a/c DC question

erne
erne Solar Expert Posts: 41
I have been installing a solar repeater site for an EMS system and my helper is the assistant chief of said firm. He is an X-navy nuclear electrical technician. During the installation progress he informed me that he also taught new technicians. One of the questions he asked these new students was if they knew how to tell if the problem could be diagnosed by the magic smoke from the circuit board or wire, whether it was on the “a/c” or “DC” side. This was a new diagnostic tool that I had never heard of, and I have been in this industry for many years. I thought maybe I should pass this tip by those of you that are wiser than I. He climes that DC smoke rises in a straight line, while a/c smoke is wavy because of the cycles it runs on. Can any of you verify this as a viable diagnostic tool.

Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: a/c DC question

    erne,
    where the smoke comes from can give a rough indication of where the problem is sometimes just as burn marks on parts and pc boards could. as to straight and wavy smoke for dc and ac respectively, he is pulling your leg.:p
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: a/c DC question

    a/c usually is short for air conditioner. I have never seen smoke rise from an a/c.

    Niel is quite correct about ac and dc smoke. --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • plongson
    plongson Solar Expert Posts: 115 ✭✭
    Re: a/c DC question

    Smoke has absolutely NO magical potencies, but, smoke is what drives all things electrical.

    Don't believe it? Have you ever seen anything run after the smoke escapes??
    3500w solar, 800AH with Rolls Surrette, Magnum inverter, Midnite charge controller, Kubota 21kW diesel genset...private well...and just recently connected to city power for additional options...nice to have options 
  • Thom
    Thom Solar Expert Posts: 196 ✭✭✭
    Re: a/c DC question

    He will be sending you out for frequency grease next . :0)
    Well that's what I would do!

    Thom
    Off grid since 1984. 430w of panel, 300w suresine , 4 gc batteries 12v system, Rogue mpt3024 charge controller , air breeze windmill, Mikita 2400w generator . Added 2@ 100w panel with a midnight brat 
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: a/c DC question
    erne wrote: »
    I have been installing a solar repeater site for an EMS system and my helper is the assistant chief of said firm. He is an X-navy nuclear electrical technician. During the installation progress he informed me that he also taught new technicians. One of the questions he asked these new students was if they knew how to tell if the problem could be diagnosed by the magic smoke from the circuit board or wire, whether it was on the “a/c” or “DC” side. This was a new diagnostic tool that I had never heard of, and I have been in this industry for many years. I thought maybe I should pass this tip by those of you that are wiser than I. He climes that DC smoke rises in a straight line, while a/c smoke is wavy because of the cycles it runs on. Can any of you verify this as a viable diagnostic tool.

    Some time you should look up the story of the Windows utility program "nosmoke.com"
    SMA SB 3000, old BP panels.
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: a/c DC question
    Thom wrote: »
    He will be sending you out for frequency grease next . :0)
    Or a left handed monkey wrench, or a bucket of propwash... :D
  • erne
    erne Solar Expert Posts: 41
    Re: a/c DC question

    I have 2 quarts of frequency grease and bought his smoke return gun. boy I got to him I only had to pay $400 for it. I didn’t know that prop wash could be used in solar.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: a/c DC question

    erne,
    glad to see you have a sense of humor as the guys are really having a field day with this.

    you could go back to the guy and tell him you have a solution to the smoke, be it ac or dc, just by putting a drip loop near it to extinguish it before it appears all the while pointing to him.:p
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: a/c DC question
    erne wrote: »
    I have 2 quarts of frequency grease and bought his smoke return gun. boy I got to him I only had to pay $400 for it. I didn’t know that prop wash could be used in solar.

    Anybody can see that propwash is only used for wind power, not for solar. (OK, if you are building a solar-wind driven turbine maybe....)
    SMA SB 3000, old BP panels.
  • SolaRevolution
    SolaRevolution Solar Expert Posts: 410 ✭✭
    Re: a/c DC question

    Tell him a better diagnostic tool is to dunk the circuit boards into a bucket of steam and watch for condensation in the fallopian tubing.
  • fix_it_guy
    fix_it_guy Solar Expert Posts: 26
    Re: a/c DC question

    I guess technology has changed the jobsite pranks. What ever happened to sending the new guy to fetch the board stretcher. lol
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: a/c DC question
    fix_it_guy wrote: »
    I guess technology has changed the jobsite pranks. What ever happened to sending the new guy to fetch the board stretcher. lol
    I worked in the oil field for a while, and new guy hazing is pretty commonplace in that workplace. Once a new guy on a drilling rig was approached by a crusty old tool pusher, who told him to haul a huge crescent wrench up to the top of the derrick and tighten the large nuts that hold the support struts together. Actually, those nuts are torqued hydraulically to very high numbers when the derrick is assembled and there's no way they could come loose.

    The new guy wasn't as green as the TP thought, so when he went to the tool shack to get the wrench, he picked up a couple of spare nuts, which he took with him up to the top of the derrick. He was up there for a while, and when he came back down he told the TP that all the nuts were tight except for these two he found lying around up there, but he couldn't see where they came from. The guys on the rig said they didn't realize that old TP could climb a derrick that fast. :D
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: a/c DC question

    i like that story ggunn.