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    PCB oil, what part contains it?

    Working on an old HP 330B Distortion Analyzer that I really want to fix up, but it has a PCB warning on the back...

    I'm guessing it's the 1uf 400v cap near the bottom center/right of the underside picture? Everything else looks like normal paper or electrolytic.

    I hope it's not the transformer, because there is something oily underneath it. It is noticeable on the wires coming out of the transformer, and on the power cord beneath.








    #2
    Re: PCB oil, what part contains it?

    Yup, that would be my assumption, having been around those transformers when servicing old TV & Radio equipment. They used an asphalt tar for insulation (potting) the windings, much the same as lamp ballasts. I still have a few of those beasts about.

    Also be suspicious of the metal can capacitors. The oil impregnated paper used in cap construction is the problem. Larger caps such as motor start/run caps are oil filled and since the 80's are required to say Non-PCB or such. Prior to then, look for words like Clorinol or Pyranol on the label.

    Seek information (Google) on the manufacturer of those metal caps as to PCB content.

    Assume the worst unless stated otherwise.

    Now the reality check - Are you going to be in contact with the leaking oil or in the event of a fire, the smoke and vapors? Is there enough of the material present in the equipment to cause you or anyone else harm? I grew up playing with that stuff at some point in the pesticides, riding bikes in the fog from mosquito control, playing in the train yards, and watching this magic silver liquid coat a dime and roll around in my hand....

    Ain't nu-nu-nu-nutin wrong-gu-gu-gu wit meeee!

    DuPont has information on PCB's as well as the EPA.

    Toast
    veritas odium parit

    Comment


      #3
      Re: PCB oil, what part contains it?

      at least you are not trying to find the part containing snake oil in a l&c... which that part would be the sticker...

      i would replace the failed caps... rubber gloves might be helpful...
      sigpic

      (Insert witty quote here)

      Comment


        #4
        Re: PCB oil, what part contains it?

        It's the transformer

        And I have a funny story to retell you
        A guy I know that is into motorcycle racing also ran a business on the side, repairing misc Lathes, Mills etc CNC machines

        One day he came to a company with a really big step down transformer, 20kVAC down to 400VAC
        He asked them what all the oil underneath it was?
        -They answered the had changed the oil, because they thought "it might need an oil change"

        Mind you this was PCB oil, so toxic it is silly
        They had replaced it by pouring it into some misc Jar etc, spilled it all over their hands and so on
        Then the geniuses had dug it down outside, and this was close to rivers etc

        Next day that place was swarming with digging equipment, he called the government and let them know, had to pay a realllly hefty fine for that "mishap"
        So, even tho this is a small little thing in comparison, please don't do anything stupid with it

        Also of note is that these oils are never changed, they don't deteriorate (because they are so fucking toxic, mental note, all really toxic things generally work really fucking well!)
        "The one who says it cannot be done should never interrupt the one who is doing it."

        Comment


          #5
          Re: PCB oil, what part contains it?

          Not that kind of transformers in that equipment. The external bolts and end bells are standard dry transformers with no oil. A true oil-filled transformer is a sealed box with sealed connections. Otherwise change all big electrolytic capacitors and dispose of it according to EPA. Other capacitors that are wax or paper capacitors are dry type and need to be replaced as they are bad now.

          Ratdude747, PCB is very nasty stuff. Not easy to dispose of and only effective way is extremely high temp specialized incinerator over 2,000C IIRC.

          Cheers, Wizard

          Comment


            #6
            Re: PCB oil, what part contains it?

            Wizard; are you sure, you saw the transformer in the first pic?
            Because there is an open frame transformer in the other two pictures...

            I'm not in any way claiming to be correct, I just want to confirm you are, so poor Maxxarcade doesn't end up with cancer :/
            "The one who says it cannot be done should never interrupt the one who is doing it."

            Comment


              #7
              Re: PCB oil, what part contains it?

              As I noted, the main transformer is "potted" with an asphalt tar, which in the early days, did contain PCB's. The oily substance is "weeping" from the tar. I probably should have made that more clear.

              The other transformers are sealed with either paraffin or lacquer and pose no problem.

              Attached is DuPont's PCB sheet.
              Attached Files
              veritas odium parit

              Comment


                #8
                Re: PCB oil, what part contains it?

                Should we go after the inventor of PCBs, Monsanto? They knew about the hazards before WWII.
                And would eBay have policies regarding products or components containing PCBs?
                My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.

                Comment


                  #9
                  Re: PCB oil, what part contains it?

                  Absolutely! . . . but don't forget GE:

                  http://www.rawfoodinfo.com/articles/...xichudson.html

                  Then we need to get rid of the lawyers, congressmen, some judges (all the way to the Supreme Court).

                  Let's make sure Vietnam gets a part of Monsanto's ass too. (Agent Orange)

                  And stop buying RoundUp and lining their pockets. $4 Billion last year alone in just that product.

                  Good luck with this...
                  veritas odium parit

                  Comment


                    #10
                    Re: PCB oil, what part contains it?

                    Originally posted by Toasty View Post
                    And stop buying RoundUp and lining their pockets. $4 Billion last year alone in just that product.
                    but roundup is always on sale... will remember not to buy roundup...
                    sigpic

                    (Insert witty quote here)

                    Comment


                      #11
                      Re: PCB oil, what part contains it?

                      Why was it potted in tar couldn't they have used thermal epoxy like they use in modern flybacks?
                      Last edited by Krankshaft; 08-14-2010, 09:49 PM.
                      Elements of the past and the future combining to make something not quite as good as either.

                      Comment


                        #12
                        Re: PCB oil, what part contains it?

                        No no. You do not have that kind of oil-filled transformer design due to external bolts and visible laminations with end bells covers. The core will not be visible in true oil-filled transformer.

                        Tarred or pitch transformers does not have oil. Also there are plenty of transformers that is not sealed at all, just dry and probably sealed with shellac or varnish except high voltage around 200-500V or HV for CRT probably sealed with tar or pitch in that vintage. What I mean is a totally enclosed container usually a sealed BOX with terminals on top or on the sides and your pictures does not have that type, get more pictures? But this small oil-filled transformer is a exception as very rare few used oil filled transformers that small.

                        High voltage after mid 60's and commonly after 70's tend to be epoxy filled then placed in vacuum chamber while epoxy is still fluid and vacuum pulled to degas bubbles to insure HV winding and HV components (resistors and diodes) all encapsulated thoroughly. They do same with some transformers and varnish for quality reasons and prevent mechanical hum noise.

                        On other hand, there are some oil filled or dampened capacitors always large one in metal can with terminal or more, very reliable but their age is usually the seals leak. Also there are large capacitors that contains little electrolyte. You are better off finding a vintage electronics forum where they do old vintage and ask which item that is oil filled part that is truly PCB containing.

                        Smaller capacitors that is paper or wax, or early molded capacitors:
                        Paper or wax capacitors does not have much oil, just dampened oil or electrolyte insulation separators. Oil containing caps tend to be large and in metal can. Especially the electrolyte paste dry out because of seal failure of age. Also majority of paper and also wax capacitors, plastic molded old capacitors is dry type. They fail due to moisture (humidity) seeping into dry paper separator and paper become acidic and corrode aluminum foil. This becomes leaky (electrically) or short out. In some case these leaky wax or paper cap explode when power is applied.

                        Cheers, Wizard
                        Last edited by Wizard; 08-15-2010, 01:21 PM.

                        Comment


                          #13
                          Re: PCB oil, what part contains it?

                          I think these are good examples of what could be oil filled transformers and caps.

                          The big transformer in this scope had been replaced at some point. There was a brown puddle underneath where I'm guessing the original had leaked. I wasn't too happy when some of it got on my hands. I ended up parting out the scope, and keeping the transformer and some tubes.





                          This signal generator is probably what should have had the PCB sticker. Lots of big rectangular can caps with rubber seals around the terminals. None seem to be leaking, but the whole thing has an oily smell when it warms up

                          Comment


                            #14
                            Re: PCB oil, what part contains it?

                            maybe someone oiled the shaft on that air-spaced varicap.

                            Comment


                              #15
                              Re: PCB oil, what part contains it?

                              The only real danger with PCB caps or transformers for that matter is when the seals fail and they leak. If they aren't leaking they're safe.

                              On a related note I know US step down pole transformers had PCBs in them. Did they remove them from service, drain and retro fill them, or just replace them as they broke? Just curious.
                              Elements of the past and the future combining to make something not quite as good as either.

                              Comment

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