can some one clearly explain why -48 volt DC use in telecom site????
There are two nos of 33Kv/11Kv 5MVA transformers conecting through HT cable from substation having metering at substation itself.One transformer used at a time another remains stand by.Further 11 nos of 11Kv/440V transformers are attached on it and each transformer is having its own Power factor correction panel.Now one 33/11Kv transformer at no load condition/Stand by condition is having power factor in leading side upto 0.21 and while when another tranformer at same situation have power factor in lagging 0.42. Now one thing is clear that transformer one is having 1.5 Km long 33kv cable due to that PF goes in leading side and another is having only 250 mtr length remains him lagging. Now i want to know that how i can maintain the Power factor at no load/ stand by position though both are behaving in seperate manner.
is there any device that works properly accept relay, it may be fuse but if i want fuse of 33kv 300 amp it is avaliable, pls give me details
Is there any abbrevation for STUB in Stub bus protection
why protection and metering CT's are always connected in star why not in delta?
In between UPS out going changer over switch and ups raising main input, both side cable gland producing heat but the cable doesn't get heat,Why?
any body,pls tell me how to done relay coordination ? how to coordinate by TCC curve?how to read the tcc curve?
WHAT IS DEAD END IN PROTECTION?
IN SINGLE PH TRANSFORMER IF LEKAGE IMPEDANCE DROP IS NEGLECTED ,THE FLUX IN THE MAGNETIC CORE and the lekage flux linking a winding are a)proportional to the applied v to the winding i respectively.
who invented active elements? plz give me the complte details of active elements...
In Extended Delta transformer, by which method we can measure the extended angle of transformer?
why the field winding of synchronous machine is excited by dc source
How many current ratings of MCB's are in the market? e.g: 1A, 2A, .......upto.