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anyone recommend an earth leakage clamp meter ?

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    well, the constant resistance may be caused by carbon tracking!
    i wonder if some type of RF injection would help find the spot?

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      also, is it roughly 60k or did you use a meter with lots of digits?
      maybe a precision meter would help position it.

      Comment


        Originally posted by stj View Post
        also, is it roughly 60k or did you use a meter with lots of digits?
        maybe a precision meter would help position it.
        it settles roughly 60k .not exact as it does change a bit and takes a few seconds to settle like its also picking up capacitance which i expect on such a long run . i really should have use the megger on it , when i swap out the isolator switch i will use the megger instead of the dmm . i was nursing a huge hangover and shouldn't really have been messing around with live mains . i had to disconnect whilst checking stuff . where the wires connect to the supply is a dark place and my torch battery decided to run rather low on charge so was hard to see things . its a bit odd as a few times the 60k wasn't there at all and had me touching my meter leads together for my sanity . another thing i noticed was the armour was connecting to the earth wire so i guess there is a split letting water into the cable . i wa told there is a kink in the cable that's been there a long time but i haven't looked at that yet . might have to check that out to see if its getting warm .

        Comment


          The 60k reading will move - the multimeter (Ohms) DC current causes electrolysis like charging a battery with the water and metals there. Try flip polarity and watch the reading.
          Another approach is measure DCV to get an idea if it's wet. 3-wire? Or measure Ohms between all conductors and the armour, 4 possible readings to see if how much is leaking to what.
          Line/Hot will make water boil and steam and make gurgling sounds if immersed, as a give away.
          If many wet readings, I'd prepare to dig up the splice. The water will eventually corrode the conductors and the cable go open circuit.

          Do you have frost and soil heaves? That moves cables around unless 1-2m below surface here.

          Comment


            Originally posted by redwire View Post
            The 60k reading will move - the multimeter (Ohms) DC current causes electrolysis like charging a battery with the water and metals there. Try flip polarity and watch the reading.
            Another approach is measure DCV to get an idea if it's wet. 3-wire? Or measure Ohms between all conductors and the armour, 4 possible readings to see if how much is leaking to what.
            Line/Hot will make water boil and steam and make gurgling sounds if immersed, as a give away.
            If many wet readings, I'd prepare to dig up the splice. The water will eventually corrode the conductors and the cable go open circuit.

            Do you have frost and soil heaves? That moves cables around unless 1-2m below surface here.
            yes its 3 wire but now using 2 of them . the armour is also floating but appears to be grounded somehow so the outer casing is compromised maybe at the splice but i would expect that to stay wet longer being buried . one thing to note is only some of the cable is buried the rest is laying on the ground . i am very tempted to cut it roughly in half to see which half the problem is in . then if definitely in one half cut that one in half and replace the bad quarter to save him loads of money .

            Comment


              the armor is supposed to be earthed, the metal bits that mount the wire to a box see to that.

              Comment


                Originally posted by stj View Post
                the armor is supposed to be earthed, the metal bits that mount the wire to a box see to that.
                yes i know it should only connect at supply end really in case of a fault that could make all grounds live . anyway both ends disconnected for testing at the moment . i cant see this causing a problem just when it rains

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                  Originally posted by petehall347 View Post

                  yes i know it should only connect at supply end really in case of a fault that could make all grounds live . anyway both ends disconnected for testing at the moment . i cant see this causing a problem just when it rains
                  Did you do an insulation test yet?

                  Comment


                    Originally posted by CapLeaker View Post

                    Did you do an insulation test yet?
                    if you mean with the megger not yet . will do once i have the new switch and wires disconnected both ends , i could also do a psc test but not sure if that will help here
                    this is same as my insulation tester .
                    Click image for larger version

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                    Last edited by petehall347; 07-10-2024, 05:43 AM.

                    Comment


                      Originally posted by petehall347 View Post

                      if you mean with the megger not yet . will do once i have the new switch and wires disconnected both ends , i could also do a psc test but not sure if that will help here
                      this is same as my insulation tester .
                      Click image for larger version

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                      Yes, with a Megger or equivalent. This should show leakage real fast. I use the Fluke 1587FC for all these leakage tests. I don't use it every day, but every time I need it, it's a freaking god send for me.

                      Comment


                        insulation test failed . especially live to ground and ground to armour 0.0 others at 0.3 .. they all should be better than 1.0 hardly any difference testing from both ends of the swa cable .

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                          mystery solved when one of the lads was looking for the resin joint i did years ago after some idiot lit a fire on it . this is jcb damage from a year or two back . i did warn him about the cables . looks like he badly damaged it then attempted to do a quick tape up job . .. makes the mind boggle it does . now we have to get another resin kit and do a proper repair .. Click image for larger version  Name:	20240711_191347.jpg Views:	0 Size:	3.30 MB ID:	3307364

                          Comment


                            Sweet! I figured it would fail that insulation test and there must be some trouble somewhere. Glad you found it.

                            Comment


                              Originally posted by petehall347 View Post
                              mystery solved when one of the lads was looking for the resin joint i did years ago after some idiot lit a fire on it . this is jcb damage from a year or two back . i did warn him about the cables . looks like he badly damaged it then attempted to do a quick tape up job . .. makes the mind boggle it does . now we have to get another resin kit and do a proper repair .. Click image for larger version Name:	20240711_191347.jpg Views:	0 Size:	3.30 MB ID:	3307364
                              Why do you not have this cable in a outdoor rated conduit in this country you are required to use outdoor conduit for running electrical wiring except for landscaping lighting 12 volts or under that voltage if I was running landscaping lighting and it was going to be permanent I would use conduit even for this

                              9 PC LCD Monitor
                              6 LCD Flat Screen TV
                              30 Desk Top Switching Power Supply
                              10 Battery Charger Switching Power Supply for Power Tool
                              6 18v Lithium Battery Power Boards for Tool Battery Packs
                              1 XBox 360 Switching Power Supply and M Board
                              25 Servo Drives 220/460 3 Phase
                              6 De-soldering Station Switching Power Supply 1 Power Supply
                              1 Dell Mother Board
                              15 Computer Power Supply
                              1 HP Printer Supply & Control Board * lighting finished it *

                              These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%
                              1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
                              2 Hem Saw Computer Stack Board
                              All of these had CAPs POOF
                              All of the mosfet that are taken out by bad caps

                              Comment


                                Originally posted by sam_sam_sam View Post

                                Why do you not have this cable in a outdoor rated conduit in this country you are required to use outdoor conduit for running electrical wiring except for landscaping lighting 12 volts or under that voltage if I was running landscaping lighting and it was going to be permanent I would use conduit even for this
                                its swa steel wire armoured it can live outside for 50 years if some idiot doesn't damage it with a large machine then try and hide the fact after being told it was there . the repair wont take long but finding the damage has taken hours and money . if it was in conduit matters might have been much worse . cant even imagine pulling over 100 metres through conduit around bends and over uneven surfaces ,

                                Comment


                                  Unfortunately you can do anything for someone who does not listen you when you tell them that are electrical wiring in a certain place or area and what is even worse is that they do not tell you that they damaged it so it could have been fixed properly the first time what kind-a contractors are these people anyway

                                  The reason why you use plastic outside rated conduit is that when you are digging you will see the conduit and you know where the wiring is yes we have underground cable here but I still put it in outdoor conduit anyway

                                  I would agree with you if it gets damaged it is harder to deal with but me personally I do not like making splices that are underground for any reason I would rather just have it come up three feet and go back underground for peace of mind and not have breakers tripping when it rains real heavy but that's just me
                                  Last edited by sam_sam_sam; 07-11-2024, 07:53 PM.
                                  9 PC LCD Monitor
                                  6 LCD Flat Screen TV
                                  30 Desk Top Switching Power Supply
                                  10 Battery Charger Switching Power Supply for Power Tool
                                  6 18v Lithium Battery Power Boards for Tool Battery Packs
                                  1 XBox 360 Switching Power Supply and M Board
                                  25 Servo Drives 220/460 3 Phase
                                  6 De-soldering Station Switching Power Supply 1 Power Supply
                                  1 Dell Mother Board
                                  15 Computer Power Supply
                                  1 HP Printer Supply & Control Board * lighting finished it *

                                  These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%
                                  1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
                                  2 Hem Saw Computer Stack Board
                                  All of these had CAPs POOF
                                  All of the mosfet that are taken out by bad caps

                                  Comment


                                    it's only 240v though - atleast it wasnt 3-phase

                                    Comment


                                      that's better now .... Click image for larger version

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                                      Comment


                                        still some insulation leakage going on but that bit looks the worst from i can see , might be the old joiner letting damp in . its hard to tell .. thinking of getting a thermal imaging camera and putting a heavy load on it and looking for hot spots .

                                        Comment


                                          Originally posted by petehall347 View Post
                                          thinking of getting a thermal imaging camera and putting a heavy load on it and looking for hot spots .
                                          This is probably a good way of seeing if's a bad connection somewhere but you could still use a megger but here is how I would do where ever you have a spliced connection repair I would soak them one at a time and see if your resistance goes down or not if it does not go to the next spliced connection repair and do the whole cable that way if you do not find anything else at this point you are going to have very hard time figuring out what is still causing the breaker to trip but if it is been in service for a long time I might consider replacing it with a new one if you still have issues then I would recommend inspecting every inch of the cable for nicks and signs of corrosion or pitting of any kind check those areas as well

                                          9 PC LCD Monitor
                                          6 LCD Flat Screen TV
                                          30 Desk Top Switching Power Supply
                                          10 Battery Charger Switching Power Supply for Power Tool
                                          6 18v Lithium Battery Power Boards for Tool Battery Packs
                                          1 XBox 360 Switching Power Supply and M Board
                                          25 Servo Drives 220/460 3 Phase
                                          6 De-soldering Station Switching Power Supply 1 Power Supply
                                          1 Dell Mother Board
                                          15 Computer Power Supply
                                          1 HP Printer Supply & Control Board * lighting finished it *

                                          These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%
                                          1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
                                          2 Hem Saw Computer Stack Board
                                          All of these had CAPs POOF
                                          All of the mosfet that are taken out by bad caps

                                          Comment

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