Two Incoming Feeders connected to secondary of Two Winding Transformer.
Two Incoming Feeders connected to secondary of Two Winding Transformer.
(OP)
Dear All,
I know that this question is a beginner's question, but it never came to me, that's why I turn to you.
I would like to know if it is possible to connect two feeders to a secondary of a transformer. Both provide different current, but at the same voltage. I give you a part of the scheme. I understand that what would be done is to connect these two feeders to a common LV Switchgear , and from there depart with a single line to the transformer. Attached is a descriptive Picture of my question.
Thank you very much, any help is more than welcome.
I know that this question is a beginner's question, but it never came to me, that's why I turn to you.
I would like to know if it is possible to connect two feeders to a secondary of a transformer. Both provide different current, but at the same voltage. I give you a part of the scheme. I understand that what would be done is to connect these two feeders to a common LV Switchgear , and from there depart with a single line to the transformer. Attached is a descriptive Picture of my question.
Thank you very much, any help is more than welcome.






RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
How do you propose to control the KVA sharing ratio?
The KVA sharing may be adjusted by adjusting the voltages.
The sum of the cable KVAs may be greater than the KVA demanded by the load.
The KVA sharing ratio may be quite different than the kW sharing ratio.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
Cheers,
mgtrp
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
-JFPE
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
I was quite young so it was a long time ago that I worked on series lighting circuits.
These were street lighting circuits, not Christmas tree lights.
Open circuit voltage cold hit several thousand Volts.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
@jfpe The Project is a PV Plant. The transformer is 0,480 / 11 kV, and two incomings from two separate Inverters are connected, each one wich different power and current as per the Picture attached.
@mgtrp: Cables are sized equal, but using differnet amount of runs.
Feeder 1: 2x(4x240) mm2 Cu XLPE/SWA/PVC
Feeder 2: 3x(4x240) mm2 Cu XLPE/SWA/PVC
Then, the prmary side of 11kV transformer is connected to MV Swictchgear incoming feeder.
Could you be kind to provide examples of paralell conenction of several feeders in paralell in a single winding of Two winding Transformer?
Thank you very much in advance,
Miguel.
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
- Voltage Level = 480V Feeders
- Phase: Both Feeders shall be equally phased in order not provide lagging or leading voltages
- Frecuency, shall be both for both feeders, is there any tolerance?
Thanks
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
Usual design for the two 480V windings is to have a 480V breaker on each winding connecting to one of the feeders. E
If you parallel the 480V windings, as you imply, your short circuit levels will be much higher. You will also have to do some bus work to connect the eight 480V terminals in parallel (3 phase + neutral) x 2.
Look at the nameplate of the transformer. Does it show two or three windings and 3 or 6 480V phase connections?
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
rcwilson, I do not have Name plate of transformer available. The drawing it was not correct. It is Two Winding 11/0,48 kV Transformer.
prc: Could you tell me where I could ask about this issue?
Here you can find the SLD.
Link
Thanks
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
-JFPE
RE: Two Incoming Feeders connected to secondary of Two Winding Transformer.
Your system connection arrangement has the inherent tendency to cause circulating current. You cannot connect two sources to the transformer like you have shown in the sketch.
The branching like this is fine for the load side, but not on the source side. That too, the kind of sources, where the generation cannot remain constant.