Author Topic: PCB rework  (Read 1045 times)

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Offline R_G_B_

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PCB rework
« on: October 25, 2015, 10:29:00 am »
I was doing some PCB rework on a graphing multi meter.

I used a hot air station 240 degree C. Had a little success. I decided to up the temperature to 320   degree as it was taking a little too long to heat the solder on the board. Now the board does not switch on I am concerned i may have damaged components.

I did try to avoid heating  the components. I checked there is 5V reference going to the components.

 I see re flow  ovens operate at 250. So it looks like i went to high in temperature  :palm:

 |O

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Offline Jeroen3

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Re: PCB rework
« Reply #1 on: October 25, 2015, 12:19:10 pm »
With hot air you can increase the temperature if you need a larger area to be heated. As you'd need to desolder a SMD mosfet with heat plane.
Since you can change the airflow the actual temperature on the board surface may be less than that the nozzle sensor measures.

You can get hot air stations with an extra temperature sensor to compensate this.

What type of components where in the heated area?
 

Offline R_G_B_

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Re: PCB rework
« Reply #2 on: October 25, 2015, 03:40:48 pm »
With hot air you can increase the temperature if you need a larger area to be heated. As you'd need to desolder a SMD mosfet with heat plane.
Since you can change the airflow the actual temperature on the board surface may be less than that the nozzle sensor measures.

You can get hot air stations with an extra temperature sensor to compensate this.

What type of components where in the heated area?

Resistors, capacitors, transistor ROM ram CPU MOV diodes etc....


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