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Biggles – 1 minute ago » …
This sort of statement will lead people into a false sense of security…
Dead right (literally). I had a microwave oven, in its first year, sparking and filling the kitchen with smoke. It only stopped drawing current because the transformer burned out. The correctly rated fuse did not blow. If there had been any combustible material adjacent I would have had a fire to deal with.
Quote:If what you are saying is correct then I can only assume I have a ‘short good line’.Biggles
Go to http://speedtest.btwholesale.com/ and run the speed test. Now click the Further diagnostics tab – it will show you what your download IP Profile is. For short lines it should be what you are paying for as all lines can go up to 80-100Mb/sec (Faster Broadband). For longer lines, it should be the maximum usable speed without too many errors.
Annoyingly, they recently removed the upload IP Profile value from the page.
Be aware that some ISP’s limit the upload to 2Mb/sec whereas other don’t, and it is then about 25% of the download speed.
See attached for speed vs distance. Note the distance is the cable length and in towns, cables tend to follow the street grid to the green cabinet. I am 800 metres from my green cabinet and I am getting 39 Mb/sec down and 10 Mb/sec up. But I recently had my “grotty, old, noisy, waterlogged? cable” replaced with a nice shiny new one, which goes via telegraph poles and misses the underground run
[Moderator – sorry – a bit off topic but I trust useful to many …]
[attachment=48118,648]
See Fire Statistics Great Britain: 2013 to 2014 for an analysis of what is most risky.
JohnH77 – 13 minutes ago » </cite…Go to http://speedtest.btwholesale.com/ and run the speed test
OK, I’ve done that (not for the first time). It told me exactly what I already knew, and does not move the discussion on “switching off” forward one bit.
Pollensa
I was answering Biggles’ question – that is why I headed it Biggles.
Pollensa
Quote:The correctly rated fuse did not blow.EDIT: See correction in later post …
The fuse is there to protect the house wiring … if the fault does not generate sufficient current to blow it, it won’t blow.
JohnH77 – 24 minutes ago »
Go to http://speedtest.btwholesale.com/ and run the speed test.
Interestingly number 5 in the list of things to do before the test says re-boot the router by powering it OFF. Number 8 says it could take up to 10 days for the line to train up to its full speed but nowhere does it say the router has to be ON continuously for that period. Number 8 also suggests further speed test during this period may not reflect the final speed of the line, as number 5 says re-boot the router before a test that sort of suggests to me that the router does not need to be ON continuously.
Quote:number 5 in the list of things to do before the test says re-boot the router by powering it OFF. Number 8 says it could take up to 10 days for the line to train up to its full speed but nowhere does it say the router has to be ON continuously for that period.Biggles
1 You are asked to reboot the router to make sure it is working properly.
2 The exchange does not know you have rebooted your router. All the exchange knows is that the connection has died. It assumes this is a fault and then retrains the line when connection is re-established.
3 If you switch the router OFF, you disconnect the line. When you switch it back ON, it reboots – see point 2!
“Training the line” can only take place when the router is on as it is a process where the exchange increases the speed until the error rate reported by the router is unacceptable. Training is really the wrong word – it should be “optimises the speed of transmission”. So, you can safely take it that you should leave the router on.
4 It could be that more modern equipment takes a shorter time to retrain the line following a loss of connection.
5 The IP Profile is dynamic in that if you get interference on the line and the error rate goes up, the transmission speed is reduced until the error rate is acceptable. When the inteferenece reduces, the speed is allowed to rise either until the error rate becomes unacceptable, or the ISP cap is reached.
JohnH77 – 13 minutes ago »
The fuse is there to protect the house wiring …
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Rubish, the fuse is to protect downstream not upstream. The house wiring is protected by fuses/trips at the consumer unit.
True – I should have said the appliance cable as well.
The 30A in the consumer unit protects the house ring, and the appliance plug 13A, 5A, 3A, 1A fuse protects everything after the socket, but cannot be assumed to blow before the appliance catches fire. It is a slow blow fuse to cope with startup current surges (often 2x or more than the fuse rating) in transformers, motors etc.
Appliances (especially electronics like amplifiers) often have smaller, quick blow fuses on the PCB at lower current levels to protect the actual appliance electronics. These fuses are intended to blow before, for example, the power output transistors fail – the heat sink inertia keeps them cool enough even when massively overloaded due to a short circuit for the time it takes the fast blow fuse to blow and protect them.
The fuse is actually to protect the appliance flexible cord. It’s time related characteristic is such that any fault that could cause the cord to fail will blow the cartridge fuse first.
bs1362 fuse time current characteristics
No fuse will protect a high impedance internal fault where the fault current could actually be less than the normal current. I wouldn’t however expect a router to have any sort of signficant fire risk. Billions across the world are left on 24/7 (Anyone ever recall a report of one starting a fire ? ). Comparing one to say a tumbler dryer is frankly derisory. Tumble dryers catch fire because combustible fibres from the clothes get trapped in the exhaust system. Restricted air flow and inadequate air flow monitoring is a recipe for a fire. Miele tumbler dryers turn off if the air flow falls significantly.
Routers are generally connected via a power block using low voltage DC. In this case the output is near certain to be current limited to a value that will restrict the energy available to a level with insufficient energy to generate any significant heat in the block itself or the router. Bit like expecting a short circuited USB cable to generate a fire. It won’t get slightly warm.
JohnH77 – 15 minutes ago » …2 The exchange does not know you have rebooted your router. All the exchange knows is that the connection has died. It assumes this is a fault and then retrains the line when connection is re-established…4 It could be that more modern equipment takes a shorter time to retrain the line following a loss of connection.
You’re cutting-n-pasting again. Facts might lend some weight to your argument. You know, experience in the industry, your own experience at home, research, documented experiments on the net, etc.
As to fire hazards, some items are designed to be left on 24 x 7, and can safely be left on. I believe routers to be designed for 24 x 7 operation and I treat them as such. So too are items designed to be left in standby.
Other items are not designed to be left on 24 x 7, and I treat “charging my mobile phone” in that category – it should not be left on 24 x 7.
Cheap mobile phone/laptop chargers from auction sites are a potential disaster as they often do not comply to UK safety standards. A non-manufacturer’s charger can overcharge a lithium battery with too high a current and you do not want to do that. Search youtube with lithium battery fire overcharge or watch Overcharging LiPo battery
grahamlthompson – 16 minutes ago » …..
Routers are generally connected via a power block using low voltage DC. In this case the output is near certain to be current limited to a value that will restrict the energy available to a level with insufficient energy to generate any significant heat in the block itself or the router. Bit like expecting a short circuited USB cable to generate a fire. It won’t get slightly warm.
I agree Graham that the router itself is not likely to be a problem. However the power supply being the thing that is plugged into the mains could be a risk in the event of an internal fault. My personal view is that anything unnecessary has mains removed when I’m out. As my internet speed does not show significant change between router switch-ON and being ON for a long time, the router goes OFF. I’ve known people leave their microwave ON when they go on holiday, is that just in case the burglar fancies a snack???
Biggles – 2 minutes ago » … My personal view is that anything unnecessary has mains removed when I’m out. As my internet speed does not show significant change between router switch-ON and being ON for a long time, the router goes OFF…
Yes I agree, if a technical case can be made for leaving something on (obviously a fridge/freezer, PVR etc) then OK. No case can be made for the router, so I switch it off.
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