We have a factory that requires 6 MVA electric power , Can we use one large transformer and limit the fault current with NGR? our transformer is 11/0.4 KV
Good question. But i haven't found any thing related metrosil rating yet. If it is each relay maker indicates above which voltage their relay will require metrosil. So suppose you are using relay of a particular manufacturer. Then check their voltage limit for metrosil requirement like 3 kv or 2.5 kv. If the calculated voltage is higher than that, you have to ask for metrosil. And the manufacturer as per their standard design will provide the metrosil. However i will find further if i can get the standard ratings of metrosil....
Can you give me reference? As per as i am concerned the ct terminals are given like that. And that is nomenclature only. Directional of primary and secondary current will be opposite. And under no circumstances the phase ct will give feed to relay as they are residually connected. So for a balanced suppy, (there could be negetive sequence current but no zero sequence or third harmonic current) the three ct will produce a net result of zero. Please watch my ct connec3for detection of earth fault video. You will have a clear idea.
Thank you sir 👍👏 do more videos like this
Wow....amazing explanation
If NGR available is it require the metrosil
Very good. Thanks 🙏🙏🙏🙏
Thanks so much, very useful video
Super sir keep it up 👏👏
What will happen p1 and p2 direction are changed what is theory behind this direction changing
sir can you confirm the position of NCT and NGR in the circuit?
We have a factory that requires 6 MVA electric power , Can we use one large transformer and limit the fault current with NGR?
our transformer is
11/0.4 KV
Great explanation 👌
AWESOME EXPLANATION
sir what are the ratings of metrosil
I. e current rating voltage rating power rating. In market how to order a metrosil
Good question. But i haven't found any thing related metrosil rating yet. If it is each relay maker indicates above which voltage their relay will require metrosil. So suppose you are using relay of a particular manufacturer. Then check their voltage limit for metrosil requirement like 3 kv or 2.5 kv. If the calculated voltage is higher than that, you have to ask for metrosil. And the manufacturer as per their standard design will provide the metrosil.
However i will find further if i can get the standard ratings of metrosil....
Why do we use stabilizing resistor????
sir please make video of motor relay setting calculations video
Plz do a video on relay burden calc - for both VT & PT
Pt and vt are same.. relay burden on ct will come in few days
Why NCT direction is changed i.e p2to p1
During Fault , Current Direction will flow to words Star Point. So Current Entry is P1.
pls more for VC/SF6 control wiring with diagram
What is difference between restricted and unrestricted earth fault please elaborate it?
Please see my restricted earth fault philosophy video. Restricted earth faulr means the protection will work within a certain zone.
REF Relay will Operates , When Fault Occurred inside the Transformer Secondary winding , That is Called in zone. (Before Phase CT )
Sir you have not explain.. How metro seal work.. When heavy voltage occurs
That will require another video..... This video is only for metrosil calculation
Sir 5 mva transformer ki protection scheme kya hoti hai?उस पर भी एक vedio बनायें।10 mva transformer की protection क्या है?
As shown in my video. Only trafo differential relay is mandatory which is not required for trafo less than 5 MVA.
In Phase CT side P1 &P2 and S1 & S2 to be reversed , otherwise Current will not nullify in normal Operation.
Can you give me reference? As per as i am concerned the ct terminals are given like that. And that is nomenclature only. Directional of primary and secondary current will be opposite.
And under no circumstances the phase ct will give feed to relay as they are residually connected. So for a balanced suppy, (there could be negetive sequence current but no zero sequence or third harmonic current) the three ct will produce a net result of zero. Please watch my ct connec3for detection of earth fault video. You will have a clear idea.
If the both the terminals are reversed then it will not effect the result
I did REF testing Practically by Primary Current injection. Both Stable and unstable condition by Reversing CT Secondary terminals.
Could you Please share the circuit diagram at
electricaltechnology04@gmail.com