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To exclude the voltage drop across the source transformer go to Balanced Studies > Load Flow Setup -- you will see the first option is a checkbox, untick it.

General Form: Iz = In / (Ca * Cg *...) For adjustable protective devices: Iz = Ir / (Ca * Cg *...) Iz is the minimum cable current carrying capacity - see BS7671 Appendices 4.5 as per sheet. It is tabulated current carrying capacity of cable with derating factors. Simultaneous Overload -...

Would agree with all the previous comments particularly . prc: The residual magnetism in a core may remain not weeks ,even months gradually decaying away. So you cannot link magnitude of inrush linearly with the time of keeping in de-energised condition. Why you are seeing differences in...

dpc thanks you for input - my query relates to Europe. Looking at Siemens Simaris software (PD Curves) a current let-through curve is provided (see attached with random values plotted on the curve). This was what my query was referring to. Any thoughts on these? Thanks Link

All, I see many LV protective devices come with current limiting abilities in the form of a curve from which one can determine the limited current based on the initial short circuit current. Those involved studies, from what I can see the protective libraries in commercial software do not have...

Have you considered the different pitch angles to be a possible source? Paralleling dissimilar generators with different pitch angle can give rise to high levels of current flowing on the neutral/harmonic current (imbalance). Have you measured the neutral? Best results are paralleling...

What are the pitch angles of the generators, are they the same?

Hi all, I have been viewing a demo model wind-farm in one of the main power system analysis softwares. Viewing the frequency sweep results I can see 'Z' which has a resonance point as expected at the PCC at a certain frequency (Utility+Wind-farm connected). I am also able to display the...

Check out ArresterWorks.com - it has really good information and guides that may be helpful.

Hi all, Has anyone in their experience had issues with terminations burning out in which you had multiple conductors paralleled per phase, not in trefoil eg. 3 no conductors bunched together for L1 and separated from same configuration for L2 and L3. Cables (L1,L2,L3) would be coming from a...

NFPA 70E - Standard for Electrical Safety in the Workplace Gives details of the requirements for: Selection of PPE Signage Shock Hazard Analysis Flash Hazard Analysis Article 130.3 and associated sub sections give details of the requirements of arc flash hazard analysis. As has been said by...

Hi all, Has anyone had much experience working on large scale solar farms? I am looking to find information on grid compliance requirements (harmonics, voltage stability etc). I am based in Europe and my country has not published any specific grid codes relating to this area yet. I see there...

Thanks for the link davidbeach, its good to see a compilation has been created. Juleselec, thanks for the detailed response - that makes a lot of sense now and is good to know for future reference.

Hi all, I see IEEE have a number of Test Bus Systems available, some of which are available in power system simulation software such as DIgSILENT. I would like to know the significance of these systems and what can they be used for? Are these essentially power systems that have been solved in...

I have been thinking about all the responses of this thread and something that has sparked my interest and has been discussed in the thread is how does one verify the harmonic data they record? I would be interested to hear peoples thoughts on this. (magoo2 - thanks for the suggestion on...

Hi all, Thank you everyone for taking the time to contribute information, I have learned a lot from the information provided and will do further research into what has been suggested by all. @scotttf - You mentioned you work for a manufacturer that specialises in the type of equipment I am...

Just found the document I was reading at the time regards "capacitor wings": Link The second page gives an overview of that particular technology. RD

Scottf thank you for the reply, I was looking at the technical literature for a capacitive voltage divider, and it said said something about capacitor windings. I may have misread the document but it didn't make a lot of sense to me and hence why I asked. Can you recommend any manufacturers? I...

Hi all, I am in the process of doing some final year university project research and felt it would be a good idea to post a message here as someone may have or information or be able to point me in the right direction. I am looking for a method to measure medium voltage harmonics most likely...