electrolytic caps in toaster oven

[Jamie Morken]

Hi all,

How well do SMT electrolytics (the silver can type) stand up to heat
during soldering in a toaster oven? I have had to rework a part on a
small board and it has been in the toaster oven 4 times now The
board is looking a little charred but everything still works, but I am a
bit concerned about the internals of the caps.. thanks,

cheers,
Jamie Morken

 

[Robert Baer]

Robert Baer wrote:

Jamie Morken wrote:

Hi all,

How well do SMT electrolytics (the silver can type) stand up to heat
during soldering in a toaster oven? I have had to rework a part on a
small board and it has been in the toaster oven 4 times now The
board is looking a little charred but everything still works, but I am a
bit concerned about the internals of the caps.. thanks,

cheers,
Jamie Morken

One could get the manufacturers spec sheet on the particular type and
model of capacitor in question.
That is to say, each manufacturer has their own manufacturing and
quality standards, and ther are different models within a give type.
For example, there are many models of aluminum capacitors, and each
one has their own temperature rating, recommended SMT temperature
profile, etc.
BUT.
The best way is to actually test some in the environment you use.
Take ten or more and mount them on a PCB with test leads (say common
ground (negative side) and seperate test points; maybe even guild the
lilly and put a diode and resistor in series to common charging voltage.
Heat them, cool them, charge them to rating, let them sit for 10
hours, discharge each one with resistor and test capacitance and ESR.
repeat 20 times or until 2-3 die.
Make a record of all readings, heat times, etc.

Ig you change brands, types or models, start again.

I mentioned 20 times, because i think the caps will die long before
then.

 

[Robert Baer]

Jamie Morken wrote:

Hi all,

How well do SMT electrolytics (the silver can type) stand up to heat
during soldering in a toaster oven? I have had to rework a part on a
small board and it has been in the toaster oven 4 times now The
board is looking a little charred but everything still works, but I am a
bit concerned about the internals of the caps.. thanks,

cheers,
Jamie Morken

One could get the manufacturers spec sheet on the particular type and
model of capacitor in question.
That is to say, each manufacturer has their own manufacturing and
quality standards, and ther are different models within a give type.
For example, there are many models of aluminum capacitors, and each
one has their own temperature rating, recommended SMT temperature
profile, etc.
BUT.
The best way is to actually test some in the environment you use.
Take ten or more and mount them on a PCB with test leads (say common
ground (negative side) and seperate test points; maybe even guild the
lilly and put a diode and resistor in series to common charging voltage.
Heat them, cool them, charge them to rating, let them sit for 10
hours, discharge each one with resistor and test capacitance and ESR.
repeat 20 times or until 2-3 die.
Make a record of all readings, heat times, etc.

Ig you change brands, types or models, start again.