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KoCoS offers project planning and cabinet production for complete SHERLOG solutions

08. April 2022, mjesinghausen - Digital fault recording

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.

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Generating power quality disturbances

21. March 2022, jdreier - Power source

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.

Test plan with PQ signals in the EPOS operating software

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:

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.

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Signalling operational readiness

07. March 2022, gherrmann - Vacuum inspection

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.

Updated connection diagram - Additions to the connection plan marked in blue here.

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Voltage transformer VT2

14. February 2022, bfleuth - Power source, Protection relay testing

Voltage transformer VT2 – Extension for ARTES test systems

Testing of protection devices with rated voltages up to 690 V_LL

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 V_LL, in deviation from the widely used 400 V_LL.

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 V_LL. 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

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E-mobility – Accompanying process and quality control with LOTOS

11. January 2022, pzube - 3D measurement and inspection

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.