On 11/12/2024 10:58 AM, Dan Langille via Nut-upsuser
wrote:> Hello,
>
> nut recently told me that the batteries need replacing in my Eaton
5PX2200RT (ups) and 5PXEBM48RT (external battery pack). According to my notes,
it has been just over 4 years since I installed them. Looking at on-line sales,
these seem to use batteries in a pre-packaged plastic shell. I don't recall
if that's what's in my units or not.
>
> Do you have any experience with replacing / filling such shells with 3rd
party batteries?
I have never had to replace batteries in an Eaton anything.
I hope the following is both correct and useful.
I have replaced a fair number (probably around a hundred) batteries in
other UPSes and devices (like a Fuji X-Ray machine that takes 16
12VDC at 22AH batteries). That's over 200VDC at a Significant current (the
batteries claim 12V, but they are charged to over 13V).
I like batteries from RaionGroup.com or batterywholesale.com.
There are some other companies out there that I will never buy from again.
I try to get high-rate batteries, and they are harder to find. As I
recall, one should avoid "deep discharge" batteries for UPSes. A deep
discharge battery is great for constant load stuff (like wheelchairs,
golf carts, etc) but UPSes need "shorter" bursts of lots of power.
I read the spec sheets and order the heaviest batteries I can find.
More lead means heavier batteries, and longer life.
I check each battery's initial voltage. I have a note that says I
expect at least 12.9V, but I haven't had a chance to verify this lately.
I check the spec'd net weight of the batteries with the actual weight of
each arriving battery.
Every battery I have received from the above 2 vendors has had a gross
weight clearly above the spec'd net weight of the battery. Yay.
Every battery I have received from at least one other vendor has had a
gross weight of at least 10% UNDER the spec'd net weight. I have
immediately called for an RMA of these, with varying degrees of success
in their return.
Oh, at least one vendor has offered both "regular" and "high
rate"
batteries, I ordered the more expensive "high rate" batteries, and
what
was delivered was "regular" batteries. When I asked about this, they
said something like "we don't get the high rate batteries anymore"
and
they had no answer for why they still showed and charged me for the
high-rate batteries when they knew they didn't actually have them. The
RMA process here was ... bad.
Anyway, when I have a set of replacement new batteries, I then:
- put each battery on a charger for several hours
- rotating thru the entire set at least twice
- then I take my bench supply with a (self-made) octopus cable
with individually-fused "hot" wires, and starting at .1V over the
average voltage, start adding batteries in parallel, waiting for the
current draw to reduce to a trickle. Once all of the batteries are
connected in parallel and drawing a trickle, I start bumping the
voltage by .1V until I get to either 13.5VDC (or the published
trickle charge voltage) and I let this sit there for a day.
When all the batteries are "balanced" in the parallel string, I then
install them into the battery tray(s) or directly into the unit.
Sometimes I will take the "old" batteries and run them thru the above
process to see if they will "recondition". Sometimes we will use
these
for lighting or other non-UPS tasks.
H