Memory backup battery

[Captdave]

Any one know where to get a memory backup battery for a Fagor 8025T. Is there a local purchase substitute such as from interstate batteries that anyone has used?

[skm]

The memory backup battery is just a 3.5v Lithium battery. However it is soldered into a box that has 2 resistors in it as well, hooked to the positive and negative ends of the battery circuit--I presume these are a mechanism to tell the charge left in the battery.

Get a 3.6 v Lithium battery from wherever (Radio shack has them, as does ebay, etc.)

Leave your control on so you don't lose parameters when changing the battery.

Remove the battery case by two screws, then you will see a circuit board with 1 battery and 2 resisters on it .

Use a utility knife or something with a similar wedge blade to get the spot welded ends off the factory battery without breaking them so you can solder the new battery back in place.

Position the knife, whack with mallet and they come off easy.

Solder new battery in place, observe polarity that is silk screened on the circuit board. Hint: solder won't stick to the plating on the ends of the battery, so use emery to remove the plating before soldering to the flat connectors.

As a check, use voltmeter on new battery to see you have full voltage, so you know your solder joints are good.

Reassemble black case so you don't short out anything.

Re-install battery.

Good for another couple of years. I've changed it 3 times in 14 years.

Oh, as insurance, take a half hour and back up your parameters by using a digital camera to take a picture of each screen of the parameters. There are so few parms that it doesn't take long, and it is indisputable proof of what the parms were on a given date. I find it better than downloading to a file because they don't get lost as individual downloaded files tend to, and you can see any individual parameter without going though a list. But that may just be me. But backup before you change the battery, so if a power failure happens while you are soldering, you are not posting here about how to recover the parameters.