I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

Scott wrote:

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption

a UPS generally does consume a background amount of power, how else do
they cook their batteries with heat? The amount will vary depending
whether it's an offline, online, or line interactive type.

On Sun, 25 Aug 2019 14:57:31 +0100, Andy Burns
wrote:

Scott wrote:

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption

a UPS generally does consume a background amount of power, how else do
they cook their batteries with heat? The amount will vary depending
whether it's an offline, online, or line interactive type.

Thank you. This is what I suspected. Could you quantify at all?
Would a domestic UPS use more power than, say, a TV on stand-by?

On Sun, 25 Aug 2019 14:57:31 +0100, Andy Burns wrote:

a UPS generally does consume a background amount of power, how else do
they cook their batteries with heat?

My APC Smart UPS 700 doesn't any more. The Friday cut and the much
longer one the follwoing Mondy proved that the mods I have made to it
have stopped it killing its batteries.

It used to kill a set of batteries in around 4 years. After the last
lot almost went into literal meltdown (the smell is what alerted me)
I made some mods before putting a new set of batteries in. That was
March 2014, so without mods they would be dead or next to useless by
now.

The UPS kept everything it's supposed to up for the 20 odd minutes of
the Friday outage. On the Monday it ran for the expected time before
shuting down with low battery. The recharge time before switching
back on was as expected as well.

The mods where reducing the charge voltage, and fitting a temperature
controlled fan and possibly some tweaks to firmware settings. A
search back in here may well find more details.

The amount will vary depending whether it's an offline, online, or line
interactive type.

At a rough guess I'd say mine takes 15 W +/- 5 W.

--
Cheers
Dave.

Dave Liquorice wrote:

Andy Burns wrote:

a UPS generally does consume a background amount of power, how else do
they cook their batteries with heat?

My APC Smart UPS 700 doesn't any more.

I did a minor adjustment with the "hidden" serial command, can't
remember the exact float voltage I set 27.something, whatever the Yuasa
spec said, even though they're not Yuasa batteries in it.

Mine has 4 of the 18Ah batteries and now the electronics lump at the top
of the case still gets warm (it's often running in buck mode) noticeably
above ambient, but the battery lump at the bottom of the case is nowhere
near as warm.


The Friday cut and the much
longer one the follwoing Mondy proved that the mods I have made to it
have stopped it killing its batteries.

It used to kill a set of batteries in around 4 years.

Mine were last changed july 2015, I no longer do the weekly test, but
they worked last time I checked.

After the last
lot almost went into literal meltdown

Only seen that when someone had fitted "alarm" batteries, rather than
"NP" batteries.

At a rough guess I'd say mine takes 15 W +/- 5 W.

I think mine was about 30W for a SU2200 plus the same again for an 8 way
smart PDU, but then I realised I didn't exactly need to remotely
power-cycle individual kit, so I no longer use that.

Andy Burns wrote:

I did a minor adjustment with the "hidden" serial command, can't
remember the exact float voltage I set 27.something, whatever the Yuasa
spec said

54.05 volts.

On Sun, 25 Aug 2019 21:01:19 +0100, Andy Burns wrote:

My APC Smart UPS 700 doesn't any more.

I did a minor adjustment with the "hidden" serial command,

Hardware mod on mine. If there was a firmware tweak it either didn't
do what it said it would or had undesirable knock on effects. I have
vague memories of the latter.

Mine has 4 of the 18Ah batteries and now the electronics lump at the top
of the case still gets warm

Once I have a bit a spare cash I might get a set of batteries for the
SU2200 I have sitting doing nothing...

(it's often running in buck mode)

It was getting the UPS that alerted me to the fact our supply voltage
was high. Plugged it it, straight into voltage reduction mode,
measure supply close to 250 V, rang DNO, engineer at door inside two
hours, they measured agreed it was high, came back within a couple of
days and andjusted the tapping on "our" pole transfomer. Voltage now
240 and, at that time, the consumption of incandescent light bulbs
noticably dropped...

--
Cheers
Dave.

On Mon, 26 Aug 2019 10:10:53 +0100 (BST), "Dave Liquorice"
wrote:

On Sun, 25 Aug 2019 21:01:19 +0100, Andy Burns wrote:

My APC Smart UPS 700 doesn't any more.

I did a minor adjustment with the "hidden" serial command,

Hardware mod on mine. If there was a firmware tweak it either didn't
do what it said it would or had undesirable knock on effects. I have
vague memories of the latter.

We have several (mainly APC) UPS's here and my normal test to their
efficiency (outside plugging them in my power meter socket thing) is
how warm they sit when idle. Most of them are 'just warm' but I would
be interested to learn if there was a specific procedure to lower the
risk of overcharging the battery (assuming such hasn't already been
applied as they are all s/h).

We have one 'Back-UPS CS 350 (that is on 'Her' PC) and several
'Back-UPS 650's'. Ironically my Windows Home Server has sat there ~10
years but not on a UPS and has survived several power outages over
that time with no issue?

Mine has 4 of the 18Ah batteries and now the electronics lump at the top
of the case still gets warm

Once I have a bit a spare cash I might get a set of batteries for the
SU2200 I have sitting doing nothing...

I also have a 1000 and 1500 VA APC 'Smart UPS's' but like you I'm
waiting for some spare cash (or reason) to get some batteries for
them. ;-)

Cheers, T i m

Scott wrote:

I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

Yes, but only journalists who can't do sums, and battery manufacturers,
see a major role for batteries in solving this problem.




I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

It always consumes some, for the electronics and for charging the
battery. And the best kind, with an inverter always online, lose power
in the inverter.



As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?
Yes. Depending on the filesystem and luck it could damage it even if
it is not actively doing anything.

--

Roger Hayter

On Sunday, 25 August 2019 14:50:37 UTC+1, Scott wrote:

I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

The battery charger is not 100% efficient. Once fully charged the battery is often then overcharged continually. Turning 12v or 24v back to 110/230v is also not entirely efficient.


As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

For sure, your filesystem can be totally borked - though it usually survives unharmed. NTFS has been much hyped as more robust in this respect, but it's only a limited subset of data that gets duplicated, so it's almost as vulnerable as FAT32.

Roger summed it up very well with
"Yes, but only journalists who can't do sums, and battery manufacturers,
see a major role for batteries in solving this problem."

Even if UPSes were 100% efficient, they would still not be practical for grid backup. The costs, pollution, energy consumption in manufacture and vast demand for lead would be problematic.


NT

On Sun, 25 Aug 2019 08:55:48 -0700 (PDT), wrote:

Even if UPSes were 100% efficient, they would still not be practical for grid backup.

That'll be why 450 MW (ish) of battery was called upon to help keep
the grid up the other Friday. Mind you it's not been stated for how
long said "battery" could supply that power...

The costs, pollution, energy consumption in manufacture and vast demand
for lead would be problematic.

More likely to be lithium than lead. But isn't there some other weird
and wonderful battery technology about using molten sulphur or
something?

--
Cheers
Dave.

On Sunday, 25 August 2019 19:57:13 UTC+1, Dave Liquorice wrote:
On Sun, 25 Aug 2019 08:55:48 -0700 (PDT), tabbypurr wrote:

Even if UPSes were 100% efficient, they would still not be practical for grid backup.

That'll be why 450 MW (ish) of battery was called upon to help keep
the grid up the other Friday. Mind you it's not been stated for how
long said "battery" could supply that power...

The costs, pollution, energy consumption in manufacture and vast demand
for lead would be problematic.

More likely to be lithium than lead. But isn't there some other weird
and wonderful battery technology about using molten sulphur or
something?

Half a gigawatt is a long way from running the grid


NT

wrote in message
...
On Sunday, 25 August 2019 19:57:13 UTC+1, Dave Liquorice wrote:
On Sun, 25 Aug 2019 08:55:48 -0700 (PDT), tabbypurr wrote:

Even if UPSes were 100% efficient, they would still not be practical
for grid backup.

That'll be why 450 MW (ish) of battery was called upon to help keep
the grid up the other Friday. Mind you it's not been stated for how
long said "battery" could supply that power...

The costs, pollution, energy consumption in manufacture and vast demand
for lead would be problematic.

More likely to be lithium than lead. But isn't there some other weird
and wonderful battery technology about using molten sulphur or
something?

Half a gigawatt is a long way from running the grid

It isnt meant to run the entire grid.

On Mon, 26 Aug 2019 14:33:45 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


It isnt meant to run the entire grid.

Oh, ****! And this little thread was Rodent-free, so far! tsk

--
Richard addressing Rot Speed:
"**** you're thick/pathetic excuse for a troll."
MID:

On Sun, 25 Aug 2019 15:22:34 -0700 (PDT), wrote:

The costs, pollution, energy consumption in manufacture and vast
demand for lead would be problematic.

More likely to be lithium than lead. But isn't there some other
weird
and wonderful battery technology about using molten sulphur or
something?

Half a gigawatt is a long way from running the grid

True but it might be the half a gigawatt of dispatchable that keeps
the frequency up just enough...

--
Cheers
Dave.

In message l.net,
Dave Liquorice writes
On Sun, 25 Aug 2019 15:22:34 -0700 (PDT), wrote:

The costs, pollution, energy consumption in manufacture and vast
demand for lead would be problematic.

More likely to be lithium than lead. But isn't there some other
weird
and wonderful battery technology about using molten sulphur or
something?

Half a gigawatt is a long way from running the grid

True but it might be the half a gigawatt of dispatchable that keeps
the frequency up just enough...

Not seen one lately, but there have been a raft of adverts looking for
roadside space next to high voltage supplies.

Flavour of intent here..
https://www.ukpowernetworks.co.uk/in...uments/SNS1.2_
SDRC_9.1_Design_and_Planning_Considerations_Report _v2.0.pdf

--
Tim Lamb

On 26/08/2019 10:18, Dave Liquorice wrote:
On Sun, 25 Aug 2019 15:22:34 -0700 (PDT), wrote:

The costs, pollution, energy consumption in manufacture and vast
demand for lead would be problematic.

More likely to be lithium than lead. But isn't there some other
weird
and wonderful battery technology about using molten sulphur or
something?

Half a gigawatt is a long way from running the grid

True but it might be the half a gigawatt of dispatchable that keeps
the frequency up just enough...


2GW probably would have, but we don't know for how long the batteries
could supply it for.

This is going o be the next "con".. FITs for installing batteries.
It effectively government borrowing but it doesn't go on the books and
the consumers pay for it in the end.

harry will have one of them as soon as he can make enough cash from it.

wrote in message
...
On Sunday, 25 August 2019 14:50:37 UTC+1, Scott wrote:

I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

The battery charger is not 100% efficient. Once fully charged the battery
is often then overcharged continually. Turning 12v or 24v back to 110/230v
is also not entirely efficient.


As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

For sure, your filesystem can be totally borked - though it
usually survives unharmed. NTFS has been much hyped as
more robust in this respect, but it's only a limited subset of
data that gets duplicated, so it's almost as vulnerable as FAT32.

Its easy to defrag so no mains failure will bork anything.

Roger summed it up very well with
"Yes, but only journalists who can't do sums, and battery manufacturers,
see a major role for batteries in solving this problem."

Even if UPSes were 100% efficient, they would still not be practical for
grid backup.

But they can be viable to help with when a wind farm drops
off the grid for whatever reason and provide a replacement
for that short term loss from the grid until it reconnects.

The costs, pollution, energy consumption in manufacture
and vast demand for lead would be problematic.

The dont supply the entire feed to the grid.

On Mon, 26 Aug 2019 12:13:22 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


Its easy to defrag so no mains failure will bork anything.

YOU need your brain defragged (in a loony bin) occasionally, senile asshole
troll!

--
Marland answering senile Rodent's statement, "I don't leak":
"That¢s because so much **** and ****e emanates from your gob that there is
nothing left to exit normally, your arsehole has clammed shut through disuse
and the end of prick is only clear because you are such a ******."
Message-ID:

On Sunday, 25 August 2019 14:50:37 UTC+1, Scott wrote:
I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

Batteries have internal resistance.
Which varies according to type of battery, age and state of charge.
Ergo Ohms law applies. W=I2R
Both charging and discharging.

On Sunday, 25 August 2019 14:50:37 UTC+1, Scott wrote:
I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

Don't fret. Buy yourself a laptop.

On 25/08/2019 14:50, Scott wrote:
I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?


https://delta.ecoflow.com/?fbclid=Iw...R3xD5Wny8e5QuA

wonder how much that will cost.....?

On 25/08/2019 14:50, Scott wrote:

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?


Yes but so could a hardware fault or a software crash.
This is why you need a good data backup system.
It will allow you to recover from a corrupted disk caused by anything.

Also UPS systems fail too.

In article ,
dennis@home wrote:
On 25/08/2019 14:50, Scott wrote:

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?


Yes but so could a hardware fault or a software crash.
This is why you need a good data backup system.
It will allow you to recover from a corrupted disk caused by anything.

Also UPS systems fail too.

in the mid 1990s I was working in a building which sat astride the Great
Weatern Railway and was a terminus for one of the London Underground lines.
One weekend, We were warned that there would be work on our electrical
supply so all computer equipment should be turned off. OUr IT people said
"don't worry about that we have UPS". On the Monday morning it was found
that every UPS had blown up because of over voltage. It was well after 2pm
that my computer came back to life.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

On 25/08/2019 19:34, dennis@home wrote:
On 25/08/2019 14:50, Scott wrote:

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?


Yes but so could a hardware fault or a software crash.
This is why you need a good data backup system.
It will allow you to recover from a corrupted disk caused by anything.

Also UPS systems fail too.

Decent servers have two power supplies.

Wise IT people connect one to the raw mains, and the other to the UPS,
so if either fails it keeps going.

Andy

On 25/08/2019 21:47, Vir Campestris wrote:
On 25/08/2019 19:34, dennis@home wrote:
On 25/08/2019 14:50, Scott wrote:

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?


Yes but so could a hardware fault or a software crash.
This is why you need a good data backup system.
It will allow you to recover from a corrupted disk caused by anything.

Also UPS systems fail too.

Decent servers have two power supplies.

Wise IT people connect one to the raw mains, and the other to the UPS,
so if either fails it keeps going.

Andy

Decent systems have more than one server and more than one UPS.

"Scott" wrote in message
...
I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

Depends on the type of UPS. The best of them charge the batteries all
the time and use the batteries to power what it is powering, so all that
happens on a mains failure is the batteries stop being charged. Those
clearly do waste some power all the time. The other sort that switch over
on a mains failure only waste power when replacing the self discharge.

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

Not when defragging. It can happen when flashing the bios.

With updates, it depends on whether you have a full backup etc.

On Mon, 26 Aug 2019 11:54:27 +1000, jeikppkywk, better known as cantankerous
trolling senile geezer Rodent Speed, wrote:

With updates, it depends on whether you have a full backup etc.

YOU need your medication updated, senile asshole! BTW, have you tried these
pills already:
https://thetravellingtiles.files.wor...b6f9820001.jpg

--
about senile Rot Speed:
"This is like having a conversation with someone with brain damage."
MID:

Yes sudden power cuts do screw up computers. It really depends what is going
on at the time. Many now use laptops for this reason of course, it has its
own built in ups.

Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Scott" wrote in message
...
I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

On Sun, 25 Aug 2019 14:50:32 +0100, Scott
wrote:

snip

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

Possibly, depending on how well it could recover automatically from
such etc, but depending on how the power is cut / re-connected, might
damage the electronics themselves.

Therefore, having a UPS between the supply and your electronics, may
act as a buffer / filter or the UPS could act as a sacrificial link.

I looked after a small office as a favour for a friend (because I
enjoyed / missed it) and I covered his PC's and servers with a
spattering of UPS's and the APCUPSD utility.

I need to look into that (and NUT?) to cover several boxes (RPi / PC's
running OMV NAS software) and possibly the Synology box, as only one
can be physically plugged into the UPS at a time?

Cheers, T i m

T i m wrote:

On Sun, 25 Aug 2019 14:50:32 +0100, Scott
wrote:

snip

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

Possibly, depending on how well it could recover automatically from
such etc, but depending on how the power is cut / re-connected, might
damage the electronics themselves.

Therefore, having a UPS between the supply and your electronics, may
act as a buffer / filter or the UPS could act as a sacrificial link.

I looked after a small office as a favour for a friend (because I
enjoyed / missed it) and I covered his PC's and servers with a
spattering of UPS's and the APCUPSD utility.

I need to look into that (and NUT?) to cover several boxes (RPi / PC's
running OMV NAS software) and possibly the Synology box, as only one
can be physically plugged into the UPS at a time?

Cheers, T i m

I think anything that can run apcupsd can be networked easily to the box
controlling the UPS. Remakably painless. It's only worth using NUT
(which can allegedly follow an apcupsd server) if there's something like
a NAS you can't install apcupsd on. NUT is less painless.

--

Roger Hayter

On Mon, 26 Aug 2019 13:25:32 +0100, (Roger Hayter)
wrote:

snip
I need to look into that (and NUT?) to cover several boxes (RPi / PC's
running OMV NAS software) and possibly the Synology box, as only one
can be physically plugged into the UPS at a time?


I think anything that can run apcupsd can be networked easily to the box
controlling the UPS. Remakably painless. It's only worth using NUT
(which can allegedly follow an apcupsd server) if there's something like
a NAS you can't install apcupsd on. NUT is less painless.

Thanks for that Roger.

I have seen NUT mentioned on the various bits of hard/software but
never tried to use it.

I need to check what both Synology and OMV will support and as you
say, if both will follow an APCUPSD server, that could answer my needs
in any case (as long as all my switches in between are also UPS
protected). ;-)

Cheers, T i m

On Monday, 26 August 2019 13:25:36 UTC+1, Roger Hayter wrote:

I think anything that can run apcupsd can be networked easily to the box
controlling the UPS. Remakably painless. It's only worth using NUT
(which can allegedly follow an apcupsd server) if there's something like
a NAS you can't install apcupsd on. NUT is less painless.

sounds like a pain in the ....

On Mon, 26 Aug 2019 17:59:30 -0700, tabbypurr wrote:

On Monday, 26 August 2019 13:25:36 UTC+1, Roger Hayter wrote:

I think anything that can run apcupsd can be networked easily to the
box controlling the UPS. Remakably painless. It's only worth using
NUT (which can allegedly follow an apcupsd server) if there's something
like a NAS you can't install apcupsd on. NUT is less painless.

sounds like a pain in the ....

I'm controlling three UPS units here with nut. I have done for years. It
just works.

Setting it up is a bit involved but not hard. There's a good README. And
once done, it's done.



--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me £1 a message.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
*lightning surge protection* - a w_tom conductor

On 27 Aug 2019 08:54:14 GMT, Bob Eager wrote:

On Mon, 26 Aug 2019 17:59:30 -0700, tabbypurr wrote:

On Monday, 26 August 2019 13:25:36 UTC+1, Roger Hayter wrote:

I think anything that can run apcupsd can be networked easily to the
box controlling the UPS. Remakably painless. It's only worth using
NUT (which can allegedly follow an apcupsd server) if there's something
like a NAS you can't install apcupsd on. NUT is less painless.

sounds like a pain in the ....

I'm controlling three UPS units here with nut. I have done for years. It
just works.

Setting it up is a bit involved but not hard. There's a good README. And
once done, it's done.

Assuming you have used APCUPSD Bob, how does NUT compare? Does it just
work similarly or does it come at the problem from a different
direction?

Cheers, T i m

On Mon, 26 Aug 2019 17:59:30 -0700 (PDT), wrote:

On Monday, 26 August 2019 13:25:36 UTC+1, Roger Hayter wrote:

I think anything that can run apcupsd can be networked easily to the box
controlling the UPS. Remakably painless. It's only worth using NUT
(which can allegedly follow an apcupsd server) if there's something like
a NAS you can't install apcupsd on. NUT is less painless.

sounds like a pain in the ....

So how would you do it, assuming you understood why it might be a
'good idea' to have say 3 machines (but only) on one UPS?

Machine one plugs into the UPS monitoring port and becomes the APCUPSD
'server'. The other two machines also run APCUPSD but are clients to
the server.

If the power fails the APCUPSD 'server' detects the failure and
changes it's status from Mains good to Mains off (or some such) and
the client machines also see this over the LAN and react as set (by
you).

On mine the two client machines shut down within a couple of minutes
(or sooner if the Server indicated the battery was already very low)
and the Server shut down when the battery was less than 50% remaining
capacity.

I'd have to say it worked well and was very reliable.

It also meant that you could minimise the 'cost' of having the
background load of the UPS, and the UPS itself, over 3 (or more,
depending on the draw) machines.

Cheers, T i m

On Tuesday, 27 August 2019 11:04:25 UTC+1, T i m wrote:
On Mon, 26 Aug 2019 17:59:30 -0700 (PDT), tabbypurr wrote:
On Monday, 26 August 2019 13:25:36 UTC+1, Roger Hayter wrote:

I think anything that can run apcupsd can be networked easily to the box
controlling the UPS. Remakably painless. It's only worth using NUT
(which can allegedly follow an apcupsd server) if there's something like
a NAS you can't install apcupsd on. NUT is less painless.

sounds like a pain in the ....

So how would you do it, assuming you understood why it might be a
'good idea' to have say 3 machines (but only) on one UPS?

I take it you completely missed the moment of mild humour.
Rest snipped


NT

On Sun, 25 Aug 2019 14:50:32 +0100, Scott wrote:

I was watching an item on TV about use of batteries to balance the
national grid. I have also heard it said that the supply is likely to
become less reliable with increased dependence on renewables.

I have always assumed that an uninterruptible power supply must be
energy inefficient for the same reasons as stand-by uses electricity.
Is this a correct assumption or does a UPS not consume any electricity
at all unless it is brought into use?

As an aside, could a power cut ever damage a modern computer (say if
you happened to be installing an update or defragmenting a disc when
it happened)?

I've had files corrupted which were being written to when a powercut occurred. Therefore I got a UPS and have never experienced the same again. I then realised since the UPS has much more output than the computer needed, I could run my lighting circuit off it aswell. My LED bulbs now last 5 years instead of 6 months. It not only removes spikes, surges, and brownouts, but it will adjust the voltage when it's wrong.

On Thu, 29 Aug 2019 15:21:20 +0100, "Commander Kinsey"
wrote:
snip

I've had files corrupted which were being written to when a powercut occurred. Therefore I got a UPS and have never experienced the same again. I then realised since the UPS has much more output than the computer needed, I could run my lighting circuit off it aswell. My LED bulbs now last 5 years instead of 6 months. It not only removes spikes, surges, and brownouts, but it will adjust the voltage when it's wrong.

Can that not depend on the UPS though? Some do provide some passive
filtering but only produce any output themselves when the power fails
('Offline').

Others are more as you describe where they are maintaining the output
themselves all the time and so can do as you say ('Online').

I believe there are pros and cons to both types. Offline consume less
energy as all they need to do is keep the battery trickle charged and
switch to the inverter output when required. There can be a switchover
delay and some equipment can be sensitive to this.

So, given that many old UPS's don't produce a very clean (non sine
wave) output, Offline UPS's can be better long term as they only
subject the equipment to such when they are called for (the equipment
running directly from the mains till that happens).

Later UPS's may produce a cleaner, more sinusoidal output etc.

Cheers, T i m

"T i m" wrote in message
...
On Thu, 29 Aug 2019 15:21:20 +0100, "Commander Kinsey"
wrote:
snip

I've had files corrupted which were being written to when a powercut
occurred. Therefore I got a UPS and have never experienced the same
again. I then realised since the UPS has much more output than the
computer needed, I could run my lighting circuit off it aswell. My LED
bulbs now last 5 years instead of 6 months. It not only removes spikes,
surges, and brownouts, but it will adjust the voltage when it's wrong.

I'm considering getting a UPS for my computers, router, Raspberry Pi etc
because our village gets an inordinately large number of supply
interruptions: I've logged 5 in the last week. Typically they only last a
couple of seconds, but that is enough to make computers reboot.

I've complained to phone number 105 (for Northern Powergrid) and been told
that it's due to "work on the HV supply", "bird strike on a cable", "tree
falling on a cable" and "lightning strike" (the last even when there's not
been a storm in the area). I think it's a random excuse generator. If "bird
strike" and "falling tree" are genuine, they must be *very* unlucky for
there to be 5 power cuts since 24 August - plus all the ones before I
started keeping a note of them.

Next time I'll ask to speak to someone more senior who can tell me *why* our
village is affected so badly by power interruptions, and what Northern
Powergrid are doing to make their system more resilient to such faults.

So far I've been very lucky to avoid corrupted files, because on one
occasion I was defragging a hard disc at the time the power went off, but
being NTFS it was more resilient to corruption, though the first thing I do
after each power cut is "chkdsk /f c:" for each drive letter just in case
(and I've never yet seen it say that it has had to correct any errors).

First rule of any UPS is to check periodically that the battery is holding
its charge, and to keep the battery charged. My wife bought a UPS when she
bought a PC about 10 years ago, and we never got round to connecting or
testing the UPS for about 18 months, by which time it was out of warranty.
When I tried it, I found that the battery would not supply AC mains even for
a 60 W bulb for more than about 2 seconds :-( We should have kept it
plugged in to keep the battery charged, and tested its output every so often
by switching off the input - that would have detected dead-on-arrival and
premature failure.