Burnt PCB board from burnt components , does it have carbon in the PCB?

[Billy Mayo]

At work there is PCB boards that are BURNT because of the components got very hot and burnt to black themselves

How do you know is there is carbon in the PCB board now? my manager calls it carbon substrate

When the PCB board is BURNT , and you put new components ontop of the burnt pcb , what happens?

Is the BURNT pcb board a parallel path for current?

Is the BURNT pcb board have resistance? does it add resistance to the traces where it's burnt?

My manger used a Fiber glass eraser to erase the burnt PCB board, but it just makes a PIT in the PCB but it's still burnt

My manager said you can lay components over the BURNT PCB board because the BURNT PCB board doesn't do anything to the circuit, is this true?

The BURNT PCB board does touch other pads and traces

It's a double sided PCB board

If the BURNT PCB board didn't touch other pads or traces would this be true that it won't do anything and you can lay new components ontop of it and solder new ones in place even tho it's burnt underneath?

 

[alec_t]

My manager said you can lay components over the BURNT PCB board because the BURNT PCB board doesn't do anything to the circuit, is this true?

Don't you trust what your manager says?

 

[Ian Rogers]

The BURNT PCB should go in the bin. ( Sorry!!! Responsibly disposed of)

 

[dr pepper]

'Carbon substrate' isnt what I'd call it.
Charred pcb is probably ok at low volatges and low frequencies, if the area was subjected to radio frequencies or high voltage then it might well conduct and affect the operation of the circuit.
I suspect however this circuit board is a power supply board.

 

[kubeek]

Maybe you should try looking up what are PCBs made of. Generally it is glass cloth bonded with some kind of epoxy. Obviously, the epoxy being an organic compound, when it gets burnt most of the residue is carbon.

As dr peeper said, you might be able to use the charred pcb, it depends on how badly it is burnt, what components are in that area and how the charring will affect the circuit due to excessive leakage.

Another point would be that the board could start delaminating, so traces could start to peel off and also it will lead to the pcb holding moisture between the layers which again is not a good thing.

 

[large_ghostman]

At work there is PCB boards that are BURNT because of the components got very hot and burnt to black themselves

How do you know is there is carbon in the PCB board now? my manager calls it carbon substrate

When the PCB board is BURNT , and you put new components ontop of the burnt pcb , what happens?

Is the BURNT pcb board a parallel path for current?

Is the BURNT pcb board have resistance? does it add resistance to the traces where it's burnt?

My manger used a Fiber glass eraser to erase the burnt PCB board, but it just makes a PIT in the PCB but it's still burnt

My manager said you can lay components over the BURNT PCB board because the BURNT PCB board doesn't do anything to the circuit, is this true?

The BURNT PCB board does touch other pads and traces

It's a double sided PCB board

If the BURNT PCB board didn't touch other pads or traces would this be true that it won't do anything and you can lay new components ontop of it and solder new ones in place even tho it's burnt underneath?

You actually asked your manager!! I bet he gives you funny looks or suddenly needs the loo when you appear lol.
Apart from the obvious bin it, if a pcb board was conductive how good would it be? carbon can be conductive but is the biurnt material you describe conductive?? did you test it or reach for the laptop to ask?

 

[large_ghostman]

The BURNT PCB should go in the bin. ( Sorry!!! Responsibly disposed of)

Or sold on ebay

 

[ronv]

In general it does not make a PCB more reliable to repair burned traces. Maybe what you could do it keep track of which trace, capacitor or IC blows on your boards. Since electronics are very reliable you will probably find a pattern of the same capacitor type or location, IC's in backwards or solder shorts downstream from the blown trace. With enough data you will learn where to look for the problem before you need to zap it.

 

[KeepItSimpleStupid]

I repaired one amplifier that was extensively damaged. The film resistors "puddled" on the board. It kinda had to be repaired because it was borrowed by the client. Five repair shops turned it down. Direct short on a 250 W/channel amp used in a disco.

I did, however use epoxy to repair the burnt board.

Here, however is a company that can repair a broken corner of a PCB: **broken link removed**

 

[kubeek]

All technicians IPC certified with over 285 years of circuit board repair experience.

I just wonder how those technicians feel after working for 285 years in the industry..
Must have been a hell of a job back in 1729

 

[large_ghostman]

I am sorry if you took offense at anything I posted! I humbly apologize for hurting any feelings you may or may not posses.
LG

Mod Edit!!! One more out burst LG and I'll ensure you don't!!!

 

[audioguru]

Is it a coincidence that one minute ago I was reading Billy's thread about applying a high current to a pcb to locate a short and we said DONT DOO IT because it would BURN things?
And now he talks about a burnt pcb.
Told ya so!

 

[large_ghostman]

Is it a coincidence that one minute ago I was reading Billy's thread about applying a high current to a pcb to locate a short and we said DONT DOO IT because it would BURN things?
And now he talks about a burnt pcb.
Told ya so!

Any chance you could mention not licking the ends of a cable plugged into 230V??

 

[KeepItSimpleStupid]

That's reserved for testing 9V batteries or under the heading "Unconventional Test Equipment". Been there. Done that. Long ago.

 

[large_ghostman]

Ive tried that! funny thing is you have to do it twice!! I bet you did as well

 

[large_ghostman]

I am saving for a decent antenna, maybe we should have bets as to when the posts will change to job seeking advice

 

[Ian Rogers]

Thread Closed!!