Best Practice Electrical Setup

SaberX on 27/06/2018 - 02:29
Last edited 27/06/2018 - 02:34

Hi all. Have not much of an electrical wiring education and was just wondering if some could provide some input on best practice round the home when it comes to using electrical wiring i.e. power strips,surge protectors, double powerpoint adapters etc.

Basically i was in bunnings today looking for a surge protector powerboard as we'd run out of space on my dual powerpoint by my side of the bed. One used for phone charger,one for electric blanket and that left none for the laptop in bed or other devices.

It got me thinking:

1) what the minimum specs for a surge protector are. For now i settled on a 300 joule capacity arlec 4 point for $19 from bunnings. I just wanted individual switch ability for each point on board as i always felt paranoid pulling plugd out of boards turned on but where you weren't using the point and wanted to switch in another cord. and its 1.8m long. Comes with overload protection and all the standard.

2) what's best practice for linking different wiring, adapters and other adapters extending wall outlets to have teo or more points. My old practice for my bedroom back at my parents wss i ran an extension cord from wall outlet to which a surge protector connected into. I got this off cotd years back. Near 1700 joules so its a typical home entertainment surge board as comes with antenna and phone line slots etc. So more hard hitting.

Currently i also have a power strip added on one power point of this surge protector.

I cant find much online (as allt of conflicting advice on do and donts) except that using an extension cord in the US is frowned upon for permanent use. Particularly for connecting a surge board into to access a wall outlet. Supposedly it renders it non effective or a fire hazards for the extension?

Since i grew up extension cords were always used permenantly. It just isnt an ideal life to create a new PowerPoint outlets "closer". Or was our family just weird?

3) when should we be using surge protector power boards or even surge powerpoints with single or dual slots?? These typically are $7 from bunnings but only take 175 joules. Seems low in comparison to the 1700 joules on the home entertainment style power board i used back at my parents. Let alone the new arlec one i bought today was 300 joules.

Should i be buying a surge protector for our new fridge etc. We've grown up generally having no issues so wondering if we've been lucky or if direct to wall outlets is sufficient for most. Or should all wall outlets be fitted with a surge protector plug in which you then plug appliances or electricals into. Seems cumbersome though.

4) we turn off but leave electric blankets plugged in at night. Can a power surge (lightning strike) get through via your wiring to your non turned on electric blanket while your sleeping on it and cause a fatality?? Or if switch at powerboard point of contact is on and product switched off are you safe?

5)any other do and donts??can i use my double adapter with surge protection i.e. 175 joules to connect to the wall outlet then have the extension cord through it. So the extension
Cord is protected,then have the surge protector powerboard connected to the extension cord?

How does the power board connected to the surge protector powerboard which is in turn connected to the extension cord and then wall outlet work??

My main concern is safety and if they are going to "protect" as intended. Sorry i have no understanding of electrical requirements, amps etc. So would love a bit of clarification.

6)if anyone has a good brand or links of a good surge protectors to buy please do so. Particularly after individual switches and i think havin 2 or 3 m now would avoid the extension cord issue?

Thanks.

Electrical & Electronics

Comments

  • D C on 27/06/2018 - 02:45
    -1

    While you're in a pondering mood, why not ponder as to how many joules are in a bolt of lightning.

    • EightImmortals on 27/06/2018 - 08:26

      1 210 000 000.00 joules per second (J/sec)

      Great Scott!

      • [Deactivated] on 27/06/2018 - 15:57

        Wait watt?

        • EightImmortals on 27/06/2018 - 16:00

          I know right, I had to figure that out too, just call me Sherlock Ohms.

      • D C on 28/06/2018 - 11:14

        Haha, someone not in a pondering mood down-voted me.

        A friend of mine was sitting out the front of his house on day having a durry when lightning hit it. (The house, not the durry.)

        Or it hit nearby, he said it was hard to tell from the flash and noise.

        Destroyed pretty much every electrical item in his house (he obviously didn't have surge protectors - I didn't ask) and caused him to soil his favourite pair of Superman undies.

        Not being able to watch TV for a while is ok, but having your best underdaks ruined would be nigh unbearable.

        As other have pointed out, surge protector are a waste of time. If you do get hit by lightning, that's just something else they'll cheerfully destroy.

        • SaberX on 28/06/2018 - 18:31

          Understand that no surge protector is going to stop lightning strikes - it wasn't the point of the thread to be honest. It was more of protecting against what it states in terms of current fluctuations and surges that are more 'common'. I do openly admit not knowing what this coudl be caused by and frequency/chance, given I haven't had many or any appliances growing up that broke down from these power fluctuations/surges. I guess it's more of a thought that 'this protects against xxx' and therefore it must be better than using a normal power board with no surge protection.

          Definitely don't expect it to protect against strikes. But is the surge and/or overload protection not worth the $20 or $30?

        • D C on 28/06/2018 - 19:56

          @SaberX:

          But is the surge and/or overload protection not worth the $20 or $30?

          Nope.

          Australia has a pretty good power grid, anything it can't handle by itself isn't going to be stopped by your surge protector.

          Most electronics already has a filter or some sort build in. Microwave ovens usually contains the same MOV's as the surge protector, I've seen the MOV fail (shorting out) and that blows the fuse. One dead microwave. Easily fixed but many people don't bother. Washing machines are the same.

          Switch mode power supplies in pretty much everything these days are good at handle voltage fluctuations as well. Well, usually. You $1 USB charger might not.

          It may be worth putting one on audio gear if you're hearing clicks & pops caused by other stuff in your house, like the fridge starting up. That's probably not doing any harm though, it's just annoying.

  • Riczter on 27/06/2018 - 02:58
    +3

    Jesus… You want surge protector on your computer and hi fi setup, and any sensitive electronics but that's about it, you dont need it on every appliance. A lightning strike isnt gonna fry you through your electric blankets. Your house will be earthed. And if the earthing fails, I'm pretty sure no surge protector on the planet will hold back the full force of a lightning strike.

    A powerboard with individual switches are great if you are going to be plugging things in and out while the board is turned on. Extension cords with a powerboard on the end should be fine, make sure it is a board with overload protection, and make sure the extension cord is plugged directly into the wall, not into a double adapter, or another powerbord. A potential hazard is if you have two powerboards plugged into a single wall outlet with a double adapter, and then load both boards close to capacity. Each board on its own is fine within capacity, but the current going through the double adapter is almost double what it is rated to and these are very cheap and flimsy which can cause them to fail and melt into a pile of smelly plastic and burn your house down. Extension cords are fine in a permanent position, if you are running a powerboard at max load on the end then keep the extension cord length at 15m or less. Max safe load is 2400W/10A per powerpoint i believe

    Experienced sparkies please let us know if any of this advice is wrong, im only pulling this info from what little i remember from a sparky preapp tafe course i did a while back and may not have got it all right.

    • SaberX on 28/06/2018 - 18:39

      No expectation of a lightning strike protection with a surge board. Lightning strike via electric blanket - iw as only curious as i've heard of two cousins who felt an electric strike via their telephone back decades ago, so logically i thought an electric blanket (even if off) and connected to a powerpoint or board would transmit a shock through if you so happened to be sleeping in bed? Not sure how it works as I don't know my electricity, physics, or anything whatsoever to calculate or know about this, hence my question.

      Individual switches are for as you mentioned - pulling things out while it's on without worrying.

      Regarding when you can/can't use an extension cord, so you would say it is an outright no to use any appliance via an extension cord that is plugged into a powerboard socket? However if directly plugged into a wall outlet, you can still safely use a powerboard that is connected to this extension (on a permanent basis, year in year out)?

      Why does the use of say a double adapter to split an outlet, with one split going to the extension cord cause an issue? Provided you ad hoc use the second split point and not permanently is it an issue of overloading the double adapter, more possible than if the extension cord is directly plugged in? All new australian houses wall outlets would be grounded by nature anyway, with RCDs installed?

      Regarding your example: my wall point has two points (standard). One has the extension cord connected directly to the wall outlet which in turn has the surge board on the other end. The surge board then feeds one point to a power board (not surge board) - i understand a power board can be used on a surge board, but not a surge board connected into a surge board correct?

      THe second wall outlet then has its own surge board. Is this ok, given your example of a potential hazard mentioned two powerboards in one wall outlet, however I took it as being on the same double adapter, as opposed to the seperate points on the wall outlet.

      WIth your safe load of 2400W/10A so if a powerboard has 6 points, each one can load 2400 W/10A? Most everyday persons such as myself are oblivious to electrical ratings, we just plug it into the board, so i guess the hardest part for a non educated person who knows nothing about amps or watts is correctly using and loading it.

      It might explain though why the electrical heater on 1200W option doesn't fail, but the 2400W eventually (once its been going for abit and heating up the room for awhile) trips the powerboard (that feeds into the surge protector, which is connected to the extension cord to the powerpoint on the wall outlet). As i assume 2400W is the max that whole powerboard can use (all powerpoints on the board) at one time?

      • Riczter on 28/06/2018 - 20:11

        so you would say it is an outright no to use any appliance via an extension cord that is plugged into a powerboard socket?

        No I didn't/wouldn't say that.

        Basically you can plug any appliance into anything and daisy chain as many powerboards as you like, AS LONG AS the sum of the total wattage is under 2400W at the power point. However the normal person doesnt know off hand the exact current draw of every device they own, and how much resistance every contact and 1m length of cable adds to the circuit so a general rule of thumb to be safe is to not run powerboards off powerboards, whether they are surge protected or not. However I do it all the time, and as long as you make sure your powerboards have overload protection and you know what you are plugging in then you should be fine.

        Don't confuse overload protection with power surge protection. Overload will protect if you go above 10A/2400W on your powerboard, for example plugging 2 heaters in. Power Surge will protect against voltage fluctuations on the grid due to storms, accidents etc.

        Lets use your heater as a good example, while its running at 2400W, with nothing else on, and knowing that powerpoints are rated to 2400W/10A as are most electrical devices including double adapters, powerboards and extensions leads.

        So you Plug it straight into a wall, that's fine
        Plug it into a cheap double adapter. Slight risk, but should be fine.
        Plug it into a powerboard with overload protection, perfectly fine
        Plug it into a powerboard on the end of a less than 15m long extensions cord - should be fine. Extension cord and ends might get a little warm if its a cheapie. If its longer than 15m the extension cord may start to heat up a lot more, depending on how heavy duty the cable is.

        Plug 2 heaters into different powerpoints in the same room - should be fine. Most house circuit breakers i believe are rated to 20A?
        Plug 2 heaters into different points on the same powerpoint (for example a 2 gang powerpoint) - moderate risk, they are only rated to 10A.
        Plug 2 heaters into a cheap double adapter and plug it into one powerpoint - EXTREME RISK of double adapter melting.
        Plug 2 heaters into any combination of extension leads and powerboards with overload protection into a single powerpoint. Moderate risk. Hopefully the overload protection on a powerboard will save it, but if not, then expect melty melty.

        All your appliances will have their power output listed on them somewhere - but a good way to think is that if it outputs HEAT then it is going to have a high wattage. For example heaters, kettle, microwave, toaster, hair dryer, and even vacuum cleaner often have high wattage. So you are going to be fine if you just have this device on the end of an extension cord or powerboard with nothing else plugged in, but if you have other stuff plugged in and running and you add a heater or vacuum cleaner on the end, then you will likely have a problem.

        Plug high wattage appliances directly into the wall, or on their own extension lead or powerboard with other devices turned off.
        Dont run two or more high wattage appliances at the same time off the same powerpoint/powerboard/double adapter
        This means dont run your kettle and toaster at the same time as your microwave off the same double adapter.

        But feel free to have a mess of computer devices, or tv and highfi devices on a good quality powerboard with overload protection piggy backed to another powerboard with surge protection on the end of an extension cord plugged directly into the wall, that should be fine with only minor risk (from increased points of failure ie: loose plug/bad connection in one of the money powerboard sockets) as long as you dont plug the vacuum cleaner into the powerboard while it is all running.

        Hope that gives you a better idea of how it all works. If a device gives you amps instead of watts remember amps times volts = watts. And volts always equals 240 so 10A = 2400W. Your 1A phone charger is only putting out 240W but your heater on medium 1200W is putting out 5A and your 1000W microwave is putting out 4.17A.

        Just keep the load under 10A / 2400W and remove any weak links from the chain which means double adapters and cheap powerboards without overload protection unless you are damn sure that the power running through that weak link will definitely always be under 10A 2400W

        • Leeroy Jenkins on 04/07/2018 - 10:14

          Sorry I have to correct you on the "1A phone charger" bit. Your typical phone charger never draws 240W of power from the wall, that'd be crazy. You phone battery would probably explode. IA is output current, output voltage is usually 5V for USB, so 5V*1A = 5W. The input current of these chargers are usually at most 10mA from my impression.

        • Riczter on 04/07/2018 - 12:42

          Ah thanks for correcting me there :) I just assumed that because they are marked 1A that they would be 240W in the same way that 10A was equivalent to 2400W, but i forgot to calculate the output voltage as 5V rather than 240V :P

        • cloudy on 16/08/2018 - 23:04

          Wow, super duper thanks for the post, learnt a bit here, so quick question.

          I run my toaster and my kettle at the same time, both plugged into the same wall socket side by side. Am I reading you correctly that this is a risk?

  • [Deactivated] on 27/06/2018 - 04:07
    +3

    All seems very technical for bedside power. I just have a phone charger and a basic 6 outlet powerboard for keeping marital aids at 100%.

    • Domingo on 27/06/2018 - 09:49

      keeping marital aids at 100%

      I can't be the only one wondering - please elaborate!

    • SaberX on 28/06/2018 - 18:41

      I did get the surge board for next to th ebed. But I was pondering best practice for rewiring my bedroom back at my parents (i do visit at times) versus also setting up the powerpoints at our main tv. Currently the main tv uses one point and another for the mi box, however with the playstation 4 there and other devices i finally need to buy a surge board (or power board) for it. Which got me thinking as to when and where i can use extension cords vs power boards, vs doubel adapters etc, as I know nothing about the technical side of these things.

  • whooah1979 on 27/06/2018 - 05:57
    +1

    Backup your data every night on a thumb drive or a microsd. It’s the most effective solution and cheap as you know what.

    Please add tl;dr.

    • SaberX on 28/06/2018 - 18:41

      I do have occasional backups , nowhere near monthly, but i guess my main issues wasn't just data loss on a fried laptop but not having appliances blow or start a safety hazard i.e. burn the house down, electrocution or malfunction etc.

  • hawkeye on 27/06/2018 - 07:40

    According to UPS manufacturers most people lose their electrical equipment from low voltage.

    • SaberX on 28/06/2018 - 18:42

      For the electrical uneducated how would a 'low voltage' situation arise?

      • Riczter on 28/06/2018 - 19:23

        The house i'm in now has experienced a "brown-out" twice, once for over half an hour, and once for just a few moments. Where the supply in to the house is well below 240v, due to storm or accident with a power pole etc. Very eerie, all the lights went to 20% dim and were flickering, alarm system was trying to go crazy. A quick google told me to turn off all my appliance as it can be very bad for them, but fortunately doesnt seem to have caused any major damage.

  • mskeggs on 27/06/2018 - 08:18
    +3

    Don't measure electricity in joules unless you are doing physics. Appliances are marked in watts, volts and amps.
    Don't run high current items on a power board (heaters, irons, microwaves). Don't chain power boards together so the combined load is over 2000w.
    Don't run all your high current appliances at once, or you might trip a circuit breaker.
    Don't worry about electric blankets.
    The risk of damage from electrical surges is overstated in my opinion. I have lost a modem and a chromecast (but not the TV it was plugged into!) after a thunderstorm last year, and a fax machine in approx 1988. So over 40+ years I rate surge risk minimal. Obviously different if you live on a farm or in the tropics or somewhere with high risks. You can always make an insurance claim if expensive stuff gets damaged. So a surge protector is a fine idea but not essential.
    Note the surge protector does not offer any human safety protection, it is only for electronics.
    If your meter box does not have an RCD installed, it is a good idea to add one, as this minimises human risks of electric shock.

    • fantombloo on 27/06/2018 - 09:24

      Surge protectors often have their protection ability measured in joules since they are essentially limited-use (mostly one-time-use) devices that can dissipate particular power for a particular time. Power x time = energy (measured in joules). So OP is correct about protection ratings.

      But there is much more to consider than just a joule rating and I fully agree with the above comment that surge protectors are mostly unnecessary.

    • SaberX on 28/06/2018 - 18:48

      As thevofa mentioned I use "joules" as a measurement of what safety or use you can get out of it - being uneducated with electrics this was the best benchmark I guess I use to differentiate between the alternate surge boards on sale?

      How do I make sense of watts, volts and amps and relative to packaging of surge boards and knowing what appliances can be plugged in? Typical everyday person where I just plug whatever i need in, never had a problem. The only issue i've had is the electric heater which trips the overload on 2400W mode (after being running for awhile) yet I can leave it on 1200W indefinitely for a few hours.

      Why shouldn't/cant one run a heater off a powerboard? However, is it safe to use directly to the wall outlet due to the difference in construction of the underlying wires etc?

      You mentioned not chaining pwoer borads together to stay under 2000w, but how do I know how many watts my plugs are using? I.e. my extension cord to the wall outlet is connected to the surge board. THis surge board runs a typical alarm clock /bedside cloth, the laptop when in use, and in older times my study lamp. One point connects a further power board (not surge board) that sits by the side of my bed, which in turn i connect the electic blanket to, my phone charger (samsung s8) and the mrs uses the iphone charger when she is visiting. The heater then runs off this power board. As mentioned I haven't had an issue with the heater except in 2400W mode instead of 1200W mode.

      So based off this how would I rate or work out how much I am loading on the board? I agree too that alot of things my parents have had never died in surges, and I don't really understand how 'surges' or variations occur to damage items, i just read the surge board packaging and assume it is 'better than not having it'. Guess it's kind of like those suckered into extended warranties, it 'seems great' on the surface for the uneducated?

      So the surge protector would not help in terms of shutting off any surge, or overload if say you were holding your phone or using an item connected? SImilarly the electric blanket scenario in the event of a surge or lighting strike would not pose a safety issue if it was physically plugged into the board and you were in bed at the time? Just curious.

      Can't speak for my parents house built in the 2000s, but for a new house just built a yr or two ago (my own) this would by law have RCD int he meter box correct? And all wall outlets would be grounded?

      I only ask as a new laptop charger claims to be an original asus but i guess a vibration feeling (electrical vibrations per google) on the bezzel of the laptop when on. But my original charger (came with laptop that was bought) hsa no issue, so i presume the wall outlet is grounded, and the replacement charger is just not correct.

      • mskeggs on 29/06/2018 - 07:44

        Read weston's long comment(s) below and scubacoles link to the Dan's Data site.
        Surge protectors are generally worthless. The Dan's Data link shows the circuit layout, demonstrating why they cannot provide any additional human safety.

        You can add up the total watts by checking the labels on appliances. Watts = volts x amps if they aren't listed separately. note the labels show max usage. So, like your heater, appliances can happily work at lower capacity that will over load the circuit at full power.

        As a rule of thumb, limit any single wall socket to 2000w or so. That might be one heater, or 40 clock radios, or a mix of low power devices. Appliances that heat or cool use the most electricity, so are best on their own circuits (which is why the electric oven or Aircon often have a dedicated circuit).

        I don't know the current building standards for RCDs, and it likely varies. Best to look in the meter box.

  • ESEMCE on 27/06/2018 - 09:19
    +1

    Important to note that surge protecting power boards are a consumable and have a very limited lifespan before they become just a powerboard with no protection.
    The Surge protection technology (MOV) ages with EVERY surge absorption. In an electrically "noisy" area, it could only be months before the MOV fails closed circuit.

    Have a read here.
    http://www.dansdata.com/gz039.htm

    • mskeggs on 27/06/2018 - 09:53

      I haven't read Dan's Data for years, but it is still top shelf. Looks like he has stopped posting, however.

      • ESEMCE on 27/06/2018 - 10:41

        Nor I, this article apparently got an update in 2015 to add in new tech.

    • SaberX on 28/06/2018 - 18:50

      Thanks - aware it runs out, but my surge board still has it's light on for protection (1700 joules or so "home entertainment" style board) so I assume it hasn't been burnt out in the years it's been present.
      So perhaps variations and surges aren't common in our suburban areas.

      Would your expensive new fridge etc. have built in mechanisms to avoid surges and damage where you have no surge protectors in place?

      So main thing is to have an 'overload' protection board, so you don't overload and burnt/melt plastic? And surge is more of a fancy thing to have?

  • Domingo on 27/06/2018 - 10:03

    There are a number of "safety issues" with power boards, extension leads and double adapters.

    One of the issues with power boards, extension leads and double adapters is when people chain lots of them together - like this. You can end up with a lot of mechanical stress on your electrical connections and there is a low probability that something might go wrong, eg heat generation from one or more devices melts some plastic, some plugs become partially exposed and come into contact with something conductive, your dog pees on it etc.

    In general, a lot of the devices are made very cheaply and aren't very durable. Plus each extra connection is another point of failure, albeit low probability.

    The reality is that these problems aren't likely to occur, but there is a possibility that it will so if possible it makes sense to remove that chance. That being said I'm renting and don't have a powerpoint where I need one, so have an extension cable routed over and around a door frame to get power to a side table lamp.

    In OP's situation, he could get a 4 port power point properly installed instead, or perhaps a 2 port one with some 2.1A USB ports on it.

    • SaberX on 28/06/2018 - 18:54

      haha nothing that badly chained. But as mentioned I have the one wall outlet which I run a) a surge board off - the basic arlec ones from bunnings with 300 joules protection, that the inroom tv and ps4 etc run off so not much), and b) an extension cord which feeds into the main surge board. THis surge board then plugs in my laptop, table lamp, bedside clock, and most importantly and lastly a seperate power board which is situated next to the bed. This power board then feeds the bed's electric blanket, the occasional use of the electric heater, and mostly the two mobile phone chargers (samsung for me, iphone for the mrs).

      Would this be ok? As my limited understanding googling recently shows it's only an issue using an extension cord from a point on a surge board, but a surge board connected via an extension cord to the wall outlet is ok?

      And similarly to never use an extension cord or powerboard via a double adapter? I mean shoudl you only use a direct cord to a double adapter on a powerpoint? Whata re the 'rules of electrical wiring' is more my query?

      I just dont understand volts, amps and watts and how much boards take versus what our devices and appliances use - so I have no idea how to safely wire. Ovviously I dont do anything silly like the picture you showed haha.

      Powerpoint being moved or changed to two points isn't feasible physically, and moreso we wouldn't want to reinvent the room by physically moving it. hence the extension coard and 'boards' to reach the room, as its smaller than 12m2 so not the hugest. just a bedroom.

  • westom on 28/06/2018 - 01:46

    All useful answers will include numbers. For example, protection is always about where hundreds of thousands of joules harmlessly dissipate. Plug-in (magic box) protectors hope you never learn this so as to sell a $3 power strip with ten cent protector parts for $25 or $90. It is a profit center; not effective protection.

    Best protection already inside electornics will routinely convert hundreds of joules into rock stable, low DC voltages. It will convert that near zero joule into electricity to safely power semiconductors.

    Electronics are not sensitive. Electronics can be some of the most robust appliances inside a house. Anyone can learn why be asking for numbers. For example, a datasheet for a communication interface chips says it will withstand up to 15,000 volts without damage:
    https://datasheets.maximintegrated.com/en/ds/MAX1487E-MAX491…

    Routine is for interface semiconductors to withstand 2000 or 15,000 volts. You concern is the rare transient - maybe once every seven years - with potential to overwhelm that existing and robust internal protection. Protection that exists without using any protector parts.

    A plug-in protector must either 'block' or 'absorb' a surge. Obviously a 300 joule protector will never 'absorb' a surge that is hundreds of thousands of joules. That numerical disparity explains why so many power strip protectors create fires. Another concern with near zero joule prottectors.

    How does its 2 cm protector part 'block' what three kilometers of sky cannot? Same fact also explains why a millimters gap in a power switch does nothing to protect from surges. Appliances powered on or off remain at same risk. Nothing 'blocks' a surge.

    Telstra CO (central computers) suffer about 100 surges with each storm. How many times every year do they replace that computer? How many times has your town been without phone service for four day? Direct lightning strikes without damage was routine even 100 years ago. And unknown to a majority only educated in advertising, hearsay, wild speculation, subjective reasoning (no numbers), and fables. Effective protection always answers this question. Where do hundreds of thousands of joules harmlessly dissipate?

    A surge is an electrical current from the cloud to earth. And then maybe another four kilometers through earth to distant charges. That current is everywhere in that path at the same time. Nothing stops or 'blocks' that current. Effective protection never tries (plug-in magic boxes claim to).

    A direct lightning strike many blocks down the street (to overhead or underground wires) is a direct strike incoming to every appliance. Are all damaged? Of course not. An outgoing path must also exist to those 4 kilometer distant charges. Only damaged are appliances that makes that best outgoing path.

    Damage is often on an outgoing path - not the incoming one. TVs coax cable connection is damaged. The naive use wild speculation to claim a surge entered on cable. Instead, that was the outgoing path to ground.

    Every wire inside every incoming cable must connect to earth ground before entering. TV cable only needs a hardwire to connect to single point earth ground. No protector needed. That hardwire must be low impedance (ie less than 3 meters long).

    Phones cannot connect direct to earth. So Telstra (at your house and in their CO) must connect each wire, low impedance (ie less than 3 meters), to that same earth ground via a protector. That protector is only doing what the TV cable's hardwire does better. In every case, no protector does protection. That single point earth ground is where hundreds of thousands of joules harmlessly dissipate.

    Protection is always about how a surge current connects to earth ground without being anywhere inside. If that current is not inside, then best protection already inside every appliance is not overwhelemed.

    Nothing new here. Concepts to protect appliances are same as Franklin demonstrated over 250 year ago to protect church steeples. Protection is and was always about connecting that current to earth on a path that is more conductive and not destructive.

    Lightning is typically 20,000 amps. So a minimal 'whole house' protector is 50,000 amps. Because protectors that fail are scams. That 'whole house' protector must remains functional for decades after many direct lightning strikes. And that superior solution costs tens or 100 times less money per protected appliance.

    Above number defines protector life expectancy for many surges. Protection during each surge is defined by the quality of and connection to single point earth ground. Again, numbers must always be provided. It must be the one and only earth ground. That hardwire connection must be low impedance (ie less than 3 meters, no sharp bends, not inside metallic conduit, etc).

    World's best 'whole house' protector is useless without an earth ground. What should have most of your attention? Earthing. How to make that one 'whole house' protector even better? Upgrade its connections and earthing electrodes. A protector is only as effective as its earth ground.

    Why do so many recommend magic box protectors? Most cannot be bothered to learn any of this. Even though it was originally introduced in primary school science (ie Franklin).

    I guess that is enough to introduce well proven science. Once a surge is inside, then nothing will avert that hunt for earth ground destructively via appliances (powered on or off). Protection is always about where hundreds of thousands of joules are harmlessly absorbed. A protector is only as effective as its earth ground.

  • westom on 28/06/2018 - 01:48

    All useful answers will include numbers. For example, protection is always about where hundreds of thousands of joules harmlessly dissipate. Plug-in (magic box) protectors hope you never learn this so as to sell a $3 power strip with ten cent protector parts for $25 or $90. It is a profit center; not effective protection.

    Best protection already inside electornics will routinely convert hundreds of joules into rock stable, low DC voltages. It will convert that near zero joule into electricity to safely power semiconductors.

    Electronics are not sensitive. Electronics can be some of the most robust appliances inside a house. Anyone can learn why be asking for numbers. For example, a datasheet for a communication interface chips says it will withstand up to 15,000 volts without damage:
    https://datasheets.maximintegrated.com/en/ds/MAX1487E-MAX491…

    Routine is for interface semiconductors to withstand 2000 or 15,000 volts. You concern is the rare transient - maybe once every seven years - with potential to overwhelm that existing and robust internal protection. Protection that exists without using any protector parts.

    A plug-in protector must either 'block' or 'absorb' a surge. Obviously a 300 joule protector will never 'absorb' a surge that is hundreds of thousands of joules. That numerical disparity explains why so many power strip protectors create fires. Another concern with near zero joule prottectors.

    How does its 2 cm protector part 'block' what three kilometers of sky cannot? Same fact also explains why a millimters gap in a power switch does nothing to protect from surges. Appliances powered on or off remain at same risk. Nothing 'blocks' a surge.

    Telstra CO (central computers) suffer about 100 surges with each storm. How many times every year do they replace that computer? How many times has your town been without phone service for four day? Direct lightning strikes without damage was routine even 100 years ago. And unknown to a majority only educated in advertising, hearsay, wild speculation, subjective reasoning (no numbers), and fables. Effective protection always answers this question. Where do hundreds of thousands of joules harmlessly dissipate?

    A surge is an electrical current from the cloud to earth. And then maybe another four kilometers through earth to distant charges. That current is everywhere in that path at the same time. Nothing stops or 'blocks' that current. Effective protection never tries (plug-in magic boxes claim to).

    A direct lightning strike many blocks down the street (to overhead or underground wires) is a direct strike incoming to every appliance. Are all damaged? Of course not. An outgoing path must also exist to those 4 kilometer distant charges. Only damaged are appliances that makes that best outgoing path.

    Damage is often on an outgoing path - not the incoming one. TVs coax cable connection is damaged. The naive use wild speculation to claim a surge entered on cable. Instead, that was the outgoing path to ground.

    Every wire inside every incoming cable must connect to earth ground before entering. TV cable only needs a hardwire to connect to single point earth ground. No protector needed. That hardwire must be low impedance (ie less than 3 meters long).

    Phones cannot connect direct to earth. So Telstra (at your house and in their CO) must connect each wire, low impedance (ie less than 3 meters), to that same earth ground via a protector. That protector is only doing what the TV cable's hardwire does better. In every case, no protector does protection. That single point earth ground is where hundreds of thousands of joules harmlessly dissipate.

    Protection is always about how a surge current connects to earth ground without being anywhere inside. If that current is not inside, then best protection already inside every appliance is not overwhelemed.

    Nothing new here. Concepts to protect appliances are same as Franklin demonstrated over 250 year ago to protect church steeples. Protection is and was always about connecting that current to earth on a path that is more conductive and not destructive.

    Lightning is typically 20,000 amps. So a minimal 'whole house' protector is 50,000 amps. Because protectors that fail are scams. That 'whole house' protector must remains functional for decades after many direct lightning strikes. And that superior solution costs tens or 100 times less money per protected appliance.

    Above number defines protector life expectancy for many surges. Protection during each surge is defined by the quality of and connection to single point earth ground. Again, numbers must always be provided. It must be the one and only earth ground. That hardwire connection must be low impedance (ie less than 3 meters, no sharp bends, not inside metallic conduit, etc).

    World's best 'whole house' protector is useless without an earth ground. What should have most of your attention? Earthing. How to make that one 'whole house' protector even better? Upgrade its connections and earthing electrodes. A protector is only as effective as its earth ground.

    Why do so many recommend magic box protectors? Most cannot be bothered to learn any of this. Even though it was originally introduced in primary school science (ie Franklin).

    I guess that is enough to introduce well proven science. Once a surge is inside, then nothing will avert that hunt for earth ground destructively via appliances (powered on or off). Protection is always about where hundreds of thousands of joules are harmlessly absorbed. A protector is only as effective as its earth ground.

  • westom on 28/06/2018 - 01:50

    All useful answers will include numbers. For example, protection is always about where hundreds of thousands of joules harmlessly dissipate. Plug-in (magic box) protectors hope you never learn this so as to sell a $3 power strip with ten cent protector parts for $25 or $90. It is a profit center; not effective protection.

    Best protection already inside electornics will routinely convert hundreds of joules into rock stable, low DC voltages. It will convert that near zero joule into electricity to safely power semiconductors.

    Electronics are not sensitive. Electronics can be some of the most robust appliances inside a house. Anyone can learn why be asking for numbers. For example, a datasheet for a communication interface chips says it will withstand up to 15,000 volts without damage:
    https://datasheets.maximintegrated.com/en/ds/MAX1487E-MAX491…

    Routine is for interface semiconductors to withstand 2000 or 15,000 volts. You concern is the rare transient - maybe once every seven years - with potential to overwhelm that existing and robust internal protection. Protection that exists without using any protector parts.

    A plug-in protector must either 'block' or 'absorb' a surge. Obviously a 300 joule protector will never 'absorb' a surge that is hundreds of thousands of joules. That numerical disparity explains why so many power strip protectors create fires. Another concern with near zero joule prottectors.

    How does its 2 cm protector part 'block' what three kilometers of sky cannot? Same fact also explains why a millimters gap in a power switch does nothing to protect from surges. Appliances powered on or off remain at same risk. Nothing 'blocks' a surge.

    Telstra CO (central computers) suffer about 100 surges with each storm. How many times every year do they replace that computer? How many times has your town been without phone service for four day? Direct lightning strikes without damage was routine even 100 years ago. And unknown to a majority only educated in advertising, hearsay, wild speculation, subjective reasoning (no numbers), and fables. Effective protection always answers this question. Where do hundreds of thousands of joules harmlessly dissipate?

    A surge is an electrical current from the cloud to earth. And then maybe another four kilometers through earth to distant charges. That current is everywhere in that path at the same time. Nothing stops or 'blocks' that current. Effective protection never tries (plug-in magic boxes claim to).

    A direct lightning strike many blocks down the street (to overhead or underground wires) is a direct strike incoming to every appliance. Are all damaged? Of course not. An outgoing path must also exist to those 4 kilometer distant charges. Only damaged are appliances that makes that best outgoing path.

    Damage is often on an outgoing path - not the incoming one. TVs coax cable connection is damaged. The naive use wild speculation to claim a surge entered on cable. Instead, that was the outgoing path to ground.

    Every wire inside every incoming cable must connect to earth ground before entering. TV cable only needs a hardwire to connect to single point earth ground. No protector needed. That hardwire must be low impedance (ie less than 3 meters long).

    Phones cannot connect direct to earth. So Telstra (at your house and in their CO) must connect each wire, low impedance (ie less than 3 meters), to that same earth ground via a protector. That protector is only doing what the TV cable's hardwire does better. In every case, no protector does protection. That single point earth ground is where hundreds of thousands of joules harmlessly dissipate.

    Protection is always about how a surge current connects to earth ground without being anywhere inside. If that current is not inside, then best protection already inside every appliance is not overwhelemed.

    Nothing new here. Concepts to protect appliances are same as Franklin demonstrated over 250 year ago to protect church steeples. Protection is and was always about connecting that current to earth on a path that is more conductive and not destructive.

    Lightning is typically 20,000 amps. So a minimal 'whole house' protector is 50,000 amps. Because protectors that fail are scams. That 'whole house' protector must remains functional for decades after many direct lightning strikes. And that superior solution costs tens or 100 times less money per protected appliance.

    Above number defines protector life expectancy for many surges. Protection during each surge is defined by the quality of and connection to single point earth ground. Again, numbers must always be provided. It must be the one and only earth ground. That hardwire connection must be low impedance (ie less than 3 meters, no sharp bends, not inside metallic conduit, etc).

    World's best 'whole house' protector is useless without an earth ground. What should have most of your attention? Earthing. How to make that one 'whole house' protector even better? Upgrade its connections and earthing electrodes. A protector is only as effective as its earth ground.

    Why do so many recommend magic box protectors? Most cannot be bothered to learn any of this. Even though it was originally introduced in primary school science (ie Franklin).

    I guess that is enough to introduce well proven science. Once a surge is inside, then nothing will avert that hunt for earth ground destructively via appliances (powered on or off). Protection is always about where hundreds of thousands of joules are harmlessly absorbed. A protector is only as effective as its earth ground.

    • SaberX on 28/06/2018 - 19:17

      All useful answers tend to be posted 4 times… haha.

      Regarding your opening example - while we can't imagine the huge joules of a lightning strike being brushed off by any protector I was wondering perhaps that having surge protection would halt any issues with the surge or volatile power of a lesser nature(That they advertise on the packs). I don't know if this arises from the power grids fluctuations or other issues on the board, but I was curious if it is a probable reality or like extended warranties a big rort?

      So what you are saying is your samsung fridge, laptop charger, tv etc. are designed already with internal components that can withstand those 15000 volts? And as I know nothing about voltage, amps or watts, is that a decent number for any typical non power strike related power surge - that may be caused by a faulty appliance or electronic, a power trip, or issues with the power grid surging?

      Understood a 300 joule wont protect agianst significant surges, but going from 300 jouels to say a 600 joule will either at least protect from more everyday power fluctuations or surges due to issues in the grid or power system, as opposed to lightning strikes and other more 'powerful' surges where they obviously wont block or absorb?

      Would a power overload powerboard switch off when a large surge comes through to prevent transmision of such a surge to any human contact safety wise?

      Understood that a gap in the power switch can easily be jumped by a surge and go through on/off appliances, woudl that imply that the electric blanket being plugged in woudl be a safety hazard on stormy nights and best to unplug your blanket prior to going to bed? Or is the human risk of electrical transmission non existing?

      You mentioned the Telstra Co example and asked where do hundreds of thousands of joules harmlessly dissipate? I am abit lost where? Are you saying that even years ago when all this advertising spin didn't exist that the natural grounding of a house served to dissipate these hundreds of thousands of joules? Otherwise what is your explanation on that?

      Coming from a non educated/technical background on electricals you mention alot about grounding. But aren't all powerpoint outlets to wall conencted to earth? So by nature whatever you connect to that - powerboards, surge boards, and appliances would less likely be damaged in a large surge (lightning strike etc) as it will find its way out to ground/earth as the easiest path?? Or an I interpreting that wrongly? You mentioned the protector will only be as good as the earth ground, however coudl you explain taht? As I thought each new house just has a grounded rod/earthed portion, that all owerpoints connect to? So isn't it a standardises thing, or can you introduce better 'earthing'?

      Thanks for your detailed explanations. Sorry some of the more technical aspects are 'lost' on my uneducated mind, but I did learn abit and it will probably be clearer in time.

      Relative to all your information about protection and knowledge though how about general electrical do and donts? I.e. some are advising not to connect a surge board to another surge board, and that i can use my surge board via an extension cord to the power outlet, but not the other way around (i.e. surge board direct to outlet, and an extension cord being plugged into surge board)?

  • westom on 28/06/2018 - 23:45

    The web site would only accept commands but not return a display. By the time a working connection was established, other 'copies' could not be deleted. And so it was posted every two minutes during the interruption.

    Surges that are tiny enough to not damage a protector routinely do not damage any appliances.

    Many appliances such as toaster, RCD, or dishwasher may be less robust. Electronic appliances typically are most robust. But again, a surge large enough to damage some is routinely too large to be 'absorbed' by a power strip protector.

    View datasheets for MOVs. A 300 joule protector confronted by a surge (more than 300 joules) means voltage on that MOV (if it fails) will increase to about or above 1500 volts. That is 1500 volts on the MOV and on nearby appliances. Effective protection means no such current is incoming to that appliance and protector. Therefore voltage stays well below what any appliance can withstand.

    15,000 volts was a better interface. All ethernet should withstand at least 2000 volts. Electronics (ie computer, TV) are typically some of the most robust appliances. A surge too tiny to damage most appliances should routinely destroy near zero joule power strips.

    A minimal 'whole house' protector is 50,000 amps. So a 20,000 amp surge does not create a protector destructive surge. That and a tinier surge does not result in a massive voltage also incoming to appliances.

    Also apparent in that datasheet are numbers for a typical surge. The 8/20 usec transient is completely ignored by any fuse or circuit breaker. Fuses / circuit breakers take tens of milliseconds and often seconds to trip. Well over 300 consecutive and destructive surges could pass through a powerboard long before any fuse or breaker trips. Those powerboard components trip AFTER damage happens. Fuses and breakers exist to protect humans after appliance damage has happened. Numbers say those cannot protect appliances from surges.

    Is an electric blanket a concern? Again, it is electricity. A surge current cannot exist if the outgoing path also does not exist. If a surge finds a better path to earth via the dishwasher or central air, then it need not find one via a bed. However if a mattress and frame makes a better connection to earth via electrically conductive concrete, then risk is higher.

    I have never heard of anyone shocked by a surge in an electric blanket. But theoretically it can happen.

    For example, lightning struck a tree. Boy scouts sleeping pointed towards that tree suffered severe shocks. Others sleeping tangential did not. Current down the tree, in earth, came up via the head, used a more conductive body to get farther from the tree, and then went back into earth via feet. Those who suffered harm made a better conductive and outgoing path away from that tree to earthborne charges some 4 kilometers distant.

    Damage to appliances or harm to a human is always about both an incoming and the outgoing path to earth. Surges hunt for (and damage) what makes a better outgoing path. Same for a body under and electric blanket. What is the incoming and outgoing path?

    Powerpoint safety ground is maybe 0.2 ohms resistance. And 120 ohms impedance. Impedance (not resistance) is the relevant parameter. Assume a tiny 100 amp transient is incoming to that protector. 100 amps times 120 ohms means that protector and attached appliances are at something less than 12,000 volts. Why less than? Because that current will find other destructive paths to earth via any nearby appliance.

    An IEEE publication demonstrates this. A protector, too far from earth ground, earthed a surge 8,000 volts destructively via a TV in the adjacent room. The term 'low impedance' was defined by a number. Wire length (not thickness) is relevant. A low impedance connection to earth is typically less than 3 meters. Every cm shorter increases protection - lowers that impedance to earth.

    Sharp wire bends, splices, and metallic conduit also increase impedance - reduces protection. So that a current is less likely to hunt for earth ground via an electric blanket, that connection to earth must be on a hardwire that goes up over a foundation and down to earth. Hardwire is too long and has sharp bends. Best to connect through the foundation and down to earth ground electrodes. Impedance (not resistance) is the relevant parameter for effective surge protection.

    How many wires inside a phone line? Two? Both must connect to earth. How many wires inside the AC power cable? Three? Four? Only one makes a direct connection to earth. Others must make that low impedance connection via a 'whole house' protector. If any wire (automatic lawn sprinkler or remote electric gate) enters without making a low impedance connection to that earthing electrode, then all protection can be compromised.

    And it must be single point earth ground. An AC utility demonstrates good, bad, and ugly (preferred, wrong, and right) solutions at:
    https://www.duke-energy.com/energy-education/power-quality/t…
    Then select Tech Tip 8.

    This can also be explained by those Boy Scouts. If one was standing with feet together, then no outgoing path - no shock. If one is standing with legs apart, then a conductive path is up one leg (one earth ground connection) and down another leg (the other earth ground connection). Legs apart means no single point earth ground.

    Protection for a house is similar. Best connection to earth ground must be at one point.

    Had those scout been standing inside a buried wire loop even with feet apart, then both legs connect to a same earth ground. Same applies to a house. If a single point earth ground is so large as to surround a house (ie Ufer ground), then the entire house is inside a single point earth ground. An outgoing path is also the incoming path. So no electricity exists.

    A surge could be incoming on a utility wire and outgoing to earth. Or a surge can be incoming from earth electrodes on one side of a building - outgoing via earthing electrodes on the other. Damage from either path is averted by the single point earth ground. And again, it is always about both an incoming and another outgoing path.

    Another example. TV cable was connected low impedance to earth before entering. So that had best protection. Lightning strikes AC wires far down the street. Incoming to all appliances. Best outgoing path was via the TV and its properly earthed TV cable. Lightning, all but invited inside, found the best path through a more robust appliance. Damage was on the TV coax connection (not AC power connection).

    Observation assumed a surge was incoming on TV cable. A mistake made by not always asking for both an incoming and outgoing paths. Incoming on AC mains. Outgoing to earth via a properly earthed TV cable. Damage is often on that TV cable or HDMI port connections. Current passes through everything in that path. But typically only damages one part in that path.

    Your questions are spot on target. I wish more would be so curious as to challenge myths routinely promoted in advertising (without numbers).

    Other human safety factors. Daisy chaining power boards is a fire hazard. A fire last April in Trump Tower (Manhattan) was directly traceable to daisy chained power strips. Reasons why are too complex to explain. But power strips must not be daisy chained so avert a fire. And power strips must also have a circuit breaker.

    Extension cords are typically for temporary service (ie 30 days). Safe wires are inside walls where motion does not compromise the conductor.

    One more frequent source of fire is extension cords in bedrooms. To detect and quash the resulting arc from extension cord failure, AFCI type breakers were first required for bedrooms. Arcing occurred when extension cords move too much or are compromised by heavy furniture (ie rollers for a bedframe).

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