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I would also like to take a look at the pictures of this and similar transformers. mm

Can anyone tell me what is the MVA of the world's largest transformer, how many tons with oil and who makes it?

Yes a generator that turns it into a 3 terminal line. Go on. mutimuti

In this example the infeed considered a tap somewhere along the protected line. Why cant this be done?

The book (Horrowitz) says even if an infeed exists, we can ignore it for the purpose of Setting Zone one, but must consider it for Zone 2 & 3. Why? Whats the latest trend?

What is a 3-input Differential Relays dpc?

DPC, STEVENAL, RalphChristie, I salute you all. You are repositories of good information, dont need consultants! With differential protection, co-ordination and setting are not serious issues (but cost is). mm

How is it really done? It seems you have bi-directional relays at the source bussbar and uni-directional relays at all the other busses looking towards the source. You then have two sets of uni-directional relays looking in opposite directions. When setting do you consider the situation as...

I am for HOIKI too! We just got two analysers, usb port and the nice thing are the CTs. They are just like a rope (I think its some kind of optical coupling) can surround the biggest bussbars and the smallest, an LED automatically indicates whether is 500A or 1000A. Excellent instrument, can...

I appreciate your responses. Looks like we need to get to the bottom. Would it be possible to get a manufacturer's declaration of what the absolute maximum ratings are. mm

Can a 150:5 CT survive a 25-30kA fault current?

I am looking for guidelines for protecting distribution systtem networks, especially between 11kV (possibly lower) and 66kV. In particular explicit information on when to use fuses or a combination of fuse and circuit breaker. Thank you.

Thank you apowereng! You were the only person having the remotest interest in this question. I refer to a radial distribution feeder, with several busses from which loads are drawn. One method involves setting relays based on 1/3 of fault current and time dials at each bus based on maximum...

Can anyone tell me the industry standard for protecting radial networks. Some publications for example base the "pick up" on a fraction of minimum fault current, typically 1/3 and the time dial settings based on maximum fault current. Still others use peak load current for pick up and fault...

I have connected everything to just switch one light. I have programmed it. I am using Moeller PS4-141-MM1, PLC. When I try to transfer the program, there is a complaint about an already existing program (the last programme was for a different task). There is also a complaint about the...

Thank you all for all those that participated in this "dull" topic. "Dull" but not trivial. In some ways I was little understood, especially the object of the exercise. We start our studies at a fairly basic theoretical level and then proceed to more complex situations of the world. So your...

No transformers! and almost 100% of the problems that I am dealing with have no transformers so the problems are greatly simplified. mmt

I just thought of a new on Per Unit Power System Analysis thread to finalise a previous discussion hoping also that other academics can benefit from my experience. I have just finished doing the simulation of a system example by Stagg & Ei-Abiad,shown in his "Computer Methods in Power Systems"...

Thanks all of you who are in this debate. The text book examples are all per unit representations of the systems involved and in my opinion when this is done lines cannot be distinguished from transformers. The caution from jghrist is noted. I have not had to convert physical units to per...

Rbulsara, thank you for mentioning the IEEE book, I will try and find it. It looks like a useful book. I know the PU system very well and I also teach it. Z (pu) =Z(ohm)*(Vbase (kv))/(Sbase (MVA)^2). Clearly, if you make Vbase =1kV and Sbase=1MVA, then Z(pu)=Z(Ohm). Actually may be I...