ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Recent Posts
Chinese motors rated 220 v 50 hertz
by gfretwell - 07/23/24 04:45 PM
100 Definitions: Accessible 2023
by gfretwell - 07/23/24 10:12 AM
100 Definitions, Likely to Become Energized, 2023
by gfretwell - 07/23/24 10:08 AM
240V only in a home and NEC?
by emolatur - 07/18/24 01:05 PM
2023 CEU Course
by gfretwell - 07/17/24 01:08 AM
Advertisement:-Left
Recent Gallery Topics:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 211 guests, and 32 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: Aug 2001
Posts: 7,520
P
pauluk Offline OP
Member
Quote
Electricity supply is expected to return to normal today following nationwide blackouts yesterday affecting half a million people.

Hundreds of thousands of homes and businesses across London, Cheshire, Merseyside and East Anglia were affected between 11am and 1pm yesterday.


Full story:
http://www.dailymail.co.uk/news/art...ants-shut-bad-weather-sweeps-nation.html

Horizontal Ad
Joined: Dec 2005
Posts: 872
Likes: 4
R
Member
Thanks for that info pauluk.
Was your area affected too ?

We have similar problems here soon in NZ. Hydrolevels low, profits up and not enough thermal capacity at the moment.
I will post when D day arrives in about 3 to 4 weeks.

Regards, Raymond


The product of rotation, excitation and flux produces electricty.
Joined: Aug 2001
Posts: 7,520
P
pauluk Offline OP
Member
We weren't affected where I am, although it seems that some towns in Suffolk (next county to the south) were blacked out, and there were also failures in mid-Lincolnshire (next county north/northwest).

Joined: Aug 2001
Posts: 7,520
P
pauluk Offline OP
Member
Reading from various sources, it seems that what happened is that the Longannet power station (about 2400MW capacity) up in Fife, Scotland, had an unexpected shutdown, and this was followed within 2 minutes by another unexpected shutdown of Sizewell B nuclear in Suffolk (about 1200MW).

The resulting loss of capacity brought in automatic load shedding to stabilize the network. Somebody on the IEE forum noted from UPS logs and the National Grid's realtime network page that the grid frequency had dropped right down to 48Hz.




Joined: Dec 2005
Posts: 872
Likes: 4
R
Member
The under frequency relays at least worked OK.

In NZ they are set to 47.8 Hertz for selected feeders and 47.5 Hertz for all feeders in substations of the local POCO Auckland distribution network, to avoid a complete blackout.

We tested all our UF relays about 2 months ago in preparation for an interesting wintertime with low hydro levels.


The product of rotation, excitation and flux produces electricty.

Link Copied to Clipboard
Advertisement:-Right

* * * * * * *
Tools for Electricians
Tools for Electricians
 
* * * * * * *

2023 National Electrical Code (NEC)
2023 NEC + Exam Prep Study Guides Now Available!

Member Spotlight
JoeKP
JoeKP
Berkley, MA
Posts: 144
Joined: March 2008
Top Posters(30 Days)
Popular Topics(Views)
323,572 Are you busy
247,890 Re: Forum
231,670 Need opinion
New Page 2
Powered by UBB.threads™ PHP Forum Software 7.7.5