Proje sadece eviriciyi değil, aynı zamanda kaçak akım rölesini de gösteriyor.

This is a very common Turkish pattern meaning not only ... but also ....

So:

• sadece eviriciyi değil = not only the inverter
• aynı zamanda kaçak akım rölesini de = but also the residual-current relay / leakage current relay

The full structure is:

X sadece ... değil, aynı zamanda ... de ...

It works much like English not only X, but also Y.

Değil often means not / is not, but in this pattern it is part of the fixed contrast structure:

sadece ... değil = not only ...

So here, değil is not negating the whole sentence. It is helping build the expression not only X.

That is why the sentence still has a positive verb at the end:

• gösteriyor = is showing / shows

So the idea is not The project does not show the inverter.
It is The project shows not only the inverter, but also ...

That de adds the meaning of also / too.

In this construction, Turkish often uses:

• sadece ... değil
• aynı zamanda ... de

So kaçak akım rölesini de means the leakage current relay as well / also the leakage current relay.

This de is an enclitic particle, so it is written separately:

• correct: rölesini de
• not: rölesinide

These are accusative endings, used because these nouns are definite direct objects.

The verb is göstermek = to show.
What is the project showing? Specific things:

• eviriciyi = the inverter
• kaçak akım rölesini = the leakage current relay

In Turkish, a definite direct object usually takes the accusative ending.

Breakdown

• evirici
  • -yi → eviriciyi
• rölesi
  • -ni → rölesini

If the objects were indefinite or more general, Turkish might leave off the accusative:

• Proje bir evirici gösteriyor. = The project shows an inverter.

But here the sentence is about specific items, so the accusative is used.

Because kaçak akım rölesi is a Turkish noun compound.

In Turkish, compounds like this often work as:

• kapı kolu = door handle
• araba kapısı = car door
• kaçak akım rölesi = leakage current relay

The second noun gets a compound marker, usually -(s)ı / -(s)i / -(s)u / -(s)ü.

So:

• röle = relay
• kaçak akım rölesi = leakage current relay

Then, when that whole compound becomes a definite direct object, it takes the accusative ending too:

• kaçak akım rölesi
  • -ni → kaçak akım rölesini

So -si is part of the compound, and -ni is the accusative ending.

Here, aynı zamanda means also / at the same time / as well, but in this kind of sentence it is best understood as part of the expression not only ... but also ....

Literally:

• aynı = same
• zaman = time
• -da = in/at

So literally it is something like at the same time, but in many sentences it functions idiomatically as also or in addition.

In this sentence, it helps create a more formal, clear but also meaning.

Gösteriyor is the present continuous form, but in modern Turkish it is also very often used for a general present meaning, especially in spoken and everyday written language.

So:

• gösteriyor = is showing / shows
• gösterir = shows / would show / generally shows, often a bit more formal, habitual, or context-dependent

In a sentence like this, gösteriyor sounds very natural if someone is describing what a diagram, project, screen, or interface shows.

So this sentence can mean something like:

• The project is showing not only the inverter, but also the leakage current relay.
• or more naturally in English, The project shows not only the inverter, but also the leakage current relay.

Because Turkish normally puts the main verb at the end.

The basic word order is often:

subject + object + verb

Here:

• Proje = subject
• sadece eviriciyi değil, aynı zamanda kaçak akım rölesini de = object phrase
• gösteriyor = verb

So the sentence ends with the action, which is very normal in Turkish.

Yes, that is close to the Turkish word order.

A very literal mapping would be:

• Proje = the project
• sadece eviriciyi değil = not only the inverter
• aynı zamanda kaçak akım rölesini de = but also the leakage current relay too
• gösteriyor = shows / is showing

But natural English rearranges it to:

The project shows not only the inverter, but also the leakage current relay.

This is a good reminder that Turkish and English organize information differently, especially because Turkish places the verb at the end.

Yes. In many contexts, sadece, yalnızca, and sometimes yalnız can all mean only / just.

For example:

• Proje sadece eviriciyi değil...
• Proje yalnızca eviriciyi değil...

Both are natural.

However, sadece is very common and straightforward, so it is often the easiest choice for learners.

No. They look the same, but they are different things.

In this sentence:

• de is a separate word meaning also / too
• it is written separately: rölesini de

The locative ending:

• -de / -da means in / on / at
• it is attached to the noun: evde = at home, masada = on the table

So:

• rölesini de = the relay too
• rölede = in/on/at the relay depending on context

They are different grammatical items.

Turkish does not have a direct word for the.

Instead, definiteness is often shown by context and, with direct objects, by the accusative ending.

That is why:

• eviriciyi is understood as the inverter
• kaçak akım rölesini is understood as the leakage current relay

So Turkish often expresses what English does with the by using case endings and context rather than an article.