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Thermostat wire

Snowmelt
Snowmelt Member Posts: 1,405
Does two wire thermostat wire come stranded at all or is it all hard wire?

Comments

  • SWEI
    SWEI Member Posts: 7,356
    Yes, but

    it probably won't be labeled as thermostat wire.  Try looking for 18/2 jacketed low voltage control wire.  You should be able to cross this to other manufacturers:  Connect-Air W181P-2051
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,239
    Another little tid-bit of interest.

    If you are running AC current, both solid and stranded wire will suffice. However if you are running DC current it is a good idea to stick with stranded wire.



    Harvey
  • ChrisJ
    ChrisJ Member Posts: 15,589
    edited April 2014
    AC vs DC?

    Harvey,



    This is the first time I am hearing such a thing and I work in the electronics industry.  What would be the reason for sticking with stranded for DC?  The only thing that I can think of that might ever matter is the skin effect which only happens with AC and is practically meaningless at 60Hz.



    To the OP, I ran 4 conductor stranded 18AWG to my stat.  I had originally used 2 conductor but wanted a common to power the stat so swapped it out for 4 conductor.  I'd highly recommend running more than two because you never know what you might want down the road.  As others have said just look for some 18AWG stranded wire of whatever multiple in a single jacket.  I think the brand I used was Belden and has red, white, green, black.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Techman
    Techman Member Posts: 2,144
    solid vs stranded

    My understanding of it , the stranded wirers have more total surface area, and that helps conduct the dc/electronics better
  • Gordy
    Gordy Member Posts: 9,546
    Surface area of stranded

    Like techman said.
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,239
    Ditto Techman, Gordy

    That what I was taught as well.



    Chris, I have nothing but respect for your electrical knowledge. I know you are much better versed on the subject then I am. I have no explanation other then, that is what I was taught. I won't be offended in the least if I'm I'm wrong on this.



    Harvey
  • ChrisJ
    ChrisJ Member Posts: 15,589
    Suface area

    As far as I am aware, stranded vs solid only ever matters in regards to AC and never DC. With AC the skin-effect is fairly deep at 60Hz so it would only matter when dealing with fairly large conductors, something like 8mm diameter if I recall.





    Here's a wiki on it.

    http://en.wikipedia.org/wiki/Skin_effect





    Harvey, I'm sorry if we have had this discussion before, based on your response I'm concerned we may have. If we did, I completely don't remember and didn't mean to offend you.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,239
    No man.

    Never this one. I just knew you were pretty heavily involved in electronics from comments throughout the years. I enjoy learning from you. This site is really great! I learn something from someone every day :-)



    Harvey
  • SWEI
    SWEI Member Posts: 7,356
    DC has greater arc potential

    which is why you see lower current ratings on switches, circuit breakers, and relays.  At these frequencies, AC and DC have essentially identical behavior in wires.
  • Techman
    Techman Member Posts: 2,144
    edited April 2014
    st. vs so

    I read that wiki download and groaned in pain thinking of those formulas. A wrench anyone! LOL. Was that article geared towards hi volt and hi amps? In the DC/electronics control circuits there is real lo amps,so is it the "intensity" of the volts? Carrier's VVT control system class (and they did Disney in Fl ) said to use stranded wire, Daikin, Fujitsu, Sanyo and others say to use stranded wire.



    Chris J good pictures!!
  • ChrisJ
    ChrisJ Member Posts: 15,589
    edited April 2014
    Frequency and material

    Hi Techman,



    As far as I am aware only frequency and material of the conductor have an effect on it. In DC circuits where I work we typically use solid wire even when dealing with micro and millivolts.





    Thank you in regards to the pictures. I try to keep updating them as things change.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Tim McElwain
    Tim McElwain Member Posts: 4,612
    It has been my experience

    especially in dealing with Powerpile self generating systems using millivolts that solid wire tends to be the better way to go, especially when having to twist two wires together (splice) and then solder. I never really took precise measurements but it always seemed that stranded wire on millivolt (DC) just offered more resistance there fore a greater millivolt drop across connections.



    On AC my understanding of skin effect is due to opposing currents as related to the magnetic field created around the wire. So more likely a problem with wire selection on AC