Catastophic failure on ITV

In uk.tech.broadcast, on Sun, 1 Jun 2008 17:23:10, Zathras wrote:

My broadcasting experience is that we'd have had fewer bits of broken
kit and fewer outages if we hadn't had any UPSs at all!

Agreed!

At out new building, we don't have any - just two kinetic batteries
and a generator that comes up before the KB's spin down.

Outstanding idea.

--
Jim Crowther

"Zathras" wrote in message
...
snip

At out new building, we don't have any - just two kinetic batteries
and a generator that comes up before the KB's spin down.


I assume by "kinetic batteries" you mean 'motor-flywheel-generators',
if so, how is this implemented?

On Sun, 01 Jun 2008 17:23:10 +0100, Zathras wrote:

At out new building, we don't have any - just two kinetic batteries
and a generator that comes up before the KB's spin down.

Hopefully the generator comes up before the kinetics spin down...

--
Cheers
Dave.

Java Jive wrote:
Somehow, I can't show any surprise ...

snips long scary story

Our critical servers are all fitted with dual PSUs. The idea is that
one is fed from the UPS, and one straight from the mains. Lose the
mains, and the UPS kicks in. Lose the UPS, and they run straight from
the mains. (we're moving machine rooms soon, and as I now "own" some of
the servers, I'll check that they really are like that in their new home)

Repeat after me: "No Single Point Of Failure"

Andy

On 01/06/2008 23:02, Andy Champ wrote:

Our critical servers are all fitted with dual PSUs. The idea is that
one is fed from the UPS, and one straight from the mains. Lose the
mains, and the UPS kicks in. Lose the UPS, and they run straight from
the mains.

Early morning generator test occurs, you loose mains for a few seconds,
no problem UPS cuts in, generator starts, that extra server you added
recently increases the inrush current as half of your PSUs come back on
line at once, mains MCB trips, current drawn by the other half of your
PSUs is double normal, workload increases on the servers as people start
logging on for the day, servers draw that critical few extra amps, a
circuit breaker on the UPS reaches its limit and it trips, it goes dark
and quiet ...

On Sun, 01 Jun 2008 23:21:28 +0100, Andy Burns wrote:

Early morning generator test occurs, you loose mains for a few seconds,
no problem UPS cuts in, generator starts, that extra server you added
recently increases the inrush current as half of your PSUs come back on
line at once, mains MCB trips,

AWOOGA, AWOOGA, blooming great alarm goes off triggered by detecting
voltage across the MCB(s)...

--
Cheers
Dave.

"Richard Tobin" wrote in message
...
In article ,
:Jerry: wrote:

It seems from the DS posting made today, that the UPS let out a nice
fat spike.

There is some what of an irony in that, of all the devices to *cause*
an outage?! :~(

In 30 years of using computers, I have experienced innumerable
computer outages because of UPSes being installed, removed, serviced,
or exploding, and have never once had my computer stay up, or even
shut down in an orderly manner, when the mains was cut.



Heading up to the millenium I was responsible for maintaining a large test
facility and we were pulled in 4 weekends in a row to test the power backup
facilities. First weekend, after the power had been cut, the electricians
discovered that no one had thought to put diesel in the generator. Second
weekend the UPS went bang. Third weekend it was discovered that my test
facility was not actually connected into the power backup network. Fourth
weekend, power stayed up, but half the equipment went down because of spikes
on the voltage at switching.

The fifth weekend was the millenium itself, thankfully power backup was
never needed.

//Clive.

In article id, Jim
Crowther scribeth thus
In uk.tech.broadcast, on Sun, 1 Jun 2008 17:23:10, Zathras wrote:

My broadcasting experience is that we'd have had fewer bits of broken
kit and fewer outages if we hadn't had any UPSs at all!

Agreed!

At out new building, we don't have any - just two kinetic batteries
and a generator that comes up before the KB's spin down.

Outstanding idea.


Yep UPS's aren't the most reliable backup power. We directly float quite
a bit of Telecoms equipment off battery banks at either 24 or 48 volts,

Much more reliable that whopping it back up to 230 volts)..
--
Tony Sayer

On Sun, 01 Jun 2008 22:01:21 +0100 (BST), "Dave Liquorice"
wrote:

On Sun, 01 Jun 2008 17:23:10 +0100, Zathras wrote:

At out new building, we don't have any - just two kinetic batteries
and a generator that comes up before the KB's spin down.

Hopefully the generator comes up before the kinetics spin down...

It's regularly run, tested and maintained - if it's like our last one,
probably a twin engine unit. Totally reliable IME.

--
Z

On Sun, 1 Jun 2008 20:59:13 +0100, ":Jerry:"
wrote:


"Zathras" wrote in message
.. .
snip

At out new building, we don't have any - just two kinetic batteries
and a generator that comes up before the KB's spin down.


I assume by "kinetic batteries" you mean 'motor-flywheel-generators',
if so, how is this implemented?

Two contra-rotating units (fearlessly) located on the roof. They
supply energy instantly and for a longer time than the generator takes
to start and stabilise. I don't have any more detail of our
installation so for more than that, Google is the place to look - KBs
are amazing devices!

--
Z