UPS Making a "hissing" sound - need help

[Allister]

Hello everyone..

I have a Best Power Fortress UPS model LI660VA. In the last few
months, it started to make a hissing sound. The hissing sound sounds
like a tiny air leak or something. I took the cover off to see if I
could hear where it was coming from and it sounds like its coming from
the huge transformer in the rear of the UPS. So my questions are:

1) Do transformers make sounds like this?

2) If its the transformer, does that mean its going to die soon?

3) Is there anything that I can do to fix this problem?

I thought it was the batteries so I replaced those and it still does
the same thing. The batteries are in the front and the sound
continues even if I have the UPS on without any load and the batteries
disconnected.

Any help, tips, or pointers would be appreciated.

Thanks much,

-Jaime

 

[Chaos Master]

Eu năo acredito que Dr. Anton T. Squeegee escreveu:

It does have a multi-output DC/DC converter in it. 24VDC in and a
whole slew of logic-related voltages out, including bipolar 12.
Obviously got a switcher in there, but darned if I've ever been able to
figure out why it hisses.

I've heard that is from the DC/DC converter IC, when it gets hot.
So some hissing is perfectly normal IMHO.

--
by Chaos MasterŽ - MSN: wizard_of_Yendor@hotmail.com

"A Elbereth Gilthoniel, silivren penna miriel o menel aglar elenath!
Na-chaered palan-diriel o galadhremmin ennorath,
Fanuilos, le linnathon nef aear, si nef aearon!" - The Lord of the Rings

Linux User #327480 / GNU-Win32 / Cygwin

 

[Dr. Anton T. Squeegee]

In article <951fd107.0402221624.41e87297@posting.google.com>,
allistah@hotmail.com says...

<snippety>

1) Do transformers make sounds like this?

Don't know about transformers, but the control unit for our
access-control system (a Hirsch Electronics Digi-Trac M8) has made a
hissing noise when powered ever since I've owned it.

It does have a multi-output DC/DC converter in it. 24VDC in and a
whole slew of logic-related voltages out, including bipolar 12.
Obviously got a switcher in there, but darned if I've ever been able to
figure out why it hisses.


--
Dr. Anton T. Squeegee, Director, Dutch Surrealist Plumbing Institute.
(Known to some as Bruce Lane, ARS KC7GR,
kyrrin (a/t) bluefeathertech[d=o=t]calm -- www.bluefeathertech.com
"If Salvador Dali had owned a computer, would it have been equipped
with surreal ports?"

 

[James Sweet]

"Chaos Master" <chaos.master@brasnet.org> wrote in message
news:MPG.1aa3482856602b23989693@NEWS.INDIVIDUAL.NET...

Eu năo acredito que Dr. Anton T. Squeegee escreveu:


It does have a multi-output DC/DC converter in it. 24VDC in and a
whole slew of logic-related voltages out, including bipolar 12.
Obviously got a switcher in there, but darned if I've ever been able to
figure out why it hisses.

I've heard that is from the DC/DC converter IC, when it gets hot.
So some hissing is perfectly normal IMHO.

Probably not from the IC, I bet it's the windings or core of the inductor
resonating, that's usually the cause of transformer hum, or hiss in the case
of high frequency magnetics.

 

[Allister]

So you guys think that it's ok to run this UPS with this hissing
sound? I'm not gunna have to worry about a cap blowing up or
something bad happening while I'm at work and the wife is at home with
it? heh

Thanks for the info guys,

-Jaime

"James Sweet" <jamessweet@hotmail.com> wrote in message news:<Wff_b.245223$U%5.1648933@attbi_s03>...

"Chaos Master" <chaos.master@brasnet.org> wrote in message
news:MPG.1aa3482856602b23989693@NEWS.INDIVIDUAL.NET...
Eu năo acredito que Dr. Anton T. Squeegee escreveu:


It does have a multi-output DC/DC converter in it. 24VDC in and a
whole slew of logic-related voltages out, including bipolar 12.
Obviously got a switcher in there, but darned if I've ever been able to
figure out why it hisses.

I've heard that is from the DC/DC converter IC, when it gets hot.
So some hissing is perfectly normal IMHO.




Probably not from the IC, I bet it's the windings or core of the inductor
resonating, that's usually the cause of transformer hum, or hiss in the case
of high frequency magnetics.

 

[James Sweet]

"Allister" <allistah@hotmail.com> wrote in message
news:951fd107.0402231011.b2fd3d9@posting.google.com...

So you guys think that it's ok to run this UPS with this hissing
sound? I'm not gunna have to worry about a cap blowing up or
something bad happening while I'm at work and the wife is at home with
it? heh

Thanks for the info guys,

-Jaime

I wouldn't worry about it as long as there's no weird smells.