View Single Post
  #52   Report Post  
Posted to
Don Y[_3_] Don Y[_3_] is offline
external usenet poster
Posts: 2,879
Default bye-bye land line telephone

On 5/12/2016 4:56 PM, wrote:
On Thu, 12 May 2016 15:51:45 -0700, Don Y

On 5/12/2016 1:38 PM,
On Thu, 12 May 2016 12:56:05 -0700, Don Y

A battery will usually fix those "Bad" UPSs. They are not horribly
expensive online. That is why I have so many units around here. They
all came with bad batteries for free. I still have a few dead soldiers
back in my shop but I am UPSed out here. ;-)
There only seems to be 2 basic sizes with either 1 or 2 in each UPS

That's only for the smaller, consumer-ish units -- 12V 7.2AHr batteries.

I have a couple of these:
Which take the battery pack:

I have one just like that on my TV and sat box and you can replace
that "battery pack" with 2 batteries of equal AH that end up being
about $40 less if you shop around.

I don't care about the price. My point is that there are far
more variations in batteries -- battery sizes and numbers thereof.
I have a UPS that takes *one* battery. Some two. Others 4.
At one point, I had one that took *10* of the 12V 7.2AHr units
(it was the size of a dishwasher).

I have worked in places with a room full of group 27 deep cycle
batteries stacked 3 high in racks to power the UPS but this is not
what we are talking about.
APC uses 2 basic batteries in the half dozen or so units I have here.

As I said upthread:
"That's only for the smaller, consumer-ish units -- 12V 7.2AHr batteries."

Over the years:
originally used to power my "24/7/365" box. Discarded as it didn't have
much capacity (peak power as well as runtime) and was too tall to be of
practical use (I wanted to wedge it under a dresser in the bedroom). It
has *one* 7.2AHr battery in its belly.
also discarded for similar reasons (though it was lower profile and
I could slide it under one of my dressers -- not possible with the
previous unit)

I had a similar shape unit (but with a METAL skin) that also got
discarded because it took a *different* battery (shorter and fatter)
and I didn't want to have to buy two different styles of similar
capacity batteries (I buy batteries in bulk -- 10 at a time). Also,
it only had four outlets on the back and two of them were "pigtails".
This was OK when the 24/7 box and switch were the only "local
loads" but I now have a tablet PC and mouse charger plugged into
the same UPS (immediately below).

Yet another similar version (different shape):
is what currently powers the 24/7 box and the small 16port
switch adjacent. Again, one 12V 7.2Ahr battery underneath.

I have one of these powering the set of three monitors shared
by my two primary workstations:
I have another that powers my "personal stereo" and "PROM programmer"
(doesn't like to lose power when it is programming an EPROM!). They
take two of the 12V 7.2AHr batteries arranged side by side.

I have eight of these:
(or the 1200VA variants thereof) powering individual computers around
the house. They also serve as handy "extension cords" and "outlet
multipliers" -- allowing me to plug any specific peripherals that are
associated with that particular computer into the same device so
everything goes on/off with one switch. They take two of the 7.2AHr
batteries but stacked one atop each other.

[You can buy the "12V 7.2AHr" battery in different claimed capacities;
some as high as 9AHr. But, they're all the same physical size]
took a pass on a pair of these as they are really heavy (the bottom half
is "all battery") and too big to slide "under" anything. It has a *pair*
of these battery packs in it:
each "pack" is roughly the size of a car battery (though actually two
12V batteries glued together)

I currently have three of these to power my automation system:
though mine are the 1500VA size and equipped with network interfaces
(so the automation system can query the state of the UPS's). They
take *one* of the above battery packs.

I'm looking to replace these with something like the 3000VA version of:
mainly because it is powered by a 48V battery pack:
but entirely different size/shape batteries therein.

The 48V DC supply would allow me to directly power the PoE PSE without
requiring a separate 3000VA 48V power supply! I.e., the AC capabilities
of the UPS are largely ignored and it is treated as a big 48V battery.

But, a friend is suggesting addressing these needs separately; a tiny
100VA UPS to power the database server "PC" and a separate 48V battery
with charger -- noting that the charger need not RUSH to recharge
the battery pack after an outage (as is the problem with many UPS's).
If so, using flooded cells for the battery could give me a much lower
maintenance cost (lower the specific gravity)

In some units they just glue a couple together to create a "battery
pack" that they charge handsomely for, I suppose people who can't read
specs and do a little shopping appreciate the simplicity so APC does
it. There are plenty of customers who just throw the UPS away when the
battery is dead.

Exactly. Buying a UPS is almost silly, nowadays. If you can't find
someone EAGER to have you take theirs off their hands, you haven't

Unfortunately, the larger devices (2000VA+) tend to see use in data centers.
And, the folks there have budgets for battery replacements. So, discards
are harder to come by (and often rack mount forms)

These are industry standard parts and I want to get them at the best
available price. I certainly have not noticed that much difference
between the life of a APC sourced part and one I get from a battery
wholesaler. The wholesaler actually tends to have fresher ones.

I buy the "7.2AHr" batteries in lots of 10 or 12. This usually gives
me a 20% discount -- just for the quantity.

However, the larger UPS's need higher capacity batteries. So, this
means keeping two different types of batteries on hand. And, given
that batteries in THESE applications are intended NOT to be used/needed,
it's a huge bit of cash tied up "just in case".

So, I'm now looking for cheaper/lower capacity batteries with a goal
of just providing brownout protection and very short uptimes. The
individual computers talk to their specific UPS's so they can shut down
if the UPS tells them its failing. And, if I'm in the middle of something,
I can always save my work and come back to it at another time
(being able to "continue working" for long periods of time on any
of 8 or 10 computers "at random" is a hefty "support" requirement
for a UPS!). The *real* backup need is the automation system and
a single LONG TERM solution, there, can pay off handsomely -- WITH
the right UPS!