Circuit drawing double side.

[Gregory]

I have tried to get a circuit diagram for my C I G 195 mig welder but with no luck.
I am going to try and draw a circuit I have never don this . I will require help from time to time.
Can you tell me how do you draw a double sided board circuit.
This is the circuit board in question .
I have posted this post in the wrong area.
I do not know how to move this post to PCB.
COULD someone move this post
Thank you

 

[Pommie]

It is probably best to work out the schematic first and then use one of the free pcb design programs to design a new board.

Mike.

 

[Gregory]

Do I draw one side then draw the other side.

 

[Gregory]

I need the circuit for me and others to fault the board

 

[rjenkinsgb]

The schematic will be the whole circuit of the board in one go.

The two sides of a board are generally to make it more compact and allow different connections to cross each other (on opposite sides).

 

[Gregory]

How do I join the both sides in a circuit drawing.
Could you show me how it is done

 

[rjenkinsgb]

Just follow the connection from where it leaves one component pin until it arrives at the next, regardless of which side it is or if it changes sides.

Spread things out well as you draw. You will probably end up re-drawing sections as you fill in more connections and the signal "flow" through different parts starts to make some sense, or when you get too many crossing connections on the drawing.

 

[Gregory]

I do not under stand .
And what free cad system can I use

 

[rjenkinsgb]

I'd use pencil and paper until you have a complete drawing. It's easier to erase and change as you go!

The Designspark programs from RS components are free; there is one for electrical / wiring and another for electronics schematics and PCB creation.

https://www.rs-online.com/designspark/our-software

 

[Pommie]

If you take good pictures of the board from top and bottom and flip the bottom picture left to right, you can draw a grid on them so you can easily see how connections go through the board. Can you draw and read a schematic?

Mike.

 

[Gregory]

I will attempt to do that . Will then post a reply.
Thank you Greg

 

[Gregory]

Because the CAD drawing is a windows I can not open it up in my I pad Can you assist me with this problem

 

[DerStrom8]

I hate to say it but I think you're way out of your league. You're not going to be able to achieve what you want based on the level of experience you appear to have, based on your questions. Your best bet would probably be to buy a new welder, or at least a new control board.

 

[Gregory]

I can not afford a new welder .
I can not find a new board. May be you can help me
Thank you Greg

 

[Pommie]

What is wrong with the existing board? Maybe someone can help fixing it.

Mike.

 

[Gregory]

If I describe the problem could you help me

 

[Pommie]

Maybe. Problems like "it doesn't work" tend to be the hardest to fix.

Mike.

 

[rjenkinsgb]

It is a very old circuit board and has been repaired several times before, resulting in some damage to pads.

It looks like the two C122D thyristors have been changed before. I'd try swapping those and the two stud diodes on the same heatsinks.
It's a gamble but they are the main "high power" devices so most likely to fail if something is overloaded or overheated.

 

[Gregory]

I have hand sketched the underside of the board and I will do the other side with components .
Could you check it out.

 

[DerStrom8]

If this is a multi-layer board then you are completely out of luck, because it's nearly impossible to know what the inner layers look like.

Have you ever heard the phrase "beyond economical repair"? Because I think that describes your welder, unfortunately.