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Old 02-12-2012, 08:22 AM   #101 (permalink)
IamIan
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Quote:
Originally Posted by eq1 View Post
any reason to discharge/charge manually versus auto?
Not speaking for him ... I'll just say.

Nothing is 100% ... The control logic for the Super Brain 989 is not 100% reliable either.

I have occasionally had it stop charging early long before a battery is actually charged ... although that only happens rarely , it does exist ... this can be easily noticed and corrected if working manually for each step... from my experience I'd say less than 10% of the charge cycles will have this issue ... and it does no harm to the battery, it is just not a full charge cycle.

Another rare issue I've had with the less than 100% reliability of the Super Brain 989 is on discharge ... on very rare occasions when discharging multiple cells in series it can fail to quickly detect when a single cell reaches 0V and goes into voltage reversal ... This is even more rare, I'd say less than 1% chance ... but it can potentially do damage to the cell it puts into voltage reversal... attached at the bottom is a graph of one such event I caught while logging the voltage with a different device ... the one cell reversal is clearly apparent... and the graph ends where the Super Brain 989 ended the discharge ... it was a NiMH battery pack of 10 series D cells that had been sitting for a while and one of them was out of SoC Balance with the others.

The last issue I have with the less than 100% reliability of the Super Brain 989 is on power supply mode ... don't ever depend on a Super Brain 989 in power supply mode to sustain regulated voltage or current ... although this does not effect battery cycling.

But manual supervision of each step adds a lot of time to a project that already will eat many many hours as is without doing so... and no device is 100% reliable ... that's just how it is ... of course there are other competing devices ... but there is no published 3rd party reliability tests of them that I know of in order to get a good properly quantified evaluation to know if item B is any better or worse than item A.

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