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High-temperature cap replacement

C

Clifford Heath

Jan 1, 1970
0
The control chip in our oven has gone haywire, and I suspect
the supply filter cap, a 220uF 25VW electro with a 125C temp
rating. It's in a hot place! It filters the supply generated
through two wirewound resisters dropping from 240V.

Is there a better replacement cap I can get for this purpose?
Do tantalum caps withstand this temp better?

Otherwise where might I find (in Melb) a 125C rated cap without
having to pay $10 in postage from Farnell etc? It doesn't seem
to be the kind of thing stocked by the usual suspects.

Clifford Heath.
 
D

David L. Jones

Jan 1, 1970
0
Clifford Heath said:
The control chip in our oven has gone haywire, and I suspect
the supply filter cap, a 220uF 25VW electro with a 125C temp
rating. It's in a hot place! It filters the supply generated
through two wirewound resisters dropping from 240V.

Is there a better replacement cap I can get for this purpose?
Do tantalum caps withstand this temp better?

Otherwise where might I find (in Melb) a 125C rated cap without
having to pay $10 in postage from Farnell etc? It doesn't seem
to be the kind of thing stocked by the usual suspects.

Clifford Heath.

Rockby have some 125 deg rated electros:
http://www.rockby.com.au/searchres.cfm?searchkey=125+deg&imageField.x=0&imageField.y=0

No exact match, but a couple of the 68uF 40V axial jobs might do the trick
if they fit.

Rockby are in Clayton.

Dave.
 
E

Eeyore

Jan 1, 1970
0
Clifford said:
The control chip in our oven has gone haywire, and I suspect
the supply filter cap, a 220uF 25VW electro with a 125C temp
rating. It's in a hot place! It filters the supply generated
through two wirewound resisters dropping from 240V.

Is there a better replacement cap I can get for this purpose?
Do tantalum caps withstand this temp better?

Otherwise where might I find (in Melb) a 125C rated cap without
having to pay $10 in postage from Farnell etc? It doesn't seem
to be the kind of thing stocked by the usual suspects.

Not likely either sadly. 105C is good enough for most apps.

Graham
 
C

Clifford Heath

Jan 1, 1970
0
David said:
Rockby have some 125 deg rated electros

Perfect, David! Thanks for the pointer.

Still interested if anyone can answer whether other types might suit.
 
F

Franc Zabkar

Jan 1, 1970
0
The control chip in our oven has gone haywire, and I suspect
the supply filter cap, a 220uF 25VW electro with a 125C temp
rating. It's in a hot place! It filters the supply generated
through two wirewound resisters dropping from 240V.

Is there a better replacement cap I can get for this purpose?
Do tantalum caps withstand this temp better?

Otherwise where might I find (in Melb) a 125C rated cap without
having to pay $10 in postage from Farnell etc? It doesn't seem
to be the kind of thing stocked by the usual suspects.

Clifford Heath.

Look for a capacitor with a solid dielectric.

This series is targeted at industrial high temperature, automotive,
military and space applications:
http://www.vishay.com/docs/28355/28355.pdf

• Extremely long useful life: 20 000 hours at 125 °C
• Extended high temperature range up to 200 °C
• Excellent low temperature impedance and ESR behaviour
• Charge and discharge proof, application with
0 ohm resistance allowed

Here are Vishay's Australian distributors/agents/sales offices:
http://www.vishay.com/capacitors/list/product-28354/sales?locs=Australia

- Franc Zabkar
 
C

Clifford Heath

Jan 1, 1970
0
Thanks all, the oven is working perfectly. Rockby had the
exact part (220uF 25V 125degC), and they were less than a
kilometre detour for my son this morning. WIN!

Clifford Heath.
 
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