On Fri, 2014-10-03 at 07:46 +1000, Stephen Morris wrote: > I'm in Australia too. The electronic store I bought the powerboard > from tells me that a 2000W room heater, which draws 8.3 amps, if > plugged in to a powerboard will weaken the surge protector and destroy > the circuits, which probably explains why the surge protector kept > tripping when the heater had been in use for some time. Bad advice... A surge protector does its work when the mains voltage goes above normal, and does *NOTHING* at other times. When you plug devices into a surge protector, such as your telly, they are not drawing current through the protective device, your telly is connected directly to the mains, in parallel with the surge protector. The protective device sits across active and neutral, and shunts any excessive voltage and current together, should the mains supply go high (a surge). If the surge is high enough, the protection device will blow a fuse or circuit breaker (because they blow under high current conditions). Hopefully, it trips the breaker while the surge is building up, before it reaches a level that can fry other things on the circuit. However, some devices, may be fried before a surge protector kicks in. Your telly might not like being run on 255 volts (a surge above the nominal 240), but your surge arrestor might only activate at 260 volts. They are a bit of a false economy, for that reason. Our mains is nominally 240 volts, regulated to about +/- 10 volts, so all mains powered equipment must be able to run normally from 230 to 250 volts, at least. I've forgotten the specs for the range of AC voltage that the mains may surge up to without it being considered a fault condition, but some rather poorly built modern appliances don't cope with it, and most surge protected power boards don't kick in until *above* that point, too. The average surge protected power board doesn't really protect you against small (yet still destructive) mains surges, they're more designed to shunting seriously high surges that can cause fires in equipment (nearby lightning strikes, fallen power lines onto other power lines). You'll probably still get wrecked equipment, but it'll go splat, and quickly finish, rather than catch fire and burn under a prolonged severe surge. You really want surge protection at the mains supply to the house. Have everything protected, including all the wiring in your walls. A large surge can burn all the house wiring, which can be catastrophic for the modern house which isn't all brick walls inside and out, but made from flammable materials. Simple surge protectors (as found in most power boards) can wear out, eventually. You get lots of little surges on our mains, which take their toll, over the years. You'll often see a little red LED on these devices, supposedly to show you that the surge protector is still working, and to tell you to throw away the board if the indicator LED has failed. What they can do is wear out circuit breakers. Having an over-zealous surge arrestor continually shunting lots of current, means that the breaker is being stressed. These surge arrestor boards are really trying to solve a wrong problem, to use bad english. Our mains can fluctuate, quite a bit, and every appliance sold on our market should be able to deal with that, on their own. If your telly can't handle occasional mains spikes up to 270 volts, for instance, it's badly manufactured. -- tim@localhost ~]$ uname -rsvp Linux 3.16.3-200.fc20.i686 #1 SMP Wed Sep 17 23:07:44 UTC 2014 i686 All mail to my mailbox is automatically deleted, there is no point trying to privately email me, I will only read messages posted to the public lists. George Orwell's '1984' was supposed to be a warning against tyranny, not a set of instructions for supposedly democratic governments. -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
