Why Current Transformers cannot be connected in parallel
Answer Posted / martin vester
As can be seen in the different answers this is not a
simple Yes of No question.
It is possible to use CT's directly parallel, but you need
to determine beforehand exactly what kind of CT's you must
use and for what purpose.
Kneepoint voltages must be equal etc.
For protection purposes this principle has been used in
high impedance (earth)differential protection schemes
including possible overvoltage protection (varistor)
In modern differential protection schemes we always use low
impedance inputs and all seperate CT's are connected to
seperate inputs and never set in parallel connection.
The protection will add seperate CT's for one Side if set
properly automatically.
Therefore I would strongly advise caution to just connect
them in parallel without further calculations and demand of
protection and measuring purposes are met.
See manuals on protection schemes for Siemens on:
www.siprotec.com
| Is This Answer Correct ? | 14 Yes | 0 No |
Post New Answer View All Answers
Draw a 230kv two-bus bar system showing the following. 1.Two generators (150MW) each connected through one 15.75/230KV transformers 2. 1 outgoing lines 3. Two 230/130 KV transformers 4. BUS PT's 5. CT
what is your majour contributions in your present job
What is the permissible limit of shaft voltage for 6.6 KV motors ? Why? Is there any standard is available?
In how we connect watt meter for open & short circuit test of a single phase transformer.
What is pi controller?
how to compare with Relay settings for HT< panels, RMU panel, and PSS CSS transformer?? 1) Load amps, 2)Tripping time, 3) CT ratio, 4)Cable size 5) Transformer KVA rating 6) transformer full load amps
What is shunt voltage and u v voltage witch one best
our factory is going under construction mean time transformer 1000 kva 2 nos &load break swithch 12 kv & 4 nos 750 kva 2 nos & 380 kva 2 nos generator to be errcted.how to arrange earth pits &how to earth connect & neutral pit how to calculate in earth bit size.
Would you recommend to replace all oil filled cables with xlpe cable for hv transmission with the current technolgy for xlpe cable?
If 100 KAV USP dedicated earth got disconnect / Cut. What will happen at load.
i need mat lab program to find out the transmission line losses,regulation and losses
dc supply given to dc generator winding.how is possible? my knowledge is saying the winding will burn. please reply.
How does HT work & Voltage required?
why the frequency and voltage in india is 230v and 50HZ. when compared to USA say 110v and 60 HZ.
How to Calculate The sag of OPGW in Transmission Line???