There are (at least) two major UPS topologies in play.
One is where the power to the protected device is always made by the inverter and maintained at the correct main voltage irrespective of input voltage to the UPS. Useful in places where the local mains supply voltage goes up and down a lot depending on load.
The other is a pass through of input mains voltage to the load under normal conditions and an isolation relay plus cold start of the inverter within a couple of cycles of the supply failure. This is more than good enough for PCs. Mine can withstand a 1s blackout unprotected without any difficulty but kitchen white goods clocks cannot.
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L
Liz Tuddenham
A "Disconnection Rota" marker has recently started appearing on my electricity bill.
B
Bill Sloman
Only in the sense that it doesn't do anything unpredictable.
The point about inverter-based controls taking energy from grid-scale batteries (or feeding it into them) is that they can operate much faster. They can force the voltage at their connection to the grid to sinusoidal on a millisecond to millisecond basis.
If the current output from the rotating machinery dominates the energy being feed into the grid, that will happen. If most of the energy is coming from solar cells through inverters that isn't a useful way of looking at what's going on.
M
Martin Brown
You still get paper ones? I confess I haven't actually looked at my virtual "paper" electricity bill for ages. I use the online portal to check usage and how much they have taken in DD for prepayment.
Electricity companies have a nasty habit of always increasing DDs when the price goes up and never reducing them so that if you don't keep an eye on it they can borrow your money. Officially to smooth out winter.
I'll take a look on mine. I only have water and sewage as physical paper bills to satisfy what laughingly passes for "proof of identity" in the UK! The other utilities are on DD to get preferential rates.
I can't see why we would ever be inline for rationing power cuts though we are pretty much on the nexus where under all foreeable scenarios we have an oversupply of power that can't move any further south!
It might fail for over voltage though.
K
KevinJ93
When the coal miner's strike power usage reductions were in effect I was working at Marconi-Elliott in Borehamwood. We were not allowed to have the lights or heating on but it was permitted to use test equipment so we would huddle around our Tektronix 547 scopes to keep warm, they used to put out a lot of heat.
C
Carlos E.R.
Ah! Yes, I remember now, I have seen this before. It was the terminology that was confusing me.
Thanks.
T
Tom Del Rosso
That's what the Left fundamentally fails to understand.
T
Tom Del Rosso
It looks like they spent a lot more effort simulating climate than they did simulating the grid system.
M
Martin Brown
We also live on the watershed for that. Just far enough north to be on the copious Northumbrian water supply (intended for all the now defunct steelworks) but with sewage outflow going downhill to Yorkshire Water.
It has great advantages - Yorkshire Water has many leaks and not enough reservoirs so hose pipe bans are almost inevitable every summer. One particularly bad year they were moving drinking water in tankers from Northumberland Water to Yorkshire to maintain supply. When it gets really serious they have had to resort to stand pipes in the street.
Looks like this year will be a bumper year for drought orders as there hasn't been any significant rain here for nearly a month now and we have have broken record temperatures for May already. Reservoirs in sensitive areas are at abnormally low levels for this time of year.
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Fair enough. Where I live the water supply is the huge Kielder reservoir built to service a once thriving major steel industry on Teesside. Even if it didn't rain at all for a year we would still be on supply.
Next village is on Yorkshire and often get hosepipe bans in summer.
L
Liz Tuddenham
I still pay individual paper bills. Last year they sent me a ridiculous bill which they said was recalculated from several bills going back over more than a year. Their calculations were a load of nonsense and, after three hours working on it, a friend who is a retired accountant gave up in despair.
I made payment conditional on a satisfactory explanation of how they had calculated the bill. Then they started sending weekly automated threats of bailiffs being sent to recover the 'debt' and the damage they would do to my credit rating. I sent many letters asking for an explanation, which merely received standard replies that didn't address my questions. Eventually they ceased replying and I never paid the bill.
The government has now made that practice illegal, but if I had been on Direct Debit, they would have taken the money and I wouldn't have been able to get it back.
C
Carlos E.R.
I agree. But my current router, for instance, doesn't have the feature. Doesn't even log locally. It is supplied by the ISP. The previous unit did have remote syslog capability, so I used it.
It doesn't report current. There is "ups.load: 13", but no idea of the units.
Ah, no, no fan in mine.
C
Carlos E.R.
Yes, I have seen that name, online, on some units.
The DeepL translation is not good. The vendor said "on wait (out of line) or Standby (Offline)", the second part in English. Probably a translation itself. I'm thinking the "or" is because they used "Spanish term or English term"
Right.
At a telephone exchange I found one "online" UPS cascaded from an "offline" UPS, IIRC. Used on the control room hardware (displays and printers).
Yes, I have seen this. The house goes slightly "brown" and the UPS becomes active, I hear the clack of the relais and the buzz of the transformer.
Right, they call this "cold start".
This is more difficult to find from the specs. Price could be an indication.
Hah! The warranty is two years :-D
However, I do have another unit from this brand, and the battery did last longer. This particular unit uses two batteries, 24 volts, actually.
Usually, I stick a label outside where I write the date when I replace the battery, and the price, but on this particular UPS I don't see the label. So I don't know the actual duration. Maybe I put the label inside?
That's funny. My car battery is currently 6 year old, and going fine, according to the garage (they just checked it). There was some "sulphate" on the lead stud which I told them to check.
And here it is hot weather, for about 5 months a year. :-?
C
Carlos E.R.
Over here, it is not possible to not use direct debit.
C
Carlos E.R.
Yesterday I heard on the news that most cities in the USA are sinking down, due to water extraction from wells.
B
Bill Sloman
What the right fails to mention is that making money mostly involves cheating people. If you can do something more efficiently that other people you can make money out of it, but it's a lot easier to claim that you are more efficient and simply cheat.
The left goes in for detailed enquiries about what is actually going on, which the right like to characterise as officious invasions of privacy, and often subvert by tricks like regulatory capture.
Look up "rent-seeking" sometime.
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That's what Trump's tariffs are doing for American manufacturers - they can suddenly 10% more (or whatever) for their products than their foreign competitors, purely because they are American.
B
Bill Sloman
Simulating the climate is science, and nobody spends a lot on that. Simulating the grid system is business, if it is done right, but there are lot of different mechanisms active in regulating the grid, and most of them are commercial in confidence, so only the businesses that make the mechanisms know enough to be able simulate them, and it takes a regulatory agency to force all the businesses involved to get together to work out how their various mechanisms will interact.
Regulatory capture means that the agency is unlikely to force the businesses to do it.
C
Carlos E.R.
Not enough, apparently.
The hut they vandalized has a notice board that says all the cables are aluminum.
Uff.
Yeah, here too. They even tried to rip the railway catenary at some place. Some of those died on the spot.
So the brand name battery replacement for my UPS is actually cheaper than what I paid. Surprise!
Right, they are very heavy. Yep, the place above charges 5.25€ for shipping.
Right.
C
Carlos E.R.
Are they 12 volts each, or just one cell?
On phone exchanges I saw huge batteries, actually individual cells connected in series. 48 volts nominally, so 24 cells. I don't think they were gel types, they needed adding water now and then.
Some UPS say they can test the battery. Mine do not, or the software I have doesn't.
When looking at specs for a replacement UPS, possibly an Eaton, I saw they mentioned emitting a beep when battery is bad.
C
Carlos E.R.
Ah, ok.
Heh.
J
john larkin
Here in San Francisco you can do that, or wash a car, but the hose must have an automatic shutoff nozzle on the end. Of course nobody enforces that.
We rarely have lawns (real living ones) here, and no pools that I know of, which helps.
I hated mowing lawns. What stupid things.
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