Kad god zbrinete električni aparat, koristite odvojeno sakupljanje.

Kad means when, but kad god means whenever or any time that.

So:

• Kad zbrinete električni aparat... = When you dispose of an electrical appliance...
  This can sound like one specific occasion.
• Kad god zbrinete električni aparat... = Whenever you dispose of an electrical appliance...
  This clearly gives a general rule or instruction.

That fits the tone of a public notice or environmental instruction.

Zbrinete is from the verb zbrinuti.

This verb often means something like:

• to take care of
• to deal with properly
• in official/environmental language, to dispose of properly

The form zbrinete is 2nd person plural present. With kad god, Serbian often uses the present form this way to talk about repeated future situations:

• Kad god zbrinete... = Whenever you dispose of...

So even though English may feel more future-oriented, Serbian naturally uses this kind of present form in time clauses.

It is understandable, but it sounds fairly formal and administrative in this sentence.

In everyday speech, people might more often say something like:

• baciti aparat
• odložiti aparat
• rešiti se aparata
  depending on context

But on official notices, instructions, recycling information, and public signage, zbrinuti sounds appropriate because it suggests proper handling/disposal, not just throwing away.

Because of the context.

The form koristite can look the same as:

• present tense: you use
• imperative: use! (addressing more than one person, or one person formally)

In this sentence, it is clearly an instruction, so it is understood as the imperative:

• koristite odvojeno sakupljanje = use separate collection

This is very common in Serbian public instructions: the language addresses the reader politely or collectively with the 2nd person plural imperative.

Because električni aparat is the direct object of zbrinete, so it is in the accusative case.

But here is the key point:

• aparat is masculine singular inanimate
• for masculine inanimate nouns, accusative singular = nominative singular

So:

• nominative: električni aparat
• accusative: električni aparat

No visible change happens.

If the noun were masculine and animate, you would see a different accusative form.

Because Serbian often uses the generic singular to talk about a whole class of things.

So električni aparat here does not mean one specific appliance. It means any electrical appliance, in a general sense.

English does something similar:

• Whenever you dispose of an electrical appliance...

So the singular is completely natural here.

Because Serbian does not have articles like English a / an / the.

So Serbian simply says:

• električni aparat

and the listener understands from context whether it means:

• an electrical appliance
• the electrical appliance
• electrical appliances in a generic sense

Here, the generic meaning comes from the whole sentence, especially kad god.

It is a noun phrase meaning separate collection.

Breakdown:

• sakupljanje = collecting / collection
  (a verbal noun, neuter singular)
• odvojeno = separate / separately separated in this fixed administrative phrase

In this sentence, the whole phrase is the direct object of koristite:

• koristite odvojeno sakupljanje = use separate collection

Because sakupljanje is neuter singular, its accusative form is the same as the nominative, so again there is no visible change.

Yes. Serbian word order is flexible.

For example, this would also be possible:

• Koristite odvojeno sakupljanje kad god zbrinete električni aparat.

The meaning stays basically the same.

The version with the kad god clause first is common in formal instructions because it sets up the situation first:

• Whenever this happens, do this.

So the chosen order sounds very natural for a notice or guideline.

Because the sentence begins with a dependent time clause:

• Kad god zbrinete električni aparat = Whenever you dispose of an electrical appliance

Then comes the main clause:

• koristite odvojeno sakupljanje

In Serbian, it is normal to separate that introductory clause with a comma, just as in English:

• Whenever you dispose of an electrical appliance, use separate collection.

Yes, definitely.

Several things make it sound official:

• kad god gives it a general rule-like tone
• zbrinete is more formal than everyday bacite
• odvojeno sakupljanje is standard environmental/recycling terminology
• koristite in the imperative is typical of public instructions

So this sounds like something you would read on:

• a recycling notice
• packaging
• a municipal waste-disposal guide
• an appliance manual or label