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Send message Joined: 24 Dec 19 Posts: 31 Credit: 35,160,621 RAC: 118,366 |
What defines someone as a narcissist? Overview. Narcissistic personality disorder is a mental health condition in which people have an unreasonably high sense of their own importance. They need and seek too much attention and want people to admire them. People with this disorder may lack the ability to understand or care about the feelings of others. |
Send message Joined: 7 Sep 16 Posts: 262 Credit: 33,830,074 RAC: 23,996 |
*shrug* Don't come into this thread if you don't want Peter and I duking it out over wiring standards? That's about all it is anymore. It's not particularly off-grid focused. I've nothing interesting to say on that front, the LFP battery bank is behaving very well. |
Send message Joined: 9 Oct 20 Posts: 690 Credit: 4,391,754 RAC: 6,918 |
Yeah it shouldn't and I don't know why, I just add more cable where there's a problem.GPU feeds, 12.6V, 4AWG ring. More the connections get hot.The connections shouldn't be getting that hot - usually that indicates a poor crimp job, though if you're using aluminum wire (aluminium, however you want to spell it, same material - Al, of some reasonable alloy), you've likely got some oxidation issues going on at the connection. Oxidized copper conducts. Oxidized aluminum doesn't, and a high resistance connection makes for a lot of heat, and tends to make the oxidation issues worse until something stops working - or, more often than it ought, catches fire (I've seen research that the number of "thermally faulty" outlets in a fleet of houses with aluminum wiring vs copper is about 50x higher for aluminum - and that's before you get into the long term behavior of the wire, which is "less agreeable" in terms of work hardening, thermal hardening, etc). There are reasonable places to use aluminum wire, but I'd argue (as a serious DIY sort) that aluminum wiring is best left to people doing it professionally, because it really helps to have things like explosively welded lugs on the end of large gauge aluminum wiring (they literally weld the lugs to the wire with explosives, and there's no way for it to oxidize at the joint as the metals are firmly bonded). If you try to treat it like copper wire, you'll have a genuinely bad time of it eventually, because it's not well behaved like copper is - it work hardens more easily, it's more prone to stress fractures and cracks, and you pretty much can't use it in screw terminals for the long term, because the thermal expansion and oxidation behavior will eventually make your screw terminals glow with any serious power through them.Some of us are short of money and make do. Al wire is a hell of a lot cheaper. Or just use regular stranded cable and skip the fine stranded for interconnects. I've got a range of good crimping tools, to include a DC wire crimper that will do up through 0000AWG or maybe a bit larger.I always use stranded, solid core is a bitch to work with. Not sure why anyone uses it really. It's like folk who buy straight screws instead of pozidrive. Wiring up high loads with "cables laying around," where you don't know the wire gauge, haven't calculated loads, etc, is the sort of "casually sloppy with high power things" I'm criticizing you forI checked the cross sectional area with callipers. in the sense of claiming that you don't have enough electrical background to be able to have any interesting conversations about your shortcuts. At least in your posts here, you come across as having a "Eh, whatever, it works for now..." attitude towards wiring.I have a degree involving electronics, I'm not stupid. And I can tell how hot it is by touching it, so I know if it will do. Your wiring should (if it's halfway competent wiring) be labeled with wire gauge, either in AWG, or in cross sectional area, and it should also be labeled with the insulation temperature rating.If I still had the reel. The lowest temperature wiring insulation in common use is 60C/140F ratedThat stuff shouldn't exist. At my last place of work, the librarian had a desk fan with the flex touching the central heating radiator. It melted. If it can't stand the temperature of hot water.... "Adding more when there's a problem" isn't a replacement for a properly designed system, as by the time you notice it's hot, you've likely already gotten things hot enough to start causing thermal damage and further oxidation.Not if I check it regularly and don't allow it to be warm. 8A continuous, or intermittent?It's heating, it depends on the weather it can be on for extended periods. Typically, in electrical rating for wiring, there's a different rating for "continuous" (>3 hour) loads vs intermittent loads, and at least in the US National Electric Code, an 80% derating applies for continuous loads. So 90C 12AWG is rated for 30A, but for continuous loads, it's only suitable to 24A. This handles thermal mass and inertia in wiring - running a blender for 5 minutes is going to heat up wiring less than a heater, solar backfeed, EV charger, hot tub heater, etc.Too much complicated stuff to look up, easier to use the suck it and see method used by programmers, which is why Boinc messes up all the time, and why Windows has updates every 5 minutes. This is why wire also generally isn't rated for "amps"It could be, they should rate it for amps with a note saying reduce by x% if under insulation, etc. Just like my extension reel says "13A except if not fully unwound, then 7.5 amps". Nice and simple to understand. But at least there's an ocean between your place and mine.You worry too much, take a pill. |
Send message Joined: 9 Oct 20 Posts: 690 Credit: 4,391,754 RAC: 6,918 |
What defines someone as a narcissist?Who are you directing this at? |
Send message Joined: 5 Jun 09 Posts: 86 Credit: 3,394,368 RAC: 5,073 |
Wiring up high loads with "cables laying around," where you don't know the wire gauge, haven't calculated loads, etc, is the sort of "casually sloppy with high power things" I'm criticizing you for I hope you also undertook the oh-so-bring task of counting the number of cores as well. (It's not too bad when there are only 7 cores, but did I get to 37 or 39 before Fred shoved a cuppa under ones nose?)
All compliant (stranded) with current standards cable, above about 1mm^2, is required to have the conductor cross section, and insulation class (which may include the type of insulation), printed on the cable at regular intervals. Thus the cable you are suing does not comply with current regulations, or is rather old, and may, or may not, be compliant. There's a lot of non-complaint cable coming in from the far east (India & China being the main sources).
...and then there are "Arctic grade" cables, which extend the range down to -20C (ore even lower!), which is quite useful if you want to use the cable outside when normal people want to stay inside hugging the heaters.... Some of us are short of money and make do. Al wire is a hell of a lot cheaper. Most of us could reasonably claim to be short of money, but most of us do use the "right stuff". It's cheaper for good reasons - not the least of which being that without the appropriate markings it is automatically non-compliant with current standards. |
Send message Joined: 9 Oct 20 Posts: 690 Credit: 4,391,754 RAC: 6,918 |
I hope you also undertook the oh-so-bring task of counting the number of cores as well. (It's not too bad when there are only 7 cores, but did I get to 37 or 39 before Fred shoved a cuppa under ones nose?)It's stranded, I'm not counting those, why would that matter, I just twisted them up hard and measured the total. All compliant (stranded) with current standards cable, above about 1mm^2, is required to have the conductor cross section, and insulation class (which may include the type of insulation), printed on the cable at regular intervals. Thus the cable you are suing does not comply with current regulations, or is rather old, and may, or may not, be compliant. There's a lot of non-complaint cable coming in from the far east (India & China being the main sources).I either didn't look or it was a very short piece, I did say interconnects. ...and then there are "Arctic grade" cables, which extend the range down to -20C (ore even lower!), which is quite useful if you want to use the cable outside when normal people want to stay inside hugging the heaters....Won't they all go under 0C? People put wires outside all the time. My mother keeps her mower and extension cords in the garage and it gets to -10C there. They just go a bit stiffer. Most of us could reasonably claim to be short of money, but most of us do use the "right stuff".Then you're not that short of money. It's cheaper for good reasons - not the least of which being that without the appropriate markings it is automatically non-compliant with current standards.I don't care for standards, which is why I voted brexit. P.S. to horrify you even further I just snipped the wire on my new car coming out of the seatbelt socket. That foiled the health and softy system pretty easily. It thinks I have the belt on at all times. The bonging noise every 2 seconds for a few minutes is damn dangerous as it's very distracting while driving. |
Send message Joined: 5 Jun 09 Posts: 86 Credit: 3,394,368 RAC: 5,073 |
It's stranded, I'm not counting those, why would that matter, I just twisted them up hard and measured the total. This single statement clearly demonstrates your total lack of understanding of cable construction. Twisting cables in the manner you describe does not totally remove the packing space between the cores so the actual CSA of the metal is always less than that which you've guessed at. You are lazy, arrogant and stupid - clearly demonstrated by your disabling the "not wearing your seat belt" alarm when driving - don't forget it's an offence which costs you money when caught. Boasting about such acts does eventually end you up in court. P.S. to horrify you even further I just snipped the wire on my new car coming out of the seatbelt socket. That foiled the health and softy system pretty easily. It thinks I have the belt on at all times. The bonging noise every 2 seconds for a few minutes is damn dangerous as it's very distracting while driving. |
![]() Send message Joined: 15 May 09 Posts: 4444 Credit: 17,929,339 RAC: 29,974 |
Won't they all go under 0C? People put wires outside all the time. My mother keeps her mower and extension cords in the garage and it gets to -10C there. They just go a bit stiffer.Insulation not rated for the lower temperatures will likely get brittle. Norway and Finland often get -40C. When in the forces I saw insulation intended for warmer climes break. Some might be fine but just not been tested for lower temps but some not rated will almost certainly be dangerous. |
Send message Joined: 9 Oct 20 Posts: 690 Credit: 4,391,754 RAC: 6,918 |
And yet it agrees with what's printed on the cable.It's stranded, I'm not counting those, why would that matter, I just twisted them up hard and measured the total.This single statement clearly demonstrates your total lack of understanding of cable construction. Twisting cables in the manner you describe does not totally remove the packing space between the cores so the actual CSA of the metal is always less than that which you've guessed at. You are lazy, arrogant and stupid - clearly demonstrated by your disabling the "not wearing your seat belt" alarm when driving - don't forget it's an offence which costs you money when caught. Boasting about such acts does eventually end you up in court.Since I've not had an accident since 1997 which would require a seatbelt, the chances of needing one are far less than the bother of wearing one. Why are you incapable of assessing risks sensibly instead of seeing every risk as the end of the world? And it's very easy to pull it across you when the bacon is coming. Even if that fails, it's only £100, which is worth it for the extra comfort of not being into BDSM for every journey. |
Send message Joined: 9 Oct 20 Posts: 690 Credit: 4,391,754 RAC: 6,918 |
Probably only applies to non-UK temperatures, and I'd imagine all cable sold in Norway would be ok. And it's hardly dangerous, someone might get a shock or a fuse might blow, not the end of the world. And for those with the nanny state earth leakage breakers, it's very difficult to get a shock.Won't they all go under 0C? People put wires outside all the time. My mother keeps her mower and extension cords in the garage and it gets to -10C there. They just go a bit stiffer.Insulation not rated for the lower temperatures will likely get brittle. Norway and Finland often get -40C. When in the forces I saw insulation intended for warmer climes break. Some might be fine but just not been tested for lower temps but some not rated will almost certainly be dangerous. |
Send message Joined: 7 Sep 16 Posts: 262 Credit: 33,830,074 RAC: 23,996 |
Yeah it shouldn't and I don't know why, I just add more cable where there's a problem. If the problem is that your wiring is undersized for the job and the bulk of the wire is getting hot, this will work. If the problem, as you seem to imply, is your connections getting hot, you've got a bad crimp job, an improper connector for the job, or the wrong sized connector for your wire gauge (connectors have a rating for what wire gauges they're designed to work with, though there I go, nerding out about complex arcane specifications like "8-14 AWG" and such). You can probably cobble around it with more wire and connectors, but if you're not fixing the root problem, it's a rather cost-inefficient way of solving the issue (throwing wire wire at a connection termination problem).
What sort of "hell of a lot cheaper" prices are you seeing on it where you obtain the stuff? I know it used to be the case, but I just went poking around the site I usually order a lot of my wiring from, and 8AWG copper and 6AWG aluminum are almost the same price - 6AWG THHN-2 Al is $0.52/ft, 8AWG copper is $0.56/ft. I can't even find smaller aluminum wire anymore. Both of these are good for a 50A circuit under mostly standard conditions.
It's marginally cheaper, and if it's a "run it once and be done" sort of situation, the differences don't really matter. I tend to use the stranded stuff, though - as you note, it's a bit easier to work with. I don't mind working with solid wire, though. The house is wired up with 12AWG solid copper, and it's fine. I'm pretty sure I used stranded for the solar runs. Solid is a bit easier to work with for some terminations, though. I have a degree involving electronics, I'm not stupid. Then I have zero idea why you object to doing something like "looking up some wire ampacity charts and figuring out the proper wire gauge for your actual needs." Design it right from the start, and you don't have to go around "touching wire to see if it's too hot."
I was asking if your wire which you claim is 8A rated was rated assuming continuous or intermittent loads. Heating is by definition a continuous load, for any hard wired heaters. I would generally assume your wire was labeled for intermittent loads (which would be a bigger number for a given wire gauge), so at least with US NEC deratings, that would only be good for 6.4A continuous, and you'd need 4 of them in parallel for your 20A heater load (though 3 would probably be suitable too, just on the edge - but, again, I don't trust wire labeling like that, I do the math based on wire gauge, temperature, conduit packing, etc).
You claim an electronics related degree, and it's "too much complicated stuff" to look up a wire ampacity chart at the suitable temperature for your systems?
And also generally useless in designing anything more complicated than an extension cord. Wire gauge, insulation temperature rating, and the rest of the factors flow into some pretty simple charts and calculation factors based on what you want to do - if you've got more wires in a conduit carrying current, they're each derated somewhat because of total conduit heat dissipation issues, if they're being used in a high temperature environment, they derate as there's less overhead between ambient and the insulation rating temperature, etc. It doesn't take a licensed professional engineer to add a branch circuit to a house. It just requires a willingness to look up ratings in a few tables, and apply some basic percentage math beyond that. Probably only applies to non-UK temperatures, and I'd imagine all cable sold in Norway would be ok. And it's hardly dangerous, someone might get a shock or a fuse might blow, not the end of the world. And for those with the nanny state earth leakage breakers, it's very difficult to get a shock. You seem oddly resistant to the concept that electrical faults are a major cause of building fires that very much do kill people. Cracked insulation from lower than designed temperatures is a genuine hazard - and even if it doesn't arc, it's still allowing water and other things in to corrode sections of wire that are impossible to inspect, because they're in the center of segments of conduit, walls, etc. |
Send message Joined: 9 Oct 20 Posts: 690 Credit: 4,391,754 RAC: 6,918 |
If the problem is that your wiring is undersized for the job and the bulk of the wire is getting hot, this will work. If the problem, as you seem to imply, is your connections getting hot, you've got a bad crimp job, an improper connector for the job, or the wrong sized connector for your wire gauge (connectors have a rating for what wire gauges they're designed to work with, though there I go, nerding out about complex arcane specifications like "8-14 AWG" and such). You can probably cobble around it with more wire and connectors, but if you're not fixing the root problem, it's a rather cost-inefficient way of solving the issue (throwing wire wire at a connection termination problem).In general a warm wire happens and I add more wire. In this case it's the connection, I added a second one in parallel. What sort of "hell of a lot cheaper" prices are you seeing on it where you obtain the stuff? I know it used to be the case, but I just went poking around the site I usually order a lot of my wiring from, and 8AWG copper and 6AWG aluminum are almost the same price - 6AWG THHN-2 Al is $0.52/ft, 8AWG copper is $0.56/ft. I can't even find smaller aluminum wire anymore. Both of these are good for a 50A circuit under mostly standard conditions.Probably jsut got lucky, I found a company selling Al wire (actually CCA) for a quarter of the price of anyone's Cu. They don't sell Cu. It's marginally cheaper, and if it's a "run it once and be done" sort of situation, the differences don't really matter.It's a bugger to fit. Doesn't bend into tight spaces, like inside outlets. I tend to use the stranded stuff, though - as you note, it's a bit easier to work with. I don't mind working with solid wire, though. The house is wired up with 12AWG solid copper, and it's fine.I find they can come out, or snap the connection on the back of the outlet if there's any movement, like pulling it out to fit another. I'm pretty sure I used stranded for the solar runs. Solid is a bit easier to work with for some terminations, though.I disagree, solid can miss the screw altogether, with stranded something will grab. Then I have zero idea why you object to doing something like "looking up some wire ampacity charts and figuring out the proper wire gauge for your actual needs." Design it right from the start, and you don't have to go around "touching wire to see if it's too hot."Time is a limited resource. I was asking if your wire which you claim is 8A rated was rated assuming continuous or intermittent loads.No idea, I was going by ampacity charts per gauge. It's only a rough estimate anyway as there are so many variables. Heating is by definition a continuous load, for any hard wired heaters.Nonsense. If you have a 5kW heater and only 2.5kW is needed to keep the room warm, it will cycle on/off at 50% duty cycle. And also generally useless in designing anything more complicated than an extension cord. Wire gauge, insulation temperature rating, and the rest of the factors flow into some pretty simple charts and calculation factors based on what you want to do - if you've got more wires in a conduit carrying current, they're each derated somewhat because of total conduit heat dissipation issues, if they're being used in a high temperature environment, they derate as there's less overhead between ambient and the insulation rating temperature, etc.All you need is "This is 20A wire. Deduct 20% if under insulation, deduct x% for this, y% for that." You seem oddly resistant to the concept that electrical faults are a major cause of building fires that very much do kill people. Cracked insulation from lower than designed temperatures is a genuine hazard - and even if it doesn't arc, it's still allowing water and other things in to corrode sections of wire that are impossible to inspect, because they're in the center of segments of conduit, walls, etc.What percentage of people die in a building fire? Probably a billion times less than a car accident or cancer. You sound like the UK government, concentrating on the wrong things. |
Send message Joined: 7 Sep 16 Posts: 262 Credit: 33,830,074 RAC: 23,996 |
I disagree, solid can miss the screw altogether, with stranded something will grab. "Not working at all" is a better outcome than "Being partially connected, yet not having the full wire size connected." The first is easy to troubleshoot. The second works, until it overheats the few strands that are connected and causes problems.
I agree, that's why I do it properly the first time, instead of constantly having to go back and check to see if I screwed up.
Fine, and entirely irrelevant. The wiring still has to handle the full rated draw, safely, for extended periods of time. The general design of wiring and circuit protection, per what I'm familiar with, is that any wire must be rated to handle the full current the upstream protection device can provide - so if you have a 20A circuit breaker, the wiring had better be able to handle 20A indefinitely. The continuous load derating factors in here too.
As clearly stated in the various charts and correction factors you refuse to consider. "12AWG Copper 90C XHHW-2" is sufficient to answer all those questions. You're just insisting on your right to not have to bother.
US fire deaths are about 3800/yr, automotive fatalities are around 38,000/yr, give or take on both numbers. So, 10x difference, a couple orders of magnitude less than your guess. And a good reason that the fire deaths are fairly low is things like the NEC, that dictates wiring standards in a fairly conservative manner, vs "Do whatever you want and hope it doesn't catch fire." |
Send message Joined: 9 Oct 20 Posts: 690 Credit: 4,391,754 RAC: 6,918 |
But those strands are only mm until they touch the rest. Resistance is also proportional to length.I disagree, solid can miss the screw altogether, with stranded something will grab."Not working at all" is a better outcome than "Being partially connected, yet not having the full wire size connected." The first is easy to troubleshoot. The second works, until it overheats the few strands that are connected and causes problems. But doing it properly takes a lot more time and money than a quick check and alteration if required. Most time the guess was correct anyway. If in doubt just use more than you think you'll need, it future proofs it.Time is a limited resource.I agree, that's why I do it properly the first time, instead of constantly having to go back and check to see if I screwed up. Only if you know it will ever be used in such a way.Nonsense. If you have a 5kW heater and only 2.5kW is needed to keep the room warm, it will cycle on/off at 50% duty cycle.Fine, and entirely irrelevant. The wiring still has to handle the full rated draw, safely, for extended periods of time. The general design of wiring and circuit protection, per what I'm familiar with, is that any wire must be rated to handle the full current the upstream protection device can provide - so if you have a 20A circuit breaker, the wiring had better be able to handle 20A indefinitely. The continuous load derating factors in here too.In the UK they have some stupid thing in the regs (not sure why you call it a code, it's not a puzzle to solve) saying it's ok to have a double outlet which can take 20A total, even though it's a pair of 13A sockets. They claim it's unlikely someone would ever use both fully. Why not write it on the cable reel? Suitable for x A in this case, y in this case and z in this case.All you need is "This is 20A wire. Deduct 20% if under insulation, deduct x% for this, y% for that."As clearly stated in the various charts and correction factors you refuse to consider. "12AWG Copper 90C XHHW-2" is sufficient to answer all those questions. You're just insisting on your right to not have to bother. And there's no point in a table for all wire, as all wire is different. If I try to look up such a table, I find several different answers to the same question! I never said it was accurate, I just said it would be vastly more, which it is, so all efforts should only be on cars. No point in helping the eleventh who die in fires.What percentage of people die in a building fire? Probably a billion times less than a car accident or cancer. You sound like the UK government, concentrating on the wrong things.US fire deaths are about 3800/yr, automotive fatalities are around 38,000/yr, give or take on both numbers. So, 10x difference, a couple orders of magnitude less than your guess. And a good reason that the fire deaths are fairly low is things like the NEC, that dictates wiring standards in a fairly conservative manner, vs "Do whatever you want and hope it doesn't catch fire."Which only hurts those who choose not to be safe. |
![]() Send message Joined: 15 May 09 Posts: 4444 Credit: 17,929,339 RAC: 29,974 |
Added a battery to our grid tied solar 4 weeks ago. Since then, all crunching has been free. (Well we still have to pay the standing charge but that is all despite also charging the car on free electricity.) |
Send message Joined: 29 Oct 17 Posts: 944 Credit: 15,193,000 RAC: 23,306 |
With all my kit on running boinc tasks it uses 1.2kW, which can drain the batteries pretty quick if I run overnight. So I'm just a daytime volunteer. :) --- CPDN Visiting Scientist |
![]() Send message Joined: 15 May 09 Posts: 4444 Credit: 17,929,339 RAC: 29,974 |
With all my kit on running boinc tasks it uses 1.2kW, which can drain the batteries pretty quick if I run overnight. So I'm just a daytime volunteer. :)I cut down on the number of cores crunching at night. When it comes to winter I will be charging the battery at night using the 8p/KWH EV tariff so will probably run more cores at night than during the day. |
Send message Joined: 6 Aug 04 Posts: 192 Credit: 27,607,784 RAC: 8,472 |
With all my kit on running boinc tasks it uses 1.2kW, which can drain the batteries pretty quick if I run overnight. So I'm just a daytime volunteer. :)Six months Solar PV in 2024 (7kW array, WSW facing) has produced over 3 MWh, slightly less than our 2023 consumption for home and two EVs over the same six months. We switched energy supplier to an overnight/day leccy tariff and an export tariff. Excess Solar leccy (55%) is exported during the day. The battery and EVs charge overnight from 11:30pm. The battery powers everything from 5:30am until the Solar PV kicks in, and in the evening until the overnight rate starts. Since switching energy supplier, five months of leccy (including the standing charge) is MINUS £67. |
![]() Send message Joined: 15 May 09 Posts: 4444 Credit: 17,929,339 RAC: 29,974 |
Since switching energy supplier, five months of leccy (including the standing charge) is MINUS £67.Nice. Ours would be negative by about 400 a year if you count the payments we get for Feed in Tariff which we keep getting on the older panels on East facing side of the house for another 12 years. |
Send message Joined: 6 Aug 04 Posts: 192 Credit: 27,607,784 RAC: 8,472 |
Ours would be negative by about 400 a year if you count the payments we get for Feed in Tariff which we keep getting on the older panels on East facing side of the house for another 12 years.That's a good long-term ££ return from the FIT. |
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