In 1920 Wilhelm Cremer founded the “Zähler-Eich-und-Reparatur-Anstalt“(Meter-Calibration-and-Repair-Institute) in Königswinter on the Rhine. At that time, calibration was an art that only very few mastered. The meter auditors personally went out and got their first contracts with the utilities in the area. Soon ZERA became known beyond the region for their ingenuity and their penchant for precision.
From service provider for meter calibration, over the years ZERA developed into a highly specialized producer of portable and stationary testing technology for all kinds of electricity meters and instrument transformers. Our solutions have significantly influenced the technological development of testing technology.
In 1950, ZERA developed the first electromechanical error indicator, followed by the electronic testing meter with 0.1% accuracy. At the end of the 90s, ZERA put the first comparator with digital technology and an accuracy of 0.01% on the market. The first primary standard PPCS for metrological institutes was created in 2008. ZERA’s test systems achieved the highest possible accuracy classes that found recognition worldwide.
Starting in 2000, our calibration laboratory received the accreditation from Germany’s National Accreditation Body (today DAkkS) – an approval that metrological laboratories accept worldwide.
Although locally established, ZERA has meanwhile become an internationally operating company: We develop and produce in Germany; however we export over 80 % of our products all over the world.
Precision starts with us. Today we can truly say this. We know that the extraordinary success of the past decades has only been possible thanks to the people that support the company with their knowledge, their ideas and their passion for quality.
Tradition & Quality
As much as the markets have changed over the past 100 years, our corporate values have remained the same: An uncompromising commitment to the highest accuracy and quality, absolute reliability and convincing customer proximity. We know the industry and the needs of our customers from decades of experience. Our engineers and consultants see individual requirements through the eyes of our customers and develop innovative solutions that fit seamlessly into existing processes. Our quality promise Made & Managed in Germany applies not only to our products, but also to our competent advice and qualified service.
We develop and produce in Germany because this is where we find the qualified employees we need – from trainees to engineers. In a climate of appreciation and recognition, many of them have been working in our ranks for decades. 40-year anniversaries are not uncommon. Some families have been with us for generations. In this sense, we are a family business in the truest sense of the word.
We benefit daily from the dedication of our employees and their commitment to our company.
1920 - Hauptstrasse 392
Zähler-Eich- und Reparaturanstalt
Business areas: Maintenance and calibration of meters, repair and sale of repaired meters.
1925 - Rotating watt hour meter
1930 - Rotating watt hour meter
Repairs were handled out by the workshop in Königswinter.
1942 - Rotating watt hour meter
One of the first test facilities at ZERA
View of the historical production facilities
Meter test bench with wooden housing 1955
1959 - Rotating watt hour meter
1969 Ferraris meter
Electromechanical meter and register (mechanical drum-type register)
Meter test bench 1970
1979 Alternating current meter
Electromechanical meter and register (drum-type register)
ILM03 - 1981
DOSSAM - 1990
1991 Hybrid meter
Electronic meter and electromechanical meter (mechanical drum-type register)
1994 CT operated meter
Electro-mechanical meter, electronic data processing
1996 CT operated meter
Meter test bench 2000
WinSAM - 2002
COM3003 - 2003
MT3000 - 2004
Developed in 2002 and received the reddot design award in 2004.
2004 eHZ meter
Electromechanical meter and register, highly simplified tariff structure, remote disconnection
ZERA India - 2005
2005/2006 AMIS meter
PPCS - 2008
2010 EDL meter
EDL21 and EDL40 eHZ or three-point construction
WM3000 - 2010
2013 Basiszähler (electrical energy meter)
COM5003 - 2016
Foundation of ZERYCON GmbH 2017
STM6000 series - 2018
New location - 2019
Relocation to new premises in Königswinter-Oberpleis
s2 series - 2019
Launch of the s2 series – a new generation of portable meter testing.