known as Electroacoustics – Sound level meters – Part 2: Pattern evaluation tests and this defines the tests and checks that a laboratory must carry out when they are testing an instrument for Type or Pattern approval. These are the tests that the PTB have been carrying out on the Optimus+ sound level meters.
Part 3 is known as Electroacoustics – Sound level meters – Part 3: Periodic tests and this defines the tests that should be carried out during a Periodic or routine verification.
This post has more information about the different sections of the IEC 61672 standard.
You can view our certificate here.
