Battery or transformer

D

Don Phillipson

My UPS, Belkin 375, was guaranteed for 3 years -- and just failed after 42
months. The component obviously running too hot was not the battery
(as expected) but the transformer. So I am undecided whether to
replace the battery; I would not attempt to replace the transformer.
1. Is it normal for a (lead-acid) battery at the end of its life to cause
UPS
overheating and auto-off? (It is hard to imagine the transformer
degrading or overheating by itself.)
2. Are there nowadays non-lead batteries (to replace a Ritar RT1240)
that might work better?
 
J

John Doe

Don Phillipson said:
My UPS, Belkin 375, was guaranteed for 3 years -- and just
failed after 42 months. The component obviously running too
hot was not the battery (as expected) but the transformer. So I
am undecided whether to replace the battery; I would not attempt
to replace the transformer.

Your UPS failed. You think the transformer was running too hot. So
you're going to replace the battery and not the transformer.

WTF?
That's a rhetorical question.

Anybody who thinks that a UPS is useful might want to consider a
voltage regulator (a.k.a. line conditioner). The vast majority of
PC users don't need a UPS, it just seems cool to run the computer
on battery power for a while.
--
 
P

Paul

Don said:
My UPS, Belkin 375, was guaranteed for 3 years -- and just failed after 42
months. The component obviously running too hot was not the battery
(as expected) but the transformer. So I am undecided whether to
replace the battery; I would not attempt to replace the transformer.
1. Is it normal for a (lead-acid) battery at the end of its life to cause
UPS
overheating and auto-off? (It is hard to imagine the transformer
degrading or overheating by itself.)
2. Are there nowadays non-lead batteries (to replace a Ritar RT1240)
that might work better?

That's possibly a Chinese battery.

http://www.ritarpower.com/About.aspx?id=11

Have you talked to Belkin yet ? What arrangements
will they make for transport ? Do you have to
ship it back for warranty service ? Or do they
offer authorized dealers near you ?

Transformers can get hot on their very own. I
have a transformer here (around 12V 4A), which
runs way too hot after sitting *idle* for an
hour plugged in. It's obvious some kind of
lamination failure has occurred, because it
didn't used to get hot like that. So the
transformer itself can fail, if eddy currents
flow through the laminations. Laminations are
coated, to stop that.

http://en.wikipedia.org/wiki/Transformer

"Later designs constructed the core by stacking
layers of thin steel laminations, a principle
that has remained in use. Each lamination is
insulated from its neighbors by a thin non-conducting
layer of insulation."

"The effect of laminations is to confine eddy
currents to highly elliptical paths that enclose
little flux, and so reduce their magnitude.
Thinner laminations reduce losses"

If the laminations short together, the loss
goes up, and the transformer gets hot. My
transformer still seems to product the
correct output (so it's not a shorted winding),
but at zero current flow, it still gets hot. And
that could be an eddy current problem (caused
by rusting). I can run the transformer for about
an hour, before I have to turn it off due to the
surface temperature reached.

I think I'd let Belkin sort this out.

Paul
 
D

Don Phillipson

The vast majority of
PC users don't need a UPS, it just seems cool to run the computer
on battery power for a while.

Where the electricity supply is at all likely to fail while the PC
is running (5 to 10 times a year at this rural address) a UPS
is well worth the expense. It lets users shut down without
sudden loss of data. (I have used them since about 1993.
A UPS was essetial for DR-DOS and Win95.)

Respondent Paul described clearly how transformers
can fail with age: helpful information.
 
D

david

Have you talked to Belkin yet ? What arrangements will they make for
transport ? Do you have to ship it back for warranty service ?

His warranty expired 6 months ago.
 
L

larry moe 'n curly

Don said:
My UPS, Belkin 375, was guaranteed for 3 years -- and just failed after 42
months. The component obviously running too hot was not the battery
(as expected) but the transformer. So I am undecided whether to
replace the battery; I would not attempt to replace the transformer.

1. Is it normal for a (lead-acid) battery at the end of its life to cause
UPS
overheating and auto-off? (It is hard to imagine the transformer
degrading or overheating by itself.)

If you paid for the Belkin with a Visa or American Express credit
card, their warranty extension program may help you. They double
factory warranties by up to a year. With Visa the original warranty
can be up to 3 years, with Amex, up to 5 years. Both companies handle
claims very well. OTOH Mastercard's protection applies only to
original warranties of 12 months or less, and their service seems to
be really bad (Pay $100 for a repair estimate on a $50 product, and MC
won't reimburse you for the estimate). BTW in the last couple of
years, Discover card has added protection for warranties of up to 3
years, but apparently not all customer accounts have this.

Did the transformer really fail? I don't have an UPS, just some
backup supplies that switch over to battery only during blackouts, yet
their transformers run pretty hot, even when they're doing nothing but
charging their batteries. Generally when a big transformer fails, a
thermal fuse tucked into the windings melts open, and your ohm meter
will read infinity when you measure the primary side. If it shows
continuity there, can you run the transformer safely, that is, unplug
it from the UPS circuitry (to prevent high voltage from being
generated by that circuitry) and measure its output directly (AC cord
plugged into an outlet protected by a ground fault circuit interrupter
and a friend standing nearby in case you get shocked) ?
2. Are there nowadays non-lead batteries (to replace a Ritar RT1240)
that might work better?

You'd have to modify the charging circuit, especially for a lithium
battery, which requires really accurate measurement of the voltage for
proper charging and to avoid a serious fire or explosion risk if
there's any overcharging. It should be easier to accommodate nicad or
NiMH charging, but the charging circuit will probably still have to be
modified, and those batteries are a lot, lot bigger for the same
energy capacity. You'll probably need real D cells (many rechargeable
D cells are actually C or AA cells) rated for at least 5 amp*hours.

I've found that the lead-acid batteries of backup supplies don't last
much more than about 3 years, and even if they pass the backup's built-
in self test they can be really weak and not be able to power a
computer for more than 30 seconds. On Belkins the test can be
triggered manually by pressing the power button for about 1/2 to 1
second, and it loads down 3-4 amp*hour batteries by about 150-300 mA
for about 15 seconds.

Is your Belkin a model F6H-375-USB? I have a couple of them, and
they're completely different inside from one another, except for the
battery. The older one was made by Delta, and has a transformer the
size of a baseball or softball, while the newer one is by Central Lion
and uses a tiny transformer (high frequency?). The Delta once failed,
but I couldn't find anything wrong with it (no shorted diodes or
transistors, capacitor ESRs were OK), and resoldering the board or
changing the battery didn't help, but after a couple of years in
storage, it works again. Neither backup has the best surge
protection, and there's practically no line filter to prevent a laser
printer plugged into a nearby outlet from crashing the computer
(unlike APC backups).

If you live in the vicinity of a Fry's, they sometimes advertise a
550VA APC for $30, after rebate, and currently they have a 675VA
Cyberpower for $50, AR.
 
L

Loren Pechtel

Your UPS failed. You think the transformer was running too hot. So
you're going to replace the battery and not the transformer.

WTF?
That's a rhetorical question.

Anybody who thinks that a UPS is useful might want to consider a
voltage regulator (a.k.a. line conditioner). The vast majority of
PC users don't need a UPS, it just seems cool to run the computer
on battery power for a while.

We use UPSes because the power sometimes blinks. Generally it's only
a fraction of a second but that's enough to cause a reboot.
 
L

Loren Pechtel

My UPS, Belkin 375, was guaranteed for 3 years -- and just failed after 42
months. The component obviously running too hot was not the battery
(as expected) but the transformer. So I am undecided whether to
replace the battery; I would not attempt to replace the transformer.
1. Is it normal for a (lead-acid) battery at the end of its life to cause
UPS
overheating and auto-off? (It is hard to imagine the transformer
degrading or overheating by itself.)
2. Are there nowadays non-lead batteries (to replace a Ritar RT1240)
that might work better?

I've noted that failed UPS lead-acid batteries tend to get hot. I
don't know why the transformer would, though.
 
D

Davej

L

Lynn McGuire

Your UPS failed. You think the transformer was running too hot. So
you're going to replace the battery and not the transformer.

WTF?
That's a rhetorical question.

Anybody who thinks that a UPS is useful might want to consider a
voltage regulator (a.k.a. line conditioner). The vast majority of
PC users don't need a UPS, it just seems cool to run the computer
on battery power for a while.

We get power blinks weekly at our office in Sugar Land,
Texas. I call it "the UPS test".

Lynn
 

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