More information?

Michel Brakel
Department Sales & Planning
Time may well be the most evident example of the importance of accurate and traceable measurement. Everyone has at one time missed a train and then it comes down to the second. In a skating championship the difference between winning and losing may be only one hundredth of a second. For position determinations via GPS, even more accurate time recording is needed.
Time and frequency are quantities that are applied in all kinds of industrial processes, data protection systems, telecommunication, astronomy, geodesics, navigation and medical research. In stock trading, the time stamp on the transaction is of immediate influence on the price the buyer or seller pays or receives.
VSL supplies various services involving very accurate and traceable measurements in the field of time and frequency to clients including manufacturers and suppliers of frequency- and time-measuring instruments, research institutions, defence, telecom and internet providers and banks. Also, VSL works in a European context on different research projects, including a study into the possibility to employ the existing glass fibre network for distributing extremely precise and stable signals.
Michel Brakel
Department Sales & Planning
Online request for recalibration quotation
VSL supplies the most accurate calibrations in the field of time that are directly traceable to the national time standard. VSL’s scope runs from frequency measurements with a relative uncertainty of 0.000 000 000 000 2 Hz/Hz to stopwatch calibrations with an uncertainty of 0.014 seconds per day. VSL’s calibration reports are internationally renowned and ensure worldwide acceptance for your products.
Calibration of measurement instruments
For accurate, traceable time or frequency measurements, the measurement instruments used must be calibrated regularly. VSL calibrates devices including stopwatches, counters, clocks and oscilloscopes.
Time service bulletin and time synchronisation
Via the ‘Time Service Bulletin’, VSL offers a weekly report of information about signals whose time or phase difference has been measured with respect to the national time standard for UTC (VSL). Information from IERS and BIPM is also forwarded in the Time Service Bulletin. The Time Service Bulletin is offered by subscription. Time synchronisation for computers via the internet is available for free via ntp.vsl.nl.
Marc Pieksma
VSL’s expertise in the field of time and frequency is in regular demand for specific applications. This happens by commission of very diverse companies and organisations, including the aerospace industry and financial institutions.
With our thorough knowledge of measurements and interpretation of measurement data, VSL can provide you with services including:
Of course, each situation is unique. Would you like to know what we can do for you? Please contact us.
Peter van Otterloo
To ensure optimum quality of their measurements, laboratories frequently hold in-house quality checks. However, over time deviations in the measurement equipment can occur that cannot be detected by these checks. VSL regularly organises (international) interlaboratory comparisons, through which your laboratory’s measurement results are compared anonymously to those from VSL as primary standards laboratory and those from other participating laboratories.
VSL organises such interlaboratory comparisons annually in, among other things, the field of:
Need for a different interlaboratory comparison?
Do you require another type of proficiency testing? Then please let us know. We can assess the demand. Possibly there are other laboratories that would like to participate and then we can organise a loop comparison. It is also possible to organise a bilateral comparison with VSL.
Click here for more information about inter-laboratory comparisons.
Marion de Niet
Course coordinator
Would you like to know more about the accurate measurement of time and frequency? VSL offers training courses which are presented by specialists in their field of work. Theory is always combined with practice.
After completing the course, you receive proof of participation.
Erik Smits
Test facility performance
VSL offers CMC Certification. CMC stands for Calibration and Measurement Capabilities. In this, only the performance of the test facility is considered. You receive a certificate containing the calibration facility’s measurement uncertainty and a manual about traceability. With this certificate, you can demonstrate that the measurement uncertainty has been established by an authoritative and independent national metrology institute (NMI).
Click here for more information.