In a number of countries manufacturers of kWh meters now have to offer a long-term warranty on their products. The Fritz Kübler GmbH Company of Villingen-Schwenningen in Germany, a market leader in the manufacture of counters for energy metering, now offers a 5-year warranty on all its devices that are built into kWh meters.
When it comes to supposedly cheaper, sometimes illegal copies of European products made in the Far East, then any warranty offered is dubious. Such products, often of unknown origin, come from different sources, so it is no surprise that batch quality and reliability can be irregular. Service, advice and technical support fall by the wayside. If this happens with critical components, such as the counter itself, expected cost savings can quickly turn into large oncosts. In addition there are many patents in the field of counting mechanisms that a manufacturer of kWh meters could unwittingly infringe if he uses counterfeit copies.
The 5-year warranty programme satisfies customers’ needs for reliability with lower costs. It is also an important marketing tool when selling electricity meters, according to a number of kWh meter manufacturers who have just made use of the Kübler programme for the first time. One manufacturer commented: “The Kübler programme helps us because we do not have to try to win a contract solely on the basis of a cheaper price. It would be nice if we had a 5-year warranty on other quality components.”
Kübler has over 40 years’ experience in counter production. Many patents ensure high technical reliability and quality. In the design phase Kübler works closely with the customer to fine-tune the product. A wide variety of both standard and customised versions offer low-cost solutions for incorporation into kWh meters. The product range includes micro counters (K series) as well as stepper-motor driven cyclometer displays (KWH 17) and LCD counting modules.
The patented K-series of electromechanical micro pulse counters are the only products on the market that are both shock resistant and 100% unaffected by magnetic fields. This has been tested by the PTB (German National Metrology Institute) making it easier for a manufacturer of kWh electricity meters to get PTB approval. The devices are compact, with a front cut-out of only 24 x 14mm, and are available in many versions – for PCB or panel mount, reading from above, below or from the side. Special prints, for example with “kWh” or wheels in different colours, are possible. The devices are ideal for installation in submeters or for use in compact kWh meters.
Kübler’s range of counting mechanisms
The larger stepper-motor driven cyclometer displays (KWH 17) are built to a compact space-saving design. This means that in double tariff meters two counting mechanisms can easily be placed close to each other. Thanks to the patented special motor position devised by Kübler, they can be directly soldered onto the PCB without any additional assembly being required. No screws, plug connectors or cables are needed – just solder them in and the job is done. The devices are affixed by means of snap-on or screw mechanisms. The temperature range extends from -40°C to +90°C. A special shielding material ensures that the counting mechanisms remain unaffected by external interference factors, which avoids the need for multiple shielding.
ELECTRONIC COUNTERS ALSO AVAILABLE
The KWH 17 counting mechanisms are primarily for use in 1 and 3 phase electricity meters. The 7-digit cyclometer counter mechanisms with pulse triggering display the values in 5 x 3 mm figures – the same size as in traditional Ferraris meters. Triggering can be initiated either by square-wave or needle pulses. Each incoming pulse advances the decimal position of the counting mechanism by 1/100 of a revolution. The counters can be directly controlled by energy metering ICs, and are superior to traditional counters thanks to their low 25 mW power consumption.
As an alternative to the electromechanical versions, the Kübler range offers LCD PCB mount versions which benefit from EEPROM data backup and have been tested and approved for kWh applications. These electronic counters are also ready-to-install and offer ‘plug and play’ simplicity. Thanks to their small size, these modules offer universal usage in the most diverse applications.