KoCoS Blog

When distributing electrical energy, it must be remembered that poor current connections cause losses that must be compensated for by additional power from the power generator.

The power loss at the contact point depends on the current and the resistance: P = I²·R

When transmitting high currents, the aim must therefore be to achieve the lowest possible contact resistance at the connection points. The contact resistance is influenced by several variables and increases in the course of the operating time due to aging. By testing at the installation site, a faulty connection can be detected and eliminated.

The quantity for assessing an electrical connection is the resistance. The resistance of an electrical connection is in the micro ohm range. These small resistance values require special measurement technology, such as resistance measurement in four-wire technique (Kelvin method).

In order to assess the quality of a connection, the PROMET SE and PROMET R300/R600 resistance measuring instrument is able to determine the quality of a connection. Due to two voltage measurement inputs, a simple and quick determination of the quality, e.g. of screw connections on bus bars, is possible. The determination is made via the quality factor. This is defined by the ratio of the resistance of the connection over the overlap length to the resistance of the bus bar of the same length.

The quality factor K is the ratio of the resistance RCON of the connection over the overlap length lCON to the resistance RREF of the bus bar of the same length lREF.

     K = RCON/RREF

     RCON: Resistance of the connection
     RREF: Resistance of the bus bar

Therefore, when making an electrical connection, care must be taken to limit aging and provide a low-maintenance and reliable connection.

By determining the resistance or quality of a connection, the correct connection can be verified during installation and maintenance and a reduction in electrical losses, an extension of service life and an increase in plant safety can be achieved.

Do you have questions or additions to the resistance measurement or to our measuring devices? Then contact us via the comment function here on the blog or by mail to info(at)kocos.com.

Spanish user interface at INDEC VD 100 vacuum inspection device

The vacuum inspection systems from KoCoS, which have been tried and tested in practice all over the world, monitor a wide variety of containers such as bottles, jars and cans for leaks in-line during the production process. Containers with insufficient vacuum are reliably detected and removed fully automatically. Highest reliability and easiest handling characterize the processor controlled inspection systems and are the first choice for many food manufacturers.

INDEC VD 100 vacuum testing systems are also increasingly used in Spain for cap inspection. In response to numerous requests by customers at this region, KoCoS decided to develop a Spanish user interface for INDEC VD 100 system and to integrate it as standard in the new firmware. This new Spanish user interface is now available for all new orders for INDEC VD 80 / VD 100 series since spring 2022. Of course, this software update can also be retrofitted in already delivered INDEC VD 100 units.

Users of the INDEC VD 100 can now simply choose their preferred language version between the four user interfaces in German, English, French and Spanish. This significantly simplifies the operation of this INDEC series. Even untrained personnel are now able to generate the relevant sensor parameters (recipes) on the INDEC VD 100. This measure also improves the safety of operation and the acceptance of the INDEC VD 100 series.

The complete commissioning and installation of INDEC VD 100 on the customer's own initiative without the support of a KoCoS technician on site in the Spanish-speaking region is facilitated. This innovation enables the end customer to save considerable installation costs.

KoCoS offers project planning and cabinet production for complete SHERLOG solutions

KoCoS is well known as a reliable manufacturer of high-quality test and measurement systems. However, only a few people know that KoCoS also designs and builds complete control cabinets according customer specifications and supplies them worldwide.

The installation concept of measurement data acquisition for network status and fault detection of electrical power supply networks and systems can be roughly divided into centralized and decentralized installations. Which concept is used is essentially decided by the individual conditions on site. It is therefore not surprising that a mix of both methods is often used.

 

Decentralized solution

In the case of the decentralized solution, compact measuring devices with a few analog and digital inputs are usually integrated into existing switchgear or protective cabinets and are used to monitor one or two bays. One advantage of this method is, for example, the low installation effort due to short cable runs, which also allow the measuring systems to be integrated directly into existing protection or measuring transformer circuits.

 

Centralized solution

In the case of the central acquisition solution, on the other hand, extensive measuring systems are required that have to record larger plant areas, entire voltage levels or even the entire plant. Several hundred measurement inputs are sometimes required for this application. Such measuring systems are then installed in dedicated cabinets in which all the necessary measuring points are brought together.

For such central systems, KoCoS supplies not only the measuring equipment but also, complete solutions in fully wired and tested cabinets.

To this end, KoCoS works out the target concept together with the customer and takes on all tasks from engineering to detailed planning, drawing production, cabinet manufacture, system parameterization and documentation.

Only high-quality components from well-known manufacturers are used in the construction of the cabinets and installed on site at KoCoS.

After commissioning and individual configuration, on-site or remote maintenance and service are also part of the range of services.

 

 

 

 

 

 

 

Any questions or additions on this subject? Then please use the comment function here on the blog or send an e-mail to mjesinghausen(at)kocos.com.

Modeling and generating power quality disturbances

Monitoring power quality (PQ) in the distribution system is an important task for energy suppliers and their customers. In a distribution system, various types of faults cause power quality disturbances. Power supply operation can be improved and maintained by systematically analyzing power quality disturbances.
The power supply is designed to operate with a sinusoidal voltage at a constant frequency. Power quality disturbances occur when the magnitude of the voltage, frequency, and/or waveform deviation change significantly due to various types of faults such as nonlinear loads, switching of loads, weather conditions, etc.
The effects of poor power quality depend on the duration, magnitude, and sensitivity of the connected equipment. Poor power quality can lead to process interruptions, loss of data, malfunction of computer-controlled equipment and overheating of electrical equipment.
It is important to detect and classify power quality disturbances. A variety of waveforms can be generated by simulations and be useful for disturbance detection and classification.
The waveforms of the possible disturbances are created in this description by mathematical models. The EPOS 360 three-phase signal generator and EPOS operating software are available for modeling and generating signals to analyze the events in the power system.

The mathematical models of the power quality signals can be implemented in the EPOS operating software by means of the "Signal Editor" module and generated with the EPOS 360 signal generator. The use of equations offers advantages as it is possible to vary signal parameters in a wide range and in a controlled way.
The following pictures show the different power quality signals which have been defined via the Signal Generator module.

Ideal voltage/current source
An ideal AC voltage source generates a continuous, smooth sinusoidal voltage.

Voltage fluctuations
A drop (undervoltage, voltage dips) or rise (overvoltage, swell) of the mains voltage of at least ½ cycle up to several seconds.

Voltage interruptions
A significant or complete voltage interruption. The interruption can be short-term but also permanent.
 

Harmonics
Distortion of voltage and current waveforms caused, for example, by operation of nonlinear loads.

Transients
A sudden disturbance in the line voltage that typically lasts less than one period and consequently the waveform becomes discontinuous.

In this description, the basis for generating typical power quality disturbances was presented. This signal generation solution includes the EPOS 360 signal generator supported by a PC with the EPOS operating software. The software includes the Signal Editor module, through which parameters such as amplitude, phase angle and frequency can be adjusted for signal generation. Furthermore, the Signal Editor module provides many other functions for adjusting the basic parameters, such as offsets, overlays and harmonics.
The hardware and software functionality makes it very easy to perform the generation of diverse waveforms. The generation of the previously defined waveforms is provided by four voltage and three current output channels of the EPOS 360. The signal generator can thus be used in procedures for testing instruments and devices for power quality measurement and analysis.

For more information, please refer to the following application notes:

  1. Signal generator EPOS 360 - A laboratory for power quality
  2. Three-phase signal generator for precise power network simulations

Do you have any questions about our measuring devices?
Then contact us via the comment function here on the blog or by mail to info(at)kocos.com.

Electrical switching contact for signalling the operational readiness of INDEC VD 100 vacuum inspection device

With our INDEC series vacuum inspection systems, food manufacturers have the certainty that the HACCP principles (Hazard Analysis & Critical Control Points) are fulfilled.

In the past, we have been asked several times by our customers whether INDEC VD 100 inspection system can provide a signal to the higher-level machine control which signals that the measuring system is ready for operation. This electrical switching contact for signalling the switch-on state of INDEC VD 100 system is now also available as a retrofit option for already supplied INDEC systems.

After pressing the main switch on the front panel, the INDEC VD 100 vacuum device is switched on. A visual check of the device by the user ensures that the vacuum tester is ready for operation, the relevant recipe has been loaded and all distances for the sensor head and the light barrier have been set correctly. The readiness for operation of the INDEC VD 100 is signalled to the higher-level machine control system by an electrical switching contact.

An additional optical coupler, which is mounted on the terminal strip as shown below, is used to exclude any interference between the machine controls.

Once the connection has been made according to the updated connection diagram, this ready signal is then permanently available in the customer's higher-level machine control. The filling line is only started after an internal, positive acknowledgement in the control system. This link ensures that all bottles and jars produced are subjected to a closure check.

Voltage transformer VT2 – Extension for ARTES test systems

Testing of protection devices with rated voltages up to 690 VLL

With the steady increase in decentralized power generation, the requirements for power distribution are also becoming more complex. Due to the increasing plant power, these are often connected directly to the medium-voltage distribution grid, but the individual generation units of a plant are interconnected at the low-voltage level. This is raised to medium-voltage at the grid connection point by means of a transformer.

The low-voltage used within a generation plant results in a high current load on the cables for long distances between the individual generation units. In order to minimize the associated power losses, the nominal voltage on the low-voltage side is increasingly being raised to up to 690 VLL, in deviation from the widely used 400 VLL.

With an appropriate configuration, many protection systems can also measure this increased voltage directly without additional voltage transformers. This automatically results in new requirement for the test systems. These are largely designed for testing voltage protection functions up to a nominal voltage of 400 VLL. In order that these systems can also be used for testing with higher voltages, an extension is offered with the VT2 to also meet the new requirements.

During the development of the VT2, care was taken to incorporate the advantages of the ARTES RC3 relay test system. Therefore, the VT2 was also fully integrated into a hard shell case and is thus also ideally suited for use under harsh conditions.

Do you have any questions about the voltage transformer VT2? Then contact us by mail to info(at)kocos.com

Electric mobility is a core component of climate-friendly mobility and innovation worldwide. Electric vehicles generate significantly less CO2, especially when combined with renewably generated electricity.
The research, development and production of batteries and battery cells is becoming increasingly important in this context. In addition to performance, the sustainability of batteries plays an important role. But even more decisive is an efficient overall concept consisting of e-motor, battery and the battery management.
LOTOS 3D measurement systems can support the production of various components from this overall concept effectively and sustainably by 100% control.
For this purpose, the geometry of the components is checked and evaluated for specified tolerances in second cycles. The loading can be implemented manually or fully automated by means of different automation components.

The series fault switch contact at INDEC VD 100 vacuum inspection system to stop the entire filling line

With our INDEC range of vacuum testing systems, food manufacturers can be sure that HACCP (Hazard Analysis & Critical Control Points) principles are being met. KoCoS vacuum inspection systems are characterised by their superior detection sensitivity and automatic separation of defective products.

Sometimes the lid feed in the capping machine is interrupted. As a result, all containers leave the capping machine without lids. This is particularly annoying because often all uncapped jars have to be disposed of with costs.

Increasingly, our customers who use an INDEC 100 vacuum testing system for cap inspection in production want to stop the filling process immediately if this error, also known as a serial error, occurs. This serial fault switch contact is now also available as a retrofit option for already delivered INDEC VD 100 vacuum testers that have already been delivered.

Once the connection has been made in accordance with wiring diagram, that stop signal is then permanently available in the customer's higher-level machine control system.

This retrofitting of the series fault switch contact on the INDEC VD 100 enables the customer to intervene immediately in the filling process and minimize the scrap of defective containers.

Yesterday - Today - Tomorrow

Background
Germany wants to do more for the climate. Following the ruling of the Federal Constitutional Court in March 2021, the German government announced that CO2 emissions are to be reduced by 65% by 2030 compared to 1990 levels and not - as previously planned - by 55%. This basically requires more electrical energy from renewable sources than previously planned.
Depending on how high the demand for electrical energy is estimated to be in 2030, there will be completely different orders of magnitude in which wind and solar power plants will have to be expanded in order to achieve this 65% target.

How will the future energy demand in Germany develop?
So far, the Federal Ministry of Economics and Technology (BMWi) has assumed that electricity consumption will not change significantly over the next nine years until 2030 and will remain at around 580 billion kWh. Looking at the past, this does not seem wrong. "In the last ten, 20 years, electricity consumption has been relatively constant," Johannes Wagner of the Energy Economics Institute at the University of Cologne (EWI) told Deutsche Welle. "We had a gross electricity consumption of about 600 billion kWh over a long period of time. That only went down relatively sharply in 2020 due to special effects from Corona."
But that need not hold true for the future. Various experts believe that the federal government's planning to date is too cautious. Even SPD chancellor candidate Olaf Scholz recently indirectly criticised his ministerial colleague Peter Altmaier (CDU): "Anyone who claims that electricity consumption will remain the same until 2030 is lying to himself and the country."
So what if electricity consumption does not stay the same at all, but perhaps even rises sharply? That is in fact the scenario that various energy experts are assuming. "The expert commission for monitoring the energy transition, of which I am a member, has estimated a value for electricity consumption that is significantly higher than that of the German government," says Veronika Grimm, a member of the government's Council of Experts (the “Wirtschaftsweisen"). "We are moving around a value of 650 billion kWh and are thus still at the lower end of the spectrum," Grimm said in an interview with Deutsche Welle in July 2021.

Energy demand in the first half of 2021
According to Zeit Online, more energy was needed and more CO2 was emitted in the first half of 2021 than in the same period of the previous year with approx. 600 billion kWh. The share of fossil fuels increased compared to the previous year.
A rather cool winter (2020/2021) and the restart of the economy after the Corona slowdown caused energy demand in Germany to rise in the first half of 2021. According to calculations by the Working Group on Energy Balances (AGEB), consumption increased by 4.3% compared to the same period last year, to approx. 625 billion kWh.

Because more electricity was produced with brown and hard coal than in the same period last year, carbon dioxide emissions increased by 6.2%. The consumption of lignite rose by about one third in the first six months of this current year, that of anthracite by almost 23%. The increase in fossil fuels in electricity generation is mainly due to the fact that less wind power was generated.

Estimates of Germany's future electrical energy demand
On 13 July 2021, Federal Minister of Economics and Technology Peter Altmaier presented a first new estimate of Germany's electrical energy demand in 2030.
In the BMWi press release of 13 July 2021, Federal Minister of Economics Peter Altmaier states here, among other things: "The new version of the Climate Protection Act and our new ambitious climate targets, which the Bundestag and Bundesrat passed at the end of June 2021, require an adjustment of our analyses of electricity consumption in 2030."
Today it is already clear that Germany's future energy supply will essentially be based on two energy sources. On the one hand, on electricity from renewable energies and, on the other, on hydrogen produced with the help of renewable energies.
An initial estimate of electricity consumption in 2030, prepared by Prognos AG on behalf of the Federal Ministry of Economics, comes to an electricity consumption of between 645 and 665 billion kWh. The following assumptions were made: 14 million electric cars, 6 million heat pumps and 30 billion kWh of electricity for green hydrogen.
According to the German Wave, the think tank Agora Energiewende also estimates the electrical energy demand in 2030 at 650 billion kWh. The EWI calculates that 685 billion kWh will be needed in nine years. The German Renewable Energy Federation (BEE) assumes 745 billion kWh in 2030 and the Fraunhofer Institute for Solar Energy Systems (ISE) even expects an energy demand of 780 billion kWh in 2030, i.e. 70 to 200 billion kWh more than the Ministry of Economics currently forecasts.

Higher energy demand due to e-cars, heat pumps and electrolysers.
The demand for energy is growing due to the shift to e-mobility and the changing heating of buildings (e.g. with electrically powered heat pumps). It is also becoming apparent that industry will have to switch to synthetic energy sources, such as hydrogen. For the production of green hydrogen through electrolysis, there is in turn an increased demand for electrical energy.
"The German government's goal of creating electrolysis capacities of five gigawatts by 2030 alone will require a considerable amount of additional electricity. To achieve this, we need to estimate an additional 20 billion kWh of electricity," says Veronika Grimm. This energy demand corresponds to more than one sixth of the total energy provided by wind power in 2020.
So more electricity will be consumed. On the other hand, there are of course efficiency gains that reduce electricity consumption. In this area, the German government has set itself the goal of reducing electricity consumption by 25% by 2050 compared to 2008 through greater energy efficiency. However, these efficiency gains cannot compensate for the increased demand for electrical energy.


In addition, Agora Energiewende criticises that economically highly profitable efficiency potentials have not yet been systematically exploited, even though market-ready technologies are already available today.

How large must the growth of renewable energies be?
Based on the electricity estimates of Agora Energiewende, Germany would have to expand about ten gigawatts of photovoltaics, 1.7 gigawatts of onshore wind and four to five gigawatts of offshore wind annually by 2030. In recent years, these outputs were only achieved in the record expansion years.
It will probably not work without its European neighbours. "Currently, Germany exports electricity abroad," says Johannes Wagner (EWI), "in the medium term, we must expect Germany to become a net importer for the time being."
It will be quite challenging and many mechanisms will have to be set in motion to push the expansion of renewable energies, says expert Veronika Grimm.

Sources:
Deutsche Welle, ZEIT ONLINE, dpa, BDEW, Statista, BMWi, AGEB, ZSW, ISE, Agora Energiewende, EWI

When testing electrical components, such as motors, accurate, reliable and powerful power supplies are required. Furthermore, in production, many processes are automated where time is an important factor in testing.

The voltage sources of the EPOS CV series are designed for above mentioned requirements, where adjustable output voltages up to 270 VAC / 300 VDC are needed.

A special feature of the EPOS CV voltage sources is the variable transformer with a fast motor drive that controls the AC/DC output voltage. A variable transformer is used because it enables a continuously adjustable voltage and is insensitive to current peaks. With the EPOS CV voltage sources, the output voltage can thus be steplessly adjusted to the respective requirements automatically and manually. 
The voltage sources are provided with internal voltage and current measurements via a controller, which significantly increases the efficiency of the system. The internal measurement electronics permanently control and regulate the values and ensure function monitoring. Among other things, the voltage sources are overload-protected with a circuit breaker that disconnects the output circuits in the event of a short circuit, for example. 
The series has been equipped with a convenient operating unit with touchscreen, jog wheel and function keys. The system is easy to operate and extremely user-friendly due to the control unit and display.
The output voltage can be set in stand-alone mode via the rotary knob. In automatic mode, the EPOS CV voltage sources can be easily integrated into own applications via an Ethernet interface.
The voltage sources of the EPOS CV series are available in different power classes. They are used wherever continuously adjustable DC and AC voltages in the range up to 270 VAC or 300 VDC are used. All models are suitable for connection in the frequency range 50 Hz / 60 Hz. 

Typical data of the motor-driven EPOS CV voltage sources are:

EPOS CV 821

  1. one phase
  2. 1 x 15..270 VAC
  3. 1 x 15..300 VDC
  4. 1 x 30 AAC
  5. 1 x 20 ADC
  6. 8,1 kVA

EPOS CV 831

  1. one phase
  2. 1 x 15..270 VAC
  3. 1 x 15..300 VDC
  4. 1 x 40 AAC
  5. 1 x 30 AAC
  6. 11,5 kVA

EPOS CV 753

  1. three phase
  2. 3 x 15..300 VACPN
  3. 3 x 15..520 VACPP
  4. 1 x 15..300 VDC
  5. 3 x 25 AAC
  6. 1 x 32 ADC
  7. 22,5 kVA

EPOS CV voltage sources provide both a high output voltage and a high output current. Especially when operating motors, large starting currents occur when the full rated voltage is applied, which can be many times the rated currents. The voltage sources are capable of supplying these current peaks up to 10 times the rated current of the load during the switch-on process.

Testing is the only way to ensure that electrical components function correctly. By analyzing the curve signatures of the actuating and operating currents and the resulting characteristics, it is possible to make accurate statements about the behavior of components and thus draw conclusions about their electrical and mechanical condition. For such analyses, KoCoS provides powerful AC/DC sources in the form of the EPOS CV series of voltage sources.

Would you like to find out more? You can find more information at the following link or contact us by mail at info(at)kocos.com.