Irrigation Controller KwikDial KD4 KD6 KD8 KD12 Backup memory fault, No parts available from Irritrol - Torro design fault

[aus1]

The Irritrol KwikDial are great controlers with a great sales feature
that they backup your program should the power fail under 24 hours.
Never needs a battery so the sales pitch goes. Dam another power
outage - No programs kept !

Well all the External units in Australia are failing after a few years
and after no spare part availability of the circuit board, I decided
to open the unit up.

The designers had used Electric Double Layer capacitors Elna 0.33F
5.5 V Double coin type at PCB location C12 & C17.

There is a MAJOR design flaw as to why these are not lasting a
reasonable life.
Above super capacitors have their life extremely shortened if operated
less than 5°C or over 30°C and
HUMIDITY over 50%. (as Corrosion of leads and shorting of capacitor
cell corosion will occur).
http://www.elna.co.jp/en/capacitor/double_layer/attention/index.html
............................

WELL HELLO Irritrol - over 30°C & over 50% - sounds like a typical
Australia garden enviroment.
Not HAPPY! to shell out big buck again for another.

So In Australia, I'm repairing mine - although I know it will re-occur
- by replacing the super capacitors with imported USA stocked items
through Farnell, but for replacment you will need to have reasonable
desolding / resoldering skills as the printed circuit board is double
sided, and the replacement items legs may be a larger diameter & it's
a Horizonal version vs the OEM verticle, but the leg pich is nearly
correct verify + - as the capacitors are polarity sensitive.

Part Num. Quantity . Availability Line Price
Description Mfr Part # Mfr
Name
========= ========== ============ ==========
1340832 2 Refer Web 7.48 Supercapacitor;
Capacitance:0.33F; Serie EDLSD334H5R5C CORNELL DUBILIER

Hope this helps people out there so that they don't have to fork out
for a new unit that will fail anyway if they want there backup memory
to be retained <24 hours after the warranty runs out.

http://www.elna.co.jp/en/capacitor/double_layer/attention/index.html

Cheers !

[jmsm...@gmail.com]

Thanks for doing the legwork on this and explaining the problem in detail. This has helped me a lot.

[Bob F]

jmsm...@gmail.com wrote:
> Thanks for doing the legwork on this and explaining the problem in
> detail. This has helped me a lot.

Since you didn't quote anything of whatever you are talking about I don't have a
clue

[slo...@gmail.com]

This was excellent information