HP 3468A HP-IL Digital Multimeter

[rprosperi]

(05-25-2014 02:45 AM)Paul Berger (Canada) Wrote:  The original battery may be hard to find but in the forum that Katie provided the link for there are a few examples of cells that people successfully used to replace the memory backup battery, and the process they used to replace it while preserving the calibration data. There is even one example of what not to do.

According to the service guide the original battery was rated for 3V at 0.95Ah, the 3.6V Primary lithium-thionyl chloride battery will also work. I just ordered a couple Saft LS14250 cells to replace the batteries in my 3468A and 3421A. This battery is rated at 3.6V 1.2Ah you will see in the forum that Katie linked that other have used batteries that have an even high Ah rating than the ones I ordered. In theory a battery with a higher Ah ratinfg should last longer, however you do not want to wait until the end of the batteries life to replace it as they go from full to completely dead in the matter of hours.

Thanks for the info Paul. What is the best way to tell if the battery is nearing EOL? With the near-90 degree drop-off curve (all lithiums are steep, but I've never seen one quite so 'cliff-like') it doesn't appear any measurement would help; perhaps it's best to just do it, assuming at this age it's likely close to the end?