How to edit transformer

How to edit transformer specs (rs rp ls lp np ns lm) in schemat ?

Welcome to the forum.

The schematic symbol is the same for all transformers of a type, like single primary and secondary. The details of turns ratio etc are not required.

Perhaps you are referring to the model in spice?
Please clarify.

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I started to use kicad for simulation only (understanding circuit working) ,for that i need to put all the specs of the circuit ,not just a schematic .
Thank you

I wondered if this was in the right section when I initially read it. Moved.

Create a subcircuit for your transformer and attach it to the transformer sybol.

The subcircuit may look like:

.subckt transformer1 in1 in2 out1 out2 Lin=100u Lout=100u Rin=1 Rout=1
* inductances
Li in1 intin {Lin}
Lo out1 intou {Lout}
* coupling factors
K1 Li Lo 1
* series resistances
Ri intin in2 {Rin}
Ro intou out2 {Ro}

The call to this subcircuit then may be

xtran 1 2 3 4 transformer1 Lin=100u Lout=900u Rin=1 Rout=3

1, 2, 3, and 4 are the pins of your transformer symbol. gives a hint where to place the part of the x line
transformer1 Lin=100u Lout=900u Rin=1 Rout=3
of your call to the subcircuit (put it into the Spice_Model field).

Please have a look at, especially see the equivalence of L and n. Real data have to be found in the transformer data sheet.

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