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Production sequence of Si-spheres and interferometrical determination of the sphere volume

Conformity of Length Measuring Machines

Working Group 5.45

Type and design examination certificates


For the above instruments, the requirements of the Welmec Guide 7.2 and the general conditions of the Certification Body for Measuring Instruments of PTB (ZS-M) must be taken into account in addition.

Test and approval for verification of round timber measuring systems

The round timber measuring systems are used to automatically measure the length and diameter of logs and to calculate the wood volume from these measurements. Calculation is performed in accordance with these volumes based on length measurements and with some quality criteria. The measuring systems thus are subject to mandatory verification. In Germany, only soft wood is marketed in this way. The required approval tests are exclusively performed in situ.


  • Instruction sheet for round timber measuring systems (pdf); currently revised