UK National Electric Grid has changed to DC

It was 49.something when I posted, the history doesn't show any real problem, there seem to be minor excursions below the target 49.8Hz every few days.

Brian Gaff snipped-for-privacy@gmail.com wrote

Dramatically reduced losses, particularly with under water links and so that the stuff at each end doesn't have to be synched frequency wise.

Yes, but still worth it.

No, due to the ease of going from the very high voltages that are needed for the main transmission lines to the much lower voltages actually supplied to houses etc.

Because they are all leaden footed and exhausted by the time they have ppowered all your crap, and they don't work for nothing

The one from Norway is a bit sickly at the moment so NG have asked for a coal-fired power station to fire up because the lack of wind and high demand for air-con is putting a strain on the volts.

Meanwhile the old Redcar steelworks plant that is supposed to be the site of the factory that will build the cables that are going to bring DC power from North Africa to the UK seems to be embroiled in a huge corruption probe. No surprise there.

Redcar? That's on the North East coast of England - not where you'd expect a Moroccan undersea cable to make landfall. The map indicates North Devon.

'Four cables each 3,800km long' it says. I'll believe it when it's finished! They can't even decide on the link to Iceland, 'Icelink', only 1,200km long. And what ever happened to Desertec, the scheme to bring power from the Sahara across the Mediterranean and into the European grid? Died a death in 2015, that's what happened, just as Icelink is dying (if not actually dead), and as will this Morocco scheme. It's just another pipe dream to separate the unwary from their money.

What's Redcar got to do with it? The last I saw was that there might, just might, be an optical fibre cable factory built there. Not quite the same thing.

Building the cables isnt the same as where the UK end of the cable makes landfall.

When you're entering that thing, how do you know it's purged enough to be safe for entry ?

Paul

I suppose your inability to construe a perfectly sound sentence in English is sadly not atypical for a rabid EU supporter, but perhaps if you were to read the post again, you might just possibly arrive at the meaning that is crystal clear to everyone else.

You can use your Kill-O-Watt meter, to sanitize the baloney seen on the web pages. For example, my meter only has one digit after the decimal, but right now it varies from .9 to 0 and seems to be ever so slightly below nominal. Which could be measurement error on the instrument as much as anything (since the waveform comes off a Hall Probe and not off a transformer winding).

Using your Arduino, you can measure the time interval from rising-edge to rising-edge, and with the time interval, get a value for instantaneous frequency. Then filter that to make a gauge for yourself.

Paul

I can't answer that question, as I was never around for that part of the process. I guess that having purged the Hydrogen with CO2, you then circulate fresh air for some time. Air sampling kit is probably the key.

Chris

My unit cost is calculated to 4 decimal places.

It doesn't mention Redcar at all.

Check for hydrogen at the purge outlet, it will be ducted out the roof of the building.

The reason I mention that, is people have been killed at places like the shipyard, by entering a tank where the gas state is an unknown. Maybe two guys go down inside the tank to clean it, are overcome by whatever gases are still in there, and they die. And there is no third guy up top, watching them and sounding the alarm when they fall over.

There are hand-held detectors of course, and those can be configured for specific gases. Some of the sensors in those, respond to more than one gas type, but by putting a filter module in front, and having a pump pull air through the filter and up against the sensor, you can make the sensor more "gas specific", like CO2, or H2S, or CO, or whatever. A good one of those, costs around 1000, and you can change out part of it, and make it sense something else. Heating technicians usually carry one of those for CO, which they use to "condemn" customer heating devices. A home CO detector might detect 25 ppm on a good day, while the hand-held device can detect 1-2 ppm CO (a tiny combustion leak).

Paul

generally a few farm workers every year die in sludge tanks etc

During my time at Eggborough power station, hydrogen was not a problem. However, on one occasion I was pointed towards the three enormous power terminals in the bottom of the now empty stator casing, which were still covered in remains of the old jointing compound and needed to be prepared for the new stator connections. I was simply given a bundle of rags and a can of trike and left to it. I wondered why I was getting a little light-headed.

Chris

Safety at work requires a risk assessment to be produced stating the hazards and what protection remedies are in place. I have been in vessels that had been previously pressurised with CO2, but were blown down and purged with fresh air for 60 minutes. Detector details specified were in place and listed on the risk assessment. Also a confined space clearence had benn signed by a responsible person.