[Nut-upsuser] Eaton 5PX 3rd party batteries

[Dan Langille]

On Fri, Nov 29, 2024, at 3:35 PM, Dan Langille via Nut-upsuser wrote:
> On Wed, Nov 27, 2024, at 10:56 AM, Greg Troxel via Nut-upsuser wrote:
>> Dan Langille via Nut-upsuser <nut-upsuser at alioth-lists.debian.net>
>> writes:
>>
>>>> On the website, they say 5.73 pounds (5 lbs 11.6 oz).
>>>>
>>>> Two of the batteries were 5 lbs 11 oz.  The rest were all 10, 9, or 8 oz.
>>>>
>>>> See my bar chart at https://bsd.network/web/@dvl/113555334752647203
>>>
>>> The batteries are all within 3% of the expected weight. Seems good enough for me.
>>>
>>> I gave some thought as to how to distribute those 16x batteries within the UPS (4x) and the external battery unit (12x).
>>>
>>> In the following, I'm omitting the 5lb part of the weight and mention only the ounces.
>>>
>>> Not that I think it will make much difference, but I'll put all the four equal batteries into the UPS (4x 10oz batteries).
>>>
>>> That will leave the following for the external pack:
>>> '
>>> * 2 x 11
>>> * 1 x 10
>>> * 7 x 9 
>>> * 2 x 8
>>>
>>> The other choice I'd make: put 2 x 11 and 2 x 10 in the UPS, leaving the external battery
>>> unit with:
>>>
>>> * 3 x 10
>>> * 7 x 9 
>>> * 2 x 8
>>>
>>> I don't know enough to know if this matters and I expect I'm merely overthinking this.
>>
>> You are definitely overthinking it :-)  Perhaps you've previously been
>> diagnosed as a nerd!
>
> Possibly. I also have a rain-barrel project underway, and I know I'm 
> overthinking that one too.
>
>> But, I would either put the 4 strongest in the UPS, or the 4 weakest,
>> making the external pack better, since it is more important.
>>
>> I would suggest that you get a West Mountain CBA, if you want to
>> continue to overthink this.  We are assuming that more lead is more
>> capacity, but there are also weak cells, not clearly related to missing
>> lead.   What really matters, IMHO, is how many Ah one can pull out of
>> the battery, and measuring that directly seems more direct.
>
> I understand, and no, I'm done with this stage of the process. I don't want
> to geek out any further.
>
> So far, every battery has been charged. Each took about 30 minutes. When charged
> they measured about 13.3-13.5V.  The first batteries I charged are now at about
> 12.9-13.1V - one was 12.8V
>
> They're sitting in a room that is about 63F.
>
> My next step is to pull the main battery from the 5PX and replace those 
> units. However,
> it's 3:30 PM and I'd rather start such a project earlier in the day 
> should
> thing take longer than expected. 
>
> One server has a drive ready to be replaced and two drives are to be
> relocated from the drive bays at the front to PCI slots in the rear of 
> the server.
> That process is waiting on parts. I was going to wait for those parts 
> and do the drives
> and batteries at the same time. I changed my mind; I'm not going to 
> wait. Plus,
> the batteries may be a big enough job by themselves. I am sure the 
> Eaton 5PX legacy
> is not a hot-swappable unit. I'll power everything down.
>
>> Thanks for posting about your journey; it has been illuminating to me.
>
> I'm glad it helps. I write mostly for selfish reasons and encourage 
> others to do so
> too. It helps to know what you did should something go wrong and/or you 
> want
> to repeat the procedure later. If you make your writing public it will 
> also
> help others and I'm thankful of that.

The batteries were replace earlier today. Details with photos in the this blog post:

https://dan.langille.org/2024/11/30/replacing-batteries-eaton-5px-5px2200rt-5pxebm48rt/

Some tricky bits, especially a metal nut very close to the fuses... A slice of cardboard
helped me through that part.

BONUS: I ordered four more batteries than I needed (12). This means the UPS in the office,
which I'm sure will start screaming for new batteries soon, has a supply already on hand.

-- 
  Dan Langille
  dan at langille.org