# How to start an electronic project?

#### onebrain2

Joined Apr 3, 2016
9
I am Angolan citizen who is working in electronic field as a electronic technician repair, there are a lot of questions in my mind, i will post one by one here so you can help me, i would like to build a dc power regulator with input of 18V and a desired output 12V to work with a power inverter of 1000W and 12V in input.

#### blocco a spirale

Joined Jun 18, 2008
1,546
You will need a DC-DC converter with a 12V output at around 100A if you want to get 1kW out of the following inverter.

It would be no more difficult to build a 1kW inverter with an 18V input..... which is by no means easy.

#### tcmtech

Joined Nov 4, 2013
2,867
Where is the 18 volts coming form and what are y9ou intending to do with the power at the end?

#### mcgyvr

Joined Oct 15, 2009
5,394
please pick a different starting project.
That is a horrible project for a beginner..

Try something with very low voltage and low current..

#### ScottWang

Joined Aug 23, 2012
6,982
So you want to build two projects, the first one is 18V to 12V regulator, and the second one is Io=12V/1000W=83.3A inverter (eff=80%, Ii=104.2A, eff=90%, Ii=92.6A)?

You want to build both or just the regulator?

What is the load for inverter?

#### onebrain2

Joined Apr 3, 2016
9
it is coming from a solar panel wich i can´t see the specification just measure the output power

#### onebrain2

Joined Apr 3, 2016
9
So you want to build two projects, the first one is 18V to 12V regulator, and the second one is Io=12V/1000W=83.3A inverter (eff=80%, Ii=104.2A, eff=90%, Ii=92.6A)?

You want to build both or just the regulator?

What is the load for inverter?

i need to use the inverter to work with my domestic stuffs in my house, so total load power maybe 800W, i need first regulate the power then use it with the inverter wich i already have.

#### onebrain2

Joined Apr 3, 2016
9
Where is the 18 volts coming form and what are y9ou intending to do with the power at the end?
it is coming from a solar panel, wich i do not have the specification because someone erased

#### GopherT

Joined Nov 23, 2012
8,012
it is coming from a solar panel wich i can´t see the specification just measure the output power
Did you measure the solar panel voltage with a load connected to it or "open voltage" - with nothing connected?

#### tcmtech

Joined Nov 4, 2013
2,867
i need to use the inverter to work with my domestic stuffs in my house, so total load power maybe 800W, i need first regulate the power then use it with the inverter wich i already have.
Okay. First thing to do would be to dump the solar panel power into an adequately sized battery (12 volt 100+Ah deep cycle set) with some sort of charge controller being a solar panel by itself sill not support any kind of power inverter load.

Or directly grid tie the solar panel and pirate back feed the power to your whole house thus cutting your electric bill down without the hassle of dealing with batteries, charge controllers and hooking and unhooking things from the inverter as the power is available.

All you need to know about DIY GTI builds can be found here. http://www.electro-tech-online.com/forums/alternative-energy/

Just some stuff to research and think about.

#### onebrain2

Joined Apr 3, 2016
9
Where is the 18 volts coming form and what are y9ou intending to do with the power at the end?
Did you measure the solar panel voltage with a load connected to it or "open voltage" - with nothing connected?

yes, the 18V is with open voltage, nothing connected

#### GopherT

Joined Nov 23, 2012
8,012
yes, the 18V is with open voltage, nothing connected
Then connect it to a load and measure the voltage. It may drop significantly (e.g. 12 V).

#### ScottWang

Joined Aug 23, 2012
6,982
i need to use the inverter to work with my domestic stuffs in my house, so total load power maybe 800W, i need first regulate the power then use it with the inverter wich i already have.
Inverters should be have Vi, Ii, Wi, Vo, Io, Wo, what are yours?

#### tcmtech

Joined Nov 4, 2013
2,867
yes, the 18V is with open voltage, nothing connected
And how big is this solar panel?

What's it short circuit current?

Can it put out over 800 watts to begin with?

#### onebrain2

Joined Apr 3, 2016
9
Inverters should be have Vi, Ii, Wi, Vo, Io, Wo, what are yours?
ok, i will check out this units then tell you

#### onebrain2

Joined Apr 3, 2016
9
And how big is this solar panel?

What's it short circuit current?

Can it put out over 800 watts to begin with?

the solar panel doesn´t have a specification paper, someone removed it. but i will know how many cells it have then tell you.

#### tcmtech

Joined Nov 4, 2013
2,867
A rough estimate of its dimensions and wire sizes would tell us the basics.

Unless this panel takes up half the roof of your house I doubt it will put out 800+ usable watts.

#### #12

Joined Nov 30, 2010
18,216
the solar panel doesn´t have a specification paper, someone removed it.
So measure its output...or are you planning on designing and building a 1000 watt inverter without owning a meter?

#### tcmtech

Joined Nov 4, 2013
2,867
Sure ! Why not? A little detail like that will never stand in the way of a guys dreams of energy independence you know!