Let's make a HUGE Resistor (High Power)

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  • เผยแพร่เมื่อ 22 พ.ค. 2024
  • High quality PCB prototypes: www.pcbway.com
    🔥How to make your own high power resistor using nichrome wire and other cheap parts! Check it out!
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ความคิดเห็น • 109

  • @antibrevity
    @antibrevity 10 วันที่ผ่านมา +29

    3:27. The green power resistor shown here is *not* looped back to the start to reduce inductance. You can see that the end of both strands terminate at the band at each end of the tube and those bands serve as the terminals that hook into the circuit to provide some degree of voltage separation in high-power circuits. These strands are in parallel to reduce per-strand current. However, it is a good idea to use a bi-directional loop to reduce inductance.

    • @JeremyAkersInAustin
      @JeremyAkersInAustin 10 วันที่ผ่านมา +3

      Came here to say the same thing... Not sure where he got the idea that it was looped back?

    • @sdjhgfkshfswdfhskljh3360
      @sdjhgfkshfswdfhskljh3360 10 วันที่ผ่านมา +2

      It is sad to have misinformation in educational videos.

    • @Thingstest-rl8xu
      @Thingstest-rl8xu 10 วันที่ผ่านมา

      Yes, most commercial power resistors are not make to control Inductance. Even then Reduce Inductance is likely not going to do anything for the application.

  • @matthewf1979
    @matthewf1979 9 วันที่ผ่านมา +10

    Electric hot water heater coils make fantastic high power resistors. They're around 8 to 10 ohms and can handle 3kw+. Super inexpensive too, around $20usd.

  • @nonsquid
    @nonsquid 11 วันที่ผ่านมา +28

    Another way to make a temporary high power resistor is to get a 5 gallon bucket. Fill the bucket with salt water and use to copper pipes as electrodes. You can change the resistance with dilution. This is used for battery bank test discharge loads.

    • @SpecialeW
      @SpecialeW 10 วันที่ผ่านมา +4

      And electrolyse the water and generate hydrogen?
      Sounds like a blast

    • @mosta5
      @mosta5 10 วันที่ผ่านมา +3

      That wouldn't be an ohmic resistor meaning that it doesn't follow ohm's law and V doesn't always equal IR in it so it will not be suitable for the calculations

    • @EdwardTriesToScience
      @EdwardTriesToScience 10 วันที่ผ่านมา

      baking soda is better (potassium hydroxide even moreso) as it wont generate chlorine and poison you, saltwater is fine for AC not DC

    • @klave8511
      @klave8511 9 วันที่ผ่านมา +4

      Better to use NaOH, no chlorine

  • @peterdkay
    @peterdkay 10 วันที่ผ่านมา +13

    I made a 1kw resistor load for my wind turbine made from galvanised steel wire wound onto a house brick. Worked well.

    • @Jefferson-ly5qe
      @Jefferson-ly5qe 2 วันที่ผ่านมา +1

      Anyone repeating this should make sure not to breath in the funes. Zinc fever sucks

    • @peterdkay
      @peterdkay วันที่ผ่านมา

      @@Jefferson-ly5qe Did not realize that!! Fortunately my resistor only dissipated about 300W so only warmed the brick. Original galvanizing is still there. After 3 years i found domestic wind power was not viable and replaced it with 4.5kW solar which generated more power than I use,

    • @Jefferson-ly5qe
      @Jefferson-ly5qe วันที่ผ่านมา

      @@peterdkay yeah 300W sounds like it wasn't enough to cause issues but I suspect it would be if you put kW+ into it. Zinc fever is often encountered by welders who don't remove the zinc coating on galvanised steel before they start welding.
      Your experience with wind seems a common one. It's great rechnology nut doesn't work well at domestic scales.

  • @chrishuhn5065
    @chrishuhn5065 11 วันที่ผ่านมา +9

    Why did you use cloth tape instead of polyimide (Kapton) tape? Kapton is heat resistent up to 400°C and there's no vibrations or abrasion on a resistor, so mechanical stress isn't a problem.

  • @juansebastianraigozatabord3625
    @juansebastianraigozatabord3625 11 วันที่ผ่านมา +6

    wow!!! I didnt know you speak spanish as well, I just checked your spanish version channel and its awesome, you know a lot, I really admire you, saludos desde Colombia!!

    • @ELECTRONOOBS
      @ELECTRONOOBS  11 วันที่ผ่านมา

      :) gracias!!!

    • @jamess1787
      @jamess1787 10 วันที่ผ่านมา +1

      He's a Spaniard, pretty sure. 🤔

    • @Vic-sp6ld
      @Vic-sp6ld 8 วันที่ผ่านมา

      @@jamess1787 He is. I mean, his accent makes it clear.

  • @klave8511
    @klave8511 9 วันที่ผ่านมา +2

    I used to use incandescent light bulbs, needs lots of light bulb fittings but you can mix and match for the power you need. For low voltage I used car light bulbs. You can see when power is on. Sounds cheap but costs add up when you need a lot.

  • @Guishan_Lingyou
    @Guishan_Lingyou 11 วันที่ผ่านมา +5

    Glass can handle high heat, but not rapid changes in temperature. If you wrap nichrome wire around it and that wire heats up quickly, the glass might crack or even shatter.

    • @paradiselost9946
      @paradiselost9946 8 วันที่ผ่านมา

      quartz glass... cough cough... "radiant bar heaters"...

  • @mvrkmi
    @mvrkmi 10 วันที่ผ่านมา

    Excellent explanation! I used nichrome wire to make a coffee cup warmer. The store-bought ones were either too expensive and/or didn't maintain a coffee temperature I prefer. It works great, and in this case, the heat generated by the nichrome wire is "a feature, not a bug." ;-)

  • @junglerider007
    @junglerider007 12 ชั่วโมงที่ผ่านมา

    Clay pottery handles temperatures of about 1,000 degrees F (the beginning of glowing red heat - about 540 C). Traditional, tribal earthenware is fired to about 1,400 degrees F (760 C),so you get clay water bottles,,on which nicrome wire can be coiled around.

  • @Felipe2077tv
    @Felipe2077tv 11 วันที่ผ่านมา +4

    There's quite a few flaws that were overlooked in this project, that would have been alleviated by going with the plaster/cement/terracota/ceramic option
    - That radiator is unlikely to dissipate 300w of heat from the resistor
    - The cloth can become a fire hazard due to the heat and/or melt
    - Many leak points (which you mentioned) around electronics (bad)
    - The watercooled vision is very large/unwieldy vs the passively cooled resistor
    - Higher cost
    - Requires seperate power supply for the pump + fan

    • @ELECTRONOOBS
      @ELECTRONOOBS  11 วันที่ผ่านมา +2

      That's right! Thanks for all the tips!

    • @NiHaoMike64
      @NiHaoMike64 11 วันที่ผ่านมา +1

      Could try using a water heater element if it would be of suitable resistance. Simplest would probably be a heat resistant frame to wind a mesh onto with a fan for cooling.

  • @izzzzzz6
    @izzzzzz6 8 วันที่ผ่านมา

    You could also submerge the entire thing in a big bucket of distilled water but use ceramic, glass or stainless. For ceramic solutions you could pick up unwanted pottery such as floor vases or larg glass piece from your local 2nd hand store.

  • @ranganatennakoon
    @ranganatennakoon 9 วันที่ผ่านมา

    very good explain,
    Even if you apply oil on the PVC pipe, it comes off very easily
    thanks !

  • @barrymayson2492
    @barrymayson2492 7 วันที่ผ่านมา

    I had a wind turbine and its resistor was a thick wire about 5mm thick. And to stop the turbine when working on it the resistance was a solid bar of aluminum shorted across the terminals

  • @j1952d
    @j1952d 11 วันที่ผ่านมา

    Way back when we needed a load for low voltage and high power, we used to sink a 1kW electric "bar fire" element in a bucket of water, Using R = V*V/P, the resistance was about 53R (UK, so 230Vac).

  • @gf2e
    @gf2e 10 วันที่ผ่านมา

    I was just thinking about this yesterday. Great timing :)
    One silly idea I had was to run the wire inside a block of frozen distilled water. One kg would absorb 100 Wh as it melted. And then another 100 Wh getting to 80C. For short term tests, that might work well.
    (My particular use case is testing out USB C car chargers. They tend to overheat quickly at high loads. So 100 Wh would probably make most of them melt their plastic before the ice all melted…)

  • @mbunds
    @mbunds 10 วันที่ผ่านมา

    I love this channel!

  • @JohnDuthie
    @JohnDuthie 11 วันที่ผ่านมา

    ayy youtube's recommending you again. I had to search you up last time I watched. But, today, it's in on the home page.

  • @mysticMiner
    @mysticMiner 11 วันที่ผ่านมา +2

    Copper ist actually diamagnetic since its permeability ist lower than 1. Seems Like a pretty OK choice to me. 😊
    Eddy currents are another topic, but since the magnetic Flux density inside the pipe should be quite low and you dont want to use it as a high power AC load, the effect should be negligible.
    Nice projekt overall 😊
    (please forgive language errors, im Not a native english speaker)

  • @joshadsett4835
    @joshadsett4835 10 วันที่ผ่านมา

    I am liking the project

  • @mosta5
    @mosta5 10 วันที่ผ่านมา

    You could use an electric furnace as your resistor for the wind turbine it's already nichrome wire and you can use it for heating food in windy days and even better you can use something called Phase changing Materials which is like a thermal battery that stores heat so you basically get extra energy storage for your system but in another form

  • @barrymayson2492
    @barrymayson2492 7 วันที่ผ่านมา

    I made a pair of heated gloves from ni-cr wire. It worked well but only had on off switch so was some times getting hot.

  • @salahuddinbangash4785
    @salahuddinbangash4785 5 วันที่ผ่านมา

    Water + Electricity , nice combination 😂

  • @self_taught_stuff
    @self_taught_stuff 11 วันที่ผ่านมา

    you can use those thermal pads to wrap the copper pipe, that way you will isolate it and be able to transfer more heat from the wire to the pipe.

  • @leehewitt9559
    @leehewitt9559 11 วันที่ผ่านมา

    Interesting video 👌

  • @wizrom3046
    @wizrom3046 5 วันที่ผ่านมา

    Buy a bag of big old NPN power transistors, they are available very cheap now as they are obsolete technology.
    Big flat pack transistors are good for about 65w each if bolted to a big slab of metal.
    You can probably get 20 transistors for 20 dollars.
    That gives you an additional benefitmof being able to control them, ie ADJUSTABLE load

  • @jglenn78
    @jglenn78 5 วันที่ผ่านมา

    Apologies if this has been suggested before, but why don't you incorporate a TEG and use the excess heat from the resistor for extra power?

  • @donamills
    @donamills 10 วันที่ผ่านมา

    Not sure if you already tested this, but nichrome expands quite a bit.
    Be careful that it doesn't create its own short due to that fact.
    I know its water cooled but 3kw is a lot of heat to dissipate .

  • @chemarytech
    @chemarytech 6 วันที่ผ่านมา

    el threadlocker es para pegar 2 metales y evitar que se desenrosquen con el uso o las vibraciones, por ejemplo se usa en varios tornillos de una bici, pero no es indicado para pegar metal con teflon, quizas ni se endurezca, tampoco esta pensado para estar en contacto con el agua. Una opcion podria ser utilizar solo teflon, o usar una aleacion de estaño con un punto de fusion bajo y calentarlo muy rapido, tambien puedes sellarlo por fuera con cinta autosellable para fugas

  • @Yorumcu63
    @Yorumcu63 11 วันที่ผ่านมา

    Nice Video

  • @galileo_rs
    @galileo_rs 10 วันที่ผ่านมา

    Teflon tape (plumbers tape) as a high temperature insulator. For plaster find go to a hardware store and buy heatproof plaster , it is used for wood stoves, fire places, ovens and kilns.

  • @nickblacklock7526
    @nickblacklock7526 10 วันที่ผ่านมา

    An other useful device for this type of testing is a carbon pile, the type used for testing automotive batteries and charging systems. As you turn the dial it compresses the carbon disks and the resistance decreases. Basically a high current low ohm variable resistor.

  • @troublehd7236
    @troublehd7236 10 วันที่ผ่านมา

    nice video

  • @carlwest859
    @carlwest859 11 วันที่ผ่านมา

    May be use a ceramic floor tile for a support, stood on end with a fan for air cooling.

  • @-Evilempire-
    @-Evilempire- 11 วันที่ผ่านมา

    instead of grout for the tiles you have to use refractory cement with a little mesh inside.

  • @soumyaranjanmoharana4804
    @soumyaranjanmoharana4804 11 วันที่ผ่านมา

    One more thing there is a thing called fibre glass sleeves which can withstand very high temp so you can use that for insulating the nichrome wires.

    • @t1d100
      @t1d100 10 วันที่ผ่านมา

      These can be found at automotive parts stores. They are used to wrap exhaust pipes.

  • @y2ksw1
    @y2ksw1 6 วันที่ผ่านมา

    You also may use a heater which may easily dissipate 2-6 kW and also heat utility water. Besides of being dead cheap.

  • @WagonLoads
    @WagonLoads 10 วันที่ผ่านมา

    18:34 For the slider, just use a metal hose clamp.

  • @Kmnri
    @Kmnri 11 วันที่ผ่านมา +2

    Submerge it in mineral oil

  • @pieterboots8566
    @pieterboots8566 7 วันที่ผ่านมา

    You could use many small resistors in parallel.

  • @aycebenzsalud
    @aycebenzsalud 5 วันที่ผ่านมา

    What about just short the wind turbine if the battery is fully charged and the turbine is only outputting low voltage (when there's barely any wind) so it ends up being that the eddy currents resist and stop the turbine from spinning

  • @JoaoMoreira-mg4zj
    @JoaoMoreira-mg4zj 11 วันที่ผ่านมา

    u could have used expoxy or liquid plastic in an can to creat a layer of isolation betwen the pipe and the wires and made a second layer to to isolate from a second layer of nicrome wire

  • @daveluxton8317
    @daveluxton8317 5 วันที่ผ่านมา

    cool video (or hot ;) ) . Is there a link to that mega resistor? I have similar ones but smaller. I used plaster of paris mix with a little bit of fine sand. for my furnace. easy to find in store and simple to work with. Although it is not a strong as a real ceramic.

  • @AKG58Z
    @AKG58Z 11 วันที่ผ่านมา

    More on hoverboard motor generator project 👍👍👍

  • @MrAndrewAllen
    @MrAndrewAllen 9 วันที่ผ่านมา

    Winding resistor wire on glass can result in a hot wire cutting the glass.

  • @danblankenship5744
    @danblankenship5744 11 วันที่ผ่านมา

    I like this format. I enjoy watching you work out solutions on your way to a finished product.
    I would have tried fireplace bricks, but that will take up much more space.

  • @arturperreira5680
    @arturperreira5680 7 วันที่ผ่านมา

    Hello try laser cut steel from jlpcb make a nece add and a good variable resistor

  • @JohnDuthie
    @JohnDuthie 11 วันที่ผ่านมา

    Mixing metals isn't that going to cause a ton of corrosions?

  • @Orentas01
    @Orentas01 4 ชั่วโมงที่ผ่านมา

    That tape starts burning if that wire reaches 100c degrees

  • @barrymayson2492
    @barrymayson2492 7 วันที่ผ่านมา

    Another idea is to find an amateur potter and get them to make some tubes and fire them for you.

    • @ELECTRONOOBS
      @ELECTRONOOBS  7 วันที่ผ่านมา

      Or use a brick! Is only 50 cents :)

  • @Sir-Dexter
    @Sir-Dexter 22 ชั่วโมงที่ผ่านมา

    nice

  • @Eapancotech
    @Eapancotech 9 วันที่ผ่านมา +1

    So do we call it reostate

  • @soumyaranjanmoharana4804
    @soumyaranjanmoharana4804 11 วันที่ผ่านมา

    You forgot that cement without any reinforcement can't withstand compression force so it broke. What you could have done is put some kind of wires inside the mold as reinforcement and then fill the rest with cement mixture.

  • @andreadavid7868
    @andreadavid7868 10 วันที่ผ่านมา

    Why you just dont try using a beer/wine bottle filled with water? as you say glass is good electrical and thermal insulator, if you put some water inside you will increase the heat dissipation, i guess could be more easier. btw nice job!

  • @mubbashirshirazi3758
    @mubbashirshirazi3758 11 วันที่ผ่านมา

    sure copper is conductive but its not ferromagnetic so it wont increase magnetic fields

  • @RobinGerritsen1995
    @RobinGerritsen1995 3 วันที่ผ่านมา

    Or make the wind turbine able to rotate the fins to make it aerodynamic and it will not rotate anymore. This is how the big windturbines turn off.

  • @legominimovieproductions
    @legominimovieproductions 6 วันที่ผ่านมา

    I make high power resistors myself from nichrome wire for diy project XD its not so easy or cheap to get a multiple hundret watt rated resistor at less than a couple ohms

  • @kau_norw
    @kau_norw 11 วันที่ผ่านมา +1

    You can buy nichrom metal band, but it is not an easy task to bend a nichrom metal band at the high side allround a pipe, Assume it increases the cost of production.😬

    • @gf2e
      @gf2e 10 วันที่ผ่านมา +1

      I was thinking about that. I bet the corrugated shape on the commercial resistor is asymmetric. The right shape of crimp will make the metal band curve around the rod.

  • @Seumu990
    @Seumu990 11 วันที่ผ่านมา

    Why not use in copper pipe Compression Fitting? No heat, no special tools and easy to use 👍

  • @RdGear
    @RdGear 11 วันที่ผ่านมา +2

    You can use plaster of parish for molding.

  • @URBANKILLER.X
    @URBANKILLER.X 11 วันที่ผ่านมา +1

    Make virable resistor

  • @yakut9876
    @yakut9876 10 วันที่ผ่านมา

    can you add subtitles ? please.

  • @pastasauce99
    @pastasauce99 10 วันที่ผ่านมา +1

    Resistor: " I will not stop resisting"
    Cop: "Chill bro"

    • @ELECTRONOOBS
      @ELECTRONOOBS  10 วันที่ผ่านมา +1

      How is the CURRENT situation?

    • @roo1871
      @roo1871 9 วันที่ผ่านมา

      @@ELECTRONOOBS I'm AMPED up

  • @user-ik3pq4we9y
    @user-ik3pq4we9y 6 วันที่ผ่านมา +1

    אתה רעעעעעעעעע

  • @nowheremanjk8624
    @nowheremanjk8624 11 วันที่ผ่านมา

    Rezystory rozruchowe w lokomotywach prądu stałego to 2 szafy ;-}

  • @m4th1js
    @m4th1js 8 วันที่ผ่านมา

    you need kapton tape

  • @nowheremanjk8624
    @nowheremanjk8624 11 วันที่ผ่านมา +1

    A jeszcze zapytam o skórę, czy na tatuażu rezystancja jest inna? ;-}

  • @MegaFoster86
    @MegaFoster86 6 วันที่ผ่านมา

    23 and no tests 😢

  • @italogarcia1597
    @italogarcia1597 11 วันที่ผ่านมา

    Basta fazer uma placa de circuito impresso com padrões de trilhas densos de cobre e colocar uma ventoinha sobrez

  • @gervasotattico7070
    @gervasotattico7070 10 วันที่ผ่านมา +1

    Copper is diamagnetic, so no induction problems.

  • @t1d100
    @t1d100 10 วันที่ผ่านมา

    For the resistor body... Maybe the fireproof brick that is used to line fireplaces and furnaces. This special brick is creme colored, not brown, or red. It is available in the USA at the big-box hardware and lumber supply stores and, of course, brickyards. They come in different sizes and shapes. One the size of a typical brick should be easy to wrap the wire around. Also, the fireproof mortar maybe useful. The green manufactured resistor may have special wire that does not have so much thermal drift. I am thinking that you are going to have a challenge with the wire that you are using, because it probably has a large heat coefficient. This may make it unusable. My guess is that the wire on the commercially made unit has limited drift and that this is the reason that it is so expensive. You can also repurpose a cheap space heater. Just be sure to use all safety measures, no matter which path you take. Cheers!

  • @thevoidedwarranty
    @thevoidedwarranty 9 วันที่ผ่านมา

    How demonitise in 5 seconds :))

  • @xDR1TeK
    @xDR1TeK 7 วันที่ผ่านมา

    Plastic is not a megaohm conductor. Not even gigaohm. Please try again.

  • @Thingstest-rl8xu
    @Thingstest-rl8xu 10 วันที่ผ่านมา

    I like your channel but this is wrong in so many ways and likely result in a fire as Most plastics and cloth will melt or burn causing a short to the pipe. Nichrome will expand even before it glows and as it grows, spots can heat more then other areas and cause other problems as it heat cycles. Commercial power resistors have more things adding cost beside "not making enough units for the demands." Much harder to make them because of "Fire Proofing" etc to meet various Safety rules for a final product to Pass testing by TUV CE UL and related agencies.

  • @markmaker2488
    @markmaker2488 10 วันที่ผ่านมา

    If you’re running water through a pipe, consider using a plastic pipe with the coil inside rather than wrapping it externally.

  • @VEC7ORlt
    @VEC7ORlt 8 วันที่ผ่านมา

    That was painful to watch...
    First of all that insulating tape will burn to crisp when that 'resistor' gets any substantial amount of power.
    You could have used lightbulbs, water heater elements, just dunked that wire into a bucket of water, steel wire or tape.

  • @galihaimar6701
    @galihaimar6701 11 วันที่ผ่านมา

    amazing bro
    #first coment

  • @Service_John
    @Service_John 11 วันที่ผ่านมา

    2nd!

  • @noreenjitkaur8136
    @noreenjitkaur8136 11 วันที่ผ่านมา

    3rd

  • @whizatit
    @whizatit 9 วันที่ผ่านมา +1

    There is SOOOO much wrong with this video. PLEASE for the love of all man kind don't copy this!

    • @paradiselost9946
      @paradiselost9946 8 วันที่ผ่านมา

      power engineering is a whole new ball game that really throws the average hobbyist that deals with chips and fets and coding...
      if the goal is simply to brake it at high wind speeds... easier to just short the generator out.
      if the goal is to produce heat, then forget about batteries and concentrate on making heat. a method that is far more suited to wind power, and can take advantage of the cubic law of power to wind velocity. and provides braking. and doesnt have a limit due to batteries and their charging status...
      what to DO with the heat is the challenge...
      throw it away as a waste product? this society thrives on throwing things away...

    • @mikebond6328
      @mikebond6328 8 วันที่ผ่านมา

      I’m doing it.

  • @Murphydeffa-oq8lm
    @Murphydeffa-oq8lm 10 วันที่ผ่านมา

    this guy dont know what its talkinb about, "can withstand more head than copper, has more reistance than copper" lack of education. the REASON whi nichrome is used it has little resistance change compared to temperature, A.k: small temperature coeficent. Guy dont know and just makes up things as he goes.
    Kids look video, learn, go to get job, and will be kicked out because random mumble that wont make sense.

    • @ELECTRONOOBS
      @ELECTRONOOBS  10 วันที่ผ่านมา +1

      Chill bro, I might have expressed wrong something due to my English level. But all I'm saying is that copper has lower resistance so it allows electrical current to flow easily through it without much energy loss. This energy loss is what generates heat and in this case we need the wire to dissipate as much heat/cm so we could use it as a high power load without the need of hundreds of meters of wire. Also, as I mention, copper could withstand less heat, since it would melt at around 1000 degree but nichrome could go up top 1400 degrees.
      And yes, "can withstand more head than copper, has more reistance than copper", nichrome has a lot higher resistivity than copper

    • @paradiselost9946
      @paradiselost9946 8 วันที่ผ่านมา

      but nichrome is nowhere near as good as invar... or constantin, when it comes to thermal coefficients...
      so, why do we use tungsten for filaments instead of nichrome? whats the temp coefficient of tungsten?
      its irrelevant in that case. its all about its refractory properties, its ability to withstand heat without failure.
      could just as easily dump this power into copper or steel as an arc and melt the metal and use the arc gaps resistance rather than the metals resistance to liberate the heat... again, coefficient of temperature doesnt mean a thing...
      UNLESS the precise value of the resistor at any specific temperature is a critical value.

    • @Murphydeffa-oq8lm
      @Murphydeffa-oq8lm 7 วันที่ผ่านมา

      @@paradiselost9946 tunghsten is used for other reaosn, Main reason is high melting point. low resistance at room temp is main reason why bulbs burn out. If you limit current they last way longer. But you cant use nichrome because of low melting point.
      And yes there are better alloys for resistors, constantan is one of them. Nichrome has high melting point, it also forms protective layer and has relativly "taame" temperature/resistance curve.
      Copper on other hand is terrible as resistor. resistance will change wild with temperature, it will oxydize in air. And it has low melting temperature. If you use copper heating element it may draw like 100kW and when it heats up its 1kW. If head conduction is not uniform one section will heat first and will burn out. Thats why low change in resistance is important, power will be disapated uniformly across conductor.