Latest Posts

The ECA has announced the creation of Power Players - a new initiative which aims to identify and promote some of the leading professionals across the building services engineering sector, by providing a platform to showcase innovation, excellence and success.

Power Players is being run across the country by the ECA and partners, who will be confirmed in due course. The initiative will open to entries in Spring 2017.

Bsria is proud to support Data Centre World taking place at ExCel London on Wednesday 15th and Thursday 16th March 2017. As part of supporting Data Centre World, Bsria will present at the conference and be on hand to answer your data centre design and build questions at the exhibition.

A review of key issues affecting the future of electrical contracting has been published by the Electrical Contractors’ Association (ECA), NICEIC and Elecsa.

Harting has reaffirmed the recent UK launch of its Han-Modular Switch US4 connector as a strategic part of its Industry 4.0 portfolio. This connector is designed to save control cabinet space, reduce wiring and improve distributed networking, specifically in support of Industry 4.0 modernisation programmes.

Luceco, the manufacturer and distributor of high quality and innovative LED lighting products and wiring accessories, announces its successful initial public offering, having started trading on the London Stock Exchange's main market on 20 October 2016.

Allegro MicroSystems Europe has announced a new package option for its A119x/A119x-F (A1190, A1192, and A1193) family of two-wire, unipolar, Hall-effect switches, which can be trimmed by the user at end-of-line to optimise magnetic switch-point accuracy in the application.

The introduction of digital PD measuring systems, has resulted in improved PD measurements, far exceeding the capabilities of older PD measuring systems.  The MPD600 applies multi-channel, synchronous processing of PD signals that make efficient statistical analysis, not only for discrimination between PD and interference, but also for fault-type identification and location.

The MPD600 system is designed to perform continuous and synchronous multi-channel PD measurements in real-time.

This system is modular in design, consisting of one or more acquisition units, which can be placed in close proximity to the asset(s) being monitored, and connected to a PC via a fibre optic connection, allowing for greater distances between the PC and the acquisition unit(s). The PD signals are filtered, amplified, and digitised in real-time.  The centre frequency can be freely chosen in the range from dc up to 20 MHz, while the bandwidth is selectable from 9kHz up to 3MHz.  This allows the operator to "tune out" disturbances and to reach an optimal Signal to Noise Ratio, even under noisy on site conditions.  For ac phase synchronisation, as well as for ac waveform display and amplitude reading, a second A/D-converter digitises the voltage curve.  All data acquisition and pre-processing are performed in the acquisition unit, close to where the signal was measured, to guarantee optimal performance in speed and signal quality. A four parameter vector for each single PD pulse is identified: [n; qi; ji; ti], where n is the acquisition unit number, qi the apparent charge value, ji the ac voltage phase angle and ti the absolute time. In parallel, the instantaneous value of the ac voltage is sampled. All parameters can be stored for off-line processing, replayed or exported to an application such as MatLab for post-processing.  An oscilloscope mode and a FFT (Fast Fourier Transforms)-based spectrum viewer are provided to analyze input signals with full bandwidth, and the ability to locate PD by TDR (time-domain-reflectometry) are also included. Each acquisition unit contains an internal test generator to enable closed-loop self-testing.

3-PHASE AMPLITUDE RELATION DIAGRAM (3PARD)

The 3PARD was originally designed for evaluation of three-phase PD measurements. 3PARD application requires three independent PD monitoring channels such as the capacitive taps of three-phase transformer bushings, or coupling capacitors connected to the terminals of a generator. In the case of measurements on long three-phase single-line cable systems, cross-bonding links enable distributed inductive three-phase PD detection for online measurements.  3PARD visualizes the relationships between the amplitudes of a single PD pulse in one phase and its cross-talk generated signals in the other two phases. 

By repetition of this procedure for a large number of PD pulses, PD sources within the test object, as well as external noise appear, as a clearly distinguishable concentration of dots (a cluster) in a 3PARD.

3-CHANNEL FREQUENCY RELATION DIAGRAM (3CFRD)

The 3-channel frequency relation diagram correlates synchronous multi-spectral measurement to separate PD from interference. In contrast to 3PARD methods, 3CFRD evaluation does not necessarily require three independent acquisition units and thus, can be used with a single MPD600 acquisition unit.

Multi-spectral PD measurements are based on pulse spectra correlation by applying three different band-pass filters  simultaneously. The three band-pass filters can be tuned to areas with low interference level. In general, the first band-pass filter should be tuned to a low centre frequency (fc1) to enable conformity to IEC or IEEE standards. The second (fc2) and third (fc3) band-pass filters are tuned to higher centre frequencies, where pulse propagation effects caused differences in the spectral responses of  the PD signal. By proper choice of the band pass center frequencies, it becomes possible to perform PD measurements according to the standards while, at the same time, removing practically all superimposed interference.  3CFRD correlates the output of the three band-pass filters in a similar fashion to the 3PARD.

CONCLUSION

By using the OMICRON MPD600 with synchronous multi-channel measurements in real-time it is now possible to measure partial discharges in the field and discriminate it out from other sources of noise within that environment.  Secondly, by using evaluation methods such as 3PARD, and 3CFRD, further analysis and location of partial discharges are now possible.

Omicron

www.omicronenergy.com

As network operators and consumers become more and more aware of the importance of the security of supply in electrical power systems, they are becoming increasingly interested in the continuous measurement of power quality. In order to identify problems at an early stage and to be able to take appropriate preventative measures, the first step is to use a suitable measuring system to closely analyse the supply system or technical equipment over a longer time period. Depending on the specific facility and application, the requirements to be met by a suitable measuring system are very varied and include a wide range of different measurement functions.

Formerly Borri, Power Control (PCL) has received a glowing review for its electrical expertise and high performance UPS solutions from one of the world’s largest travel sites.

Due to continued business expansion, the global travel review company recently replaced its 60kVA, end of life unit with the purchase of two Borri B8000FXS 20kVA UPS units, which are now handling added capacity the company’s newest facility.

  • 08 February 2017 - 08 February 2017
  • 8 February 2017
  • Barbican Exhibition Hall 2 London

  • 15 March 2017 - 16 March 2017
  • ExCeL London

The 24th International Conference & Exhibition on Electricity Distribution
The Scottish Exhibition and Conference Centre (SECC), Glasgow, UK

  • 12 June 2017 - 15 June 2017
  • 12 - 15 June 2017
  • Glasgow

Data Centre news from our sister title

@elecreviewmag