I don't think I understand your question. But, the three lugs you are pointing to are the three positive 5 volt DC outputs. DO NOT connect the AC input power there. AC power connects to the left side of the converter.

Each of your 5 volt output circuits  (on the left side of the converter) will have one 5v positive (+V) wire and one Com (-) wire.

ah so only one v+ and one v- will be used to connec to terminals ? and averything els wil be connected to the terminals servo's/lights ?

V- IS NEGATIF ? v+ IS POSITIF ? so there are 3 V- AND 3 V+ ?  3 channels .

Based on the link that DJ posted I thought you had three 5 volt dc positive lugs  and three com lugs  I took a closer look at the picture you posted and your's only has 2 each. I don't know why there is a difference if you got what DJ links to. Would you mind posting the link you bought your converter from? I would like to take a closer look at it. It could be as simple as what's available to me here in the United States opposed to you from your country. Also could you take a picture of the nameplate mounted on the converter that has all the specifications on it and post that also?

@dave

here's the link from the converter . if its the wrong one no worry's . they are cheap . i cant se any with 3 outlets . i cant by from amazon.com, cause they dont have paypal . [url=https://www.amazon.nl/dp/B0BX2L1HS6?ref=ppx_yo2ov_dt_b_product_details&th=1]converter

@dave

i found one like dj and bouth it . in UK .

converter

Hey dude - the gnd and +5v are labeled here. There are 2 connections for each, but they're the same and shared.

Your mains power input is here...

And you can adjust (fine-tune) the 5v output with the dial here

OK, thanks for the pictures. You have the converter you expected with the exception of only two DC outputs (V+ and Com). Now I know what you have for sure.

I'm going to sit down a little later on and try to draw out a simple schematic of where to attach your wires. Seems that writing about it has its challenges. No worries.

hi dj/dave

thanks you for the pictures . so V- is negative v+ is positive .