See if my diagram is correct (some toggle switchs + relay)

Hi guys, in last 2 days, i learned with help of forum users how make circuit with 2 position switch and 3 position switch + relay..

I am making painel for ground station (Drone Live video), it will have several switchs..

This time, lets concentrate on 3 first switchs.. After make it work, will work on next switchs

Its have somethings wrong, i did all i was able to do with actual knowlodge that i have (little)..

My goal is

1º Switch (Power): It will power on or power off all circuit (when on green led will power on)
2º Switch (Change Energy Source): i can choose to power on all circuit 3 different sources: Internal Battery (12v), Car (12v) or outlet power source (12v), each position will power on different led
3º switch (change internal battery source from 1 to 2), also will power on different led for each position

Observation: All power sources will pass through 1 fuse for protection

See my diagram:


If something missing or wrong on these 3 first switchs, please help me do this right.. More simple solution is better, because i will have too much work soldering and how much simple, more organized it is (space gain too)..

Thanks verry much !!!

It seems that here the 4-pin RGB LED has a common anode (connected to +), right?

On the other hand, if the board could be supplied by different 12V sources and 11V is good for the board, placing a forward diode in series with each source and joining the diodes at the other side, the board will be supplied automatically by the highest voltage available from one of the different power supplies.

KerimF said:

It seems that here the 4-pin RGB LED has a common anode (connected to +), right?

Click to expand...

Yes, just connect + on this pin, and - with 1 k resistor on one of 3 last pins to power on each led..

Ok, so the common node (ground) on your board has to be the positive terminals of all supplies, right?

And do you think, as I pointed it out earlier, diodes could be used here to simplify the selection of the source?
The drawback of this idea is that the board gets (Vcc_highest - Vdiode).

KerimF said:

Ok, so the common node (ground) on your board has to be the positive terminals of all supplies, right?

And do you think, as I pointed it out earlier, diodes could be used here to simplify the selection of the source?
The drawback of this idea is that the board gets (Vcc_highest - Vdiode).

Click to expand...

so the common node (ground) on your board has to be the positive terminals of all supplies, right?
Answer: Yes, i will invert, as led use negative to power on each led color, i will connect all to positive, and will control each connection using negative instead positive

About automatic source, would be really interresting, but its crucial part of circuit, it never can fail, because if fail will shut down ground station, i will lost link with drone = Disaster.. Heheheh
I prefer use switchs to have better control over that.. i think that it also more simple to do (circuit)..

In my opinion, using diodes is much more reliable than using switches and it takes less space besides being automatic But this diode method cannot be implemented if the diode voltage drop (about 0.75V) is an acceptable for your application (that you only know it). Another drawback, since you like using colored LED :wink:, there will be no indication of the strongest source that supplies the board (though this can be solved by adding for each source an NPN transistor that you don't like it :wink: ).

I prefer make it more simple (circuit), because i dont have too much knowlodge, i also already have painel done, it was made using cutted acrylic + led backlight + cutted vinyl on front, and have switch with names (backlight), i also wont be able to see what source is using.. i spent too much time to make this painel with finishes, now it time for circuit, no more design..
Understand why i prefer switchs ? in future i can plan use automatic with version 2.0 of my ground station..

You are right. I didn't know you have already the panel.

I am not sure about the functions of the 5 terminals of the square (C, R and the other three unamed ones) below 3P switch.

KerimF said:

You are right. I didn't know you have already the panel.

I am not sure about the functions of the 5 terminals of the square (C, R and the other three unamed ones) below 3P switch.

Click to expand...

Its simple relay,
C is Closed
R is Relay (when relay is energized)
3 pins are: Positive negative and in middle contact that go to R or C (depending if its energized or not)

Understood ?

I think I got it:
C is normally connnected to the middle contact (relay not energized). In this case R is open.
When the relay coil (pin 1 and pin 3 at the right side) is energized, C is open and R is closed.

Extra note:
For the relay coil, it may be better, for the switch, adding a general purpose diode in reverse and parallel with it. So when the coil is off, its stored energy (current) can be discharged via the diode instead of rising its voltage till a small spark discharge it. If the coil current is small or the contacts of the switch are robust, the effect of the spark may be negligible.

About analysing the circuit:
First, no matter at which position P3 is, its red LED is on if the 12V power supply is active... Is this ok for you?

KerimF said:

I think I got it:
C is normally connnected to the middle contact (relay not energized). In this case R is open.
When the relay coil (pin 1 and pin 3 at the right side) is energized, C is open and R is closed.

Extra note:
For the relay coil, it may be better, for the switch, adding a general purpose diode in reverse and parallel with it. So when the coil is off, its stored energy (current) can be discharged via the diode instead of rising its voltage till a small spark discharge it. If the coil current is small or the contacts of the switch are robust, the effect of the spark may be negligible.

About analysing the circuit:
First, no matter at which position P3 is, its red LED is on if the 12V power supply is active... Is this ok for you?

Click to expand...

All is correct about relay.

C is when relay is not energized and R is when relay is energized, middle pin go to R or C depending if relay is energized or not, about P3, it have to work this way: Internal Battery (12v) (1º position switch, led green only), Car (12v) (2º position switch, led blue only) or outlet power source (12v) (3º position switch, red green only)

if aways red on, i wont know what source it came, and can mistake about postion and switch to source that not exist in moment, causing circuit shutdown..

Sorry for not being clear (post #10)... I was talking about YOUR ACTUAL diagram (on post #1) when I said:

no matter at which position P3 is, its red LED is on if the 12V power supply is active

Click to expand...

Didn't you notice it too?

i had not noticed until you talk, but in my diagram, i think that have too many errors, can you help me making it right ?! Thanks

It seems I got cold (yes even in summer), sorry. I hope I will recover soon.

KerimF said:

It seems I got cold (yes even in summer), sorry. I hope I will recover soon.

Click to expand...

Ok, this happens. hehehe. In brazil dont have too much difference when is summer or winter, all time is hot..
about project, if someone can help to finish this first step, would be increadible.

Any help is welcome.

Thanks for all

Hi Felipe,

I didn't expect my weakness would be very serious.
I had to go to hospital and stay in for several days (it cost me a fortune since we live a war time).
Now, I am home again and I am recovering gradually.

About your diagram, please let me know if it was fixed.
If it wasn't fixed yet, I will draw and upload my solution (concerning the 3P switch).

Kerim

KerimF said:

Hi Filipe,

I didn't expect my weakness would be very serious.
I had to go to hospital and stay in for several days (it cost me a fortune since we live a war time).
Now, I am home again and I am recovering gradually.

About your diagram, please let me know if it was fixed.
If it wasn't fixed yet, I will draw and upload my solution (concerning the 3P switch).

Kerim

Click to expand...

Hi, hope you recovered and now stay with good health... About war days, what is your country ?!

I had no progress on my diagram yet, your help would be verry welcome..

Thanks for your attetion !

Hi Felipe,

So I will draw my solution for you.
I assume:
(1) There are 4 different supplies (PS1 to PS4).
(2) When a supply is selected, one of four LEDs is on (L1 to L4).

The first 3 switches will be used; two of 2P type and one of 3P type.
There will be no need for a relay.
The off position of the 3P switch turns off the whole panel (no supply is selected and L1 to L4 are off).

Kerim

About my location, it seems you didn't hear yet of Syria
I live in Aleppo city. It is now surrounded by about 100,000 foreign well-armed mercenaries sent from more than 25 countries to take it over (then Syria).
But by the media, billions of people in the world were made to believe that Syrians live a civil war or a revolution to cover up all the terrorist crimes of these foreign long dark beards (UN calls them rebels!!!) sent to Syria gradually since more 2 years. But I still believe that my Father in Heaven will save Syria sooner or later though more than half of the world decided attacking it since March 2011 (That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it).