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CJDave
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Got the gen set, no outage.
12/14/07 08:16 PM
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 I have thee most beautiful setup for standby power that you could ever ask for  and ...... well, .... we haven't lost power? On Sunday's 5-something-o'clock evening news the weather man all but GUARANTEED us that we would be outa power by Tuesday so I got out of my recliner and beat feet to Menard's for a generator on sale. I got there fifteen minutes before closing time and they had two left. I bagged one and was headed for home by seven PM. On Monday I serviced the unit and test ran it with some temporary cables. I filled up my fuel cans and got them ready. It was a pretty wild Monday night and we did get one heck of a lot of ice, but we were just a bit south and west of the main front and were kind of going from ice-to melting-to-ice-to melting all day on Tuesday. We had some pretty serious power winks, but the juice stayed on. Just twenty miles farther west is a MESS. Trees and poles and lines down all over the place. Our daughter and her husband bought a Menard's generator too and were just getting it set up and testing the engine when POOF their power went out.
 Yes, what we have here is a teeny unit, only 5500 watts, and yes, I have always intended to buy a big unit (10,000+) on Propane, but this was one of those cases where "intend" might have left us out of power so we bought this intrim unit. We have had our house double-wired for a generator ever since we remodeled in '02. '03, and '04; but power outages were so infrequent that we never bought a generator. We had never seen an ice storm until last February.  Oh well, at least I finally got busy and finished out my standby power system; getting the neutrals isolated and the permanent cables made up. I'm setting everything up for 50 AMPS 240V , even though this little unit is less than half that. We still INTEND to get that big one someday.
CJDave
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egon
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Re: Got the gen set, no outage.
[re: CJDave]
12/15/07 01:02 AM
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If your really serious about trying out the generator get some fishing line, some chain and take a walk down the road and do some casting! 
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CJDave
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Re: Got the gen set, no outage.
[re: egon]
12/15/07 05:54 PM
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I'm going to have to wait until the batteries in the new emergency lighting unit are completely charged; it takes 48 hours, and I just plugged them in this morning. I sure wouldn't want to wrestle the gen set into position in the dark.
CJDave
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Pat
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Re: Got the gen set, no outage.
[re: CJDave]
12/18/07 11:18 AM
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Dave, I too have had thoughts/intentionis of maybe getting a genset like Gary has. I want propane fuel with auto start and auto switching of the mains.
10-12 Kw should be ample.
What I do have is a couple of smaller ones, one is 6Kw steady state manual start and the other is "rated" for 12Kw starting surge and 7 Kw or so steady state manual or electric start.
Even after you get your FINAL SOLUTION it is good to have a redundant backup.
I have a small propane powered genset in my pickup camper and if things required it I could use it to power a few things in the house.
We too were expecting outages but only got a few blinks. Friends 1/2 mile away were out for a day and a half. Not far away were things were hit worse there are still thousands of folks out of power, many in shelters.
Pat
"I'm not from your planet, monkey boy!"
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jml755
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Re: Got the gen set, no outage.
[re: Pat]
12/18/07 08:48 PM
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Pat,
Good to hear you didn't get hit bad. Guaranteed if you didn't have the gens that you would not be surfing the net yet. That storm would have targeted your place.
I put in a Transfer switch and outdoor plug, so the only cord is from the generator (B/S 13.5kw surge, 8kw continuous) to the outside (inlet) plug. The manual transfer switch is 6 circuits and I was lucky that I've got 6 circuits on my main panel that let me have light in all the BRs, baths, some main floor and basement lites without having to do any rewiring or running extension cords. Biggest hassle is rolling out the electric start genny to the back of the house.
Would have put in a whole house unit (natural gas, auto-start, auto-transfer and weekly self-test feature) but we don't plan to be here another 5 years. Next one will surely have one.
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Pat
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Re: Got the gen set, no outage.
[re: jml755]
12/19/07 07:28 AM
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Generators and transfer switches are sort of portable so you could have one now and take it with you without too much hassle.
Right now I have a 21x48 open on one long side shed on the side of my garage-shop (36x48.) As it is well ventilated and not adjacent to a living space and the intake for the fresh air ventilation system is not nearby I keep at least one if not both generators under roof in the shed and they can be run there safely. There is a sub panel there as well for feeding power.
As soon as my list of projects gets rearranged and re-prioritized (it keeps getting longer faster than I can finish off items) I will get an autostart auto transfer setup with a propane fired engine. Propane is just the bee's knees as it has no storage life problems, no pouring gasoline in wind and weather and it gives easy starts in low temps as it is already vapor.
Folks seem to think diesel is the primo fuel for backup generators but not true in most residential installations. There are fuel storage issues and short run issues. Propane burns so clean short runs are not such a big deal and fuel lasts essentially forever without degradation. That, and I have 2 propane tanks at 1000 gal each (800 usable each) so I am covered there.
Pat
"I'm not from your planet, monkey boy!"
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JazzDad
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Re: Got the gen set, no outage.
[re: CJDave]
12/20/07 08:16 AM
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Think of your generator as insurance. Just don't think like some of my customers who want a refund when they don't "use" their insurance. 
All kids are gifted; some just open their packages earlier than others.-Michael Carr
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CJDave
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Re: Got the gen set, no outage.
[re: Pat]
12/21/07 08:12 PM
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Pat, for more than a dozen years I got paid for getting up early and running pre-dawn standby generator tests on everything from hospitals to creameries. I can tell you that automatic transfer switches are not for everyone. They are finicky and complicated, and the only real justification for marrying yourself to one is that when someone is flat on the table in O.R. you NEED that gen set to come on and SWITCH in eight seconds or less so that the heart-lung machine doesn't stay stopped too long. OR....if you have a pool of molten auto windshield glass that HAS to be kept moving or it will take three weeks to restart the process. OTHER THAN THOSE KINDS OF SITUATIONS, the hassle of maintaining auto transfer gear isn't worth the teeny tiny benefit to be derived from instant changeover. I don't even have a double-throw switch on my setup, choosing instead to move large plugs from black, "Normal Power" outlets (50 AMP and 30 AMP) to red, "Emergency Power" outlets which are connected to a red-painted 60 AMP disconnect switch fed by the gen set, and then gleefully and ceremoniously throwing the handle on that red-painted, 60 AMP disconnect switch to "ON".
CJDave
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Pat
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Re: Got the gen set, no outage.
[re: CJDave]
12/22/07 07:58 AM
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Dave, I do understand the expense and complication angle and manually switching IS within my capabilities. With access to good quality connectors at decent prices (would shop the used/surplus market) I would be happy with a set up similar to what you mention. (I'm the guy who hammers copper tubing flat and drills it for machine screws to make my own busses for solar DC setups.)
My motivation for the automatic system is not based solely or even primarily on my convenience or a desire to part with significant numbers of fun tickets. Consider these inputs into decision making:
1. Three refrigerators and a freezer
2. House plumbing
3. Potential for wife home alone
4. Potential for no one at home
5. Area prone to ice storms and lightning initiated power outages.
If I could SAFELY assume I would always be home or only a few hours away then manual switching, either home brew or commercial would be a real good option, no doubt. IF my wife was here alone and for some reason the electric start didn't then it gets pretty iffy whether or not she would successfully get a manual start and you can forget switching generators. I'm sure a laminated card with instructions would get her through a home brew changeover from grid to genny OK.
If the dollar value of lost food and rotten meat and the smells and cleanup chores (can you ever get the smell out of a freezer?) and the intrinsic value of the lost food don't equal the cost of the automatic switching, I'd bet you would evaluate the overall hassle as significant enough to warrant regretting not having the automatic feature.
I haven't done it yet. I will have to weigh the facts carefully. I am not hard over toward automatic and am neither for nor against manual. I am leaning toward something on the order of 10Kw propane powered dedicated genset and am slightly predisposed toward a fully automatic setup wtih test runs and the whole enchilada.
For a time I thought I'd get a portable engine run welder and use it as a backup generator. Of course then there is the issue of religiously parking its little trailer in its spot and hooking up the wires to the house so if the wife needed to use it that it would be a likely success. I personally don't think the little combo welder generators make great generators but that is just me.
Life is what happens while you are making other plans. So, right now I have jury rigged portable generator capability that can't be used by my wife if the need arose.
Right now, improving the generator situation isn't near enough to the top of the pile of projects to get me to buying a generator or parts for the system yet.
It was in the 60's yesterday, the 50's overnight, and is forecast for the 20's later on with wind, rain, and snow.
Pat
"I'm not from your planet, monkey boy!"
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CJDave
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Re: Got the gen set, no outage.
[re: Pat]
12/22/07 05:46 PM
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One of the things that is required in facilities with rapid changeover is a DELAY PROVISION for all of the refrigeration compressors. We have a delay relay on the air conditioning, but not on the fridge or the freezer. We had had some on-off-on-off-on cycling from the utility company last summer, which just HAD to be putting the hurt on the refrigerator. I need to brown-out proof the thing, but if I did, I would have to do it with a 24V relay on the input side of the compressor, and that relay would use the same sort of delay timer that my A/C uses. The BIG GRUNT is always getting the gen set going. Once your sweetheart did THAT, a few, red-painted, double throw switches would do the trick, and be a very straightforward system. What you would do is stage them such that she throws number 1 and then number 2, and then number 3. Hospitals are staged according to priority, the TV sets are last of course. The little welders are not usually very good at following the load and the voltage varies tremendously as the engine RPM "hunts" for a sweet spot. Gimme a nice, 12V-71 two-stroke Detroit road oiler anytime. Yeah, they scream at you, and yeah, they leak a lot of oil, but that two-stroke system follows the load better than any four stroker can. Hey,....they fire twice as many times per rev.
CJDave
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Pat
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Re: Got the gen set, no outage.
[re: CJDave]
12/23/07 09:03 AM
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Dave, Thanks for bringing up the delayed restart. I'm sure there are lots of folks who wouldn't think of it.
My thoughts exactly on the combo welder generator. They are good for running tools when not welding but not what I would prefer or recommend for domestic electrical backup.
Dave, think HUGE flywheel on the 4 stroke. Decades back I had a three cylinder two stroke Suzuki so have an appreciation for rapid throttle response. With a cylinder firing every 120 degrees of crank rotation, you got pretty rapid response.
I can tell you are of the mindset into which your experience molded you, a case of every job looking like a nail to a man whose only tool is a hammer. As much as I appreciate diesels and think something like a 3-71 would make a sweet modestly sized diesel genset, the requirements (IMHO) for a domestic standby genset strongly recommend propane. Long storage with no fuel contamination or degradation. Relatively benign periodic short run exercising. Absolutely minimal maint.
Not every household has a professional standby generator tech who may revel in all the little issues of the care and feeding of the diesel genset in a repetitive short run scenario. It isn't that I can't handle the requirements of a diesel standby generator in this class of service, I just don't want to and luckily there are a number of propane alternatives, including gasoline conversions. A propane burning ICE, as you know, has very clean oil and little or no acidic contamination from short runs whereas diesels on the other hand really trash their oil in short run situations and you get accelerated difficulties with bearings and such.
If I were gearing up for a few long term outages, diesel would get much more of my interest but our typical situation is everything from blinks and sub minute outages through several minutes, a few hours or in extreme cases (so far in last 10 years) 3 days. While not so far away there are still folks in the dark or in shelters but we haven't had to suffer such long outages. Half of the closest town was out for a couple days and a friend a half mile away on a different utility was out for a day.
We are on a "main line" so when our power goes out it is a high pri to get it going as LOTS OF FOLKS are down. If you are unlucky to be near the end of the distribution chain and have a local disruption you are in for a long wait as the crews will put in their effort to get the main lines going first as they effect many more folks. A 2-3 family outage is not high pri compared to hundreds or thousands. The outages for which we need a genset are typically only a few hours at most and rarely a few days. A portable gasoline genset would git 'er done, I just want a bit more luxury for my wife and to cover the case where we aren't home when an outage happens as well as it makes things easier for me.
Heating the home during an outage isn't a big deal as we have 3 little gas log parlor stoves and a big gas log fireplace which do not require an external electrical supply as they all have piezoelectric ignition, with self generating safety pilots for thermostatic control. IF we are home, we will have heat. If we are away with the T'stats set down low rather than off to keep pipes from freezing, then automatic start and changeover would be a good thing. Not having to toss out the contents of the refrigerators and freezer would be a good thing too. If it were not for the hassle of the clean up I'd just ignore them as the generator to protect them and the frequency of the needed protection would make taking the chance without a genset would be a viable alternative. This ignores frozen pipes because I could leave some gas logs going with the t'stats turned down.
Of course if you are home, after survival and a modicum of comfort is assured then it doesn't take long before you want your LUXURY back so a genset is not so extravagant and unneeded as some think in our situation.
Oh about the delay. I'd be happy to let the genset delay for 5 min befoer kicking on or even longer if I am away from home.
Pat
"I'm not from your planet, monkey boy!"
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CJDave
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Re: Got the gen set, no outage.
[re: Pat]
12/24/07 05:12 AM
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Yes, those huge flywheels and the rotating mass of the generator rotor are both key to keeping RPM as near constant as possible. With Diesels, turbo lag is definitely a problem when huge loads are brought on all at once. Staging helps with that problem. For home use, there IS no viable alternative to propane in my book. There is a nice TRI-FUEL unit in Northern Tool Catalog that is 13.5 KW and would be perfect for our setup here. It sells for about 3,000 razz-buckniks, a good price, actually. The ONLY thing is, .... the engine runs at 3600, and I would really like to hold out for a slow speed chucker; a four-pole unit that runs 1800. Toys-Is-Us has a store near Silicon Valley in the South Bay Area of CA, and it's one of those deals where somebody else takes care of the generator maintenance. To the store mgmt, it is out of sight and out of mind. A few years ago, the thing went into it's usual weekly freshening run and STAYED ON for like two weeks; running along at high idle. Of course with no load, the fuel lasted almost forever and it was finally discovered when someone asked about the noise. PROPANE is the way to go, but bi-fuel or even tri-fuel is even better. Yeah, Pat, you've definitely got my number, .... if I had my way I'd have a big, squeaky clean, engine room below decks with a 1200 RPM, in-line, Waukesha naturally-aspirated diesel chucker sitting there direct coupled to a Westinghouse six-pole 150 KW generator. Basement engine rooms are not a very good setup if you use gases, especially propane. So if I wanted to use propane I'd have a tight block bldg at ground level with the gen set in there. When we remodeled in '02, '03, and '04, I made sure to leave a good spot in the garage for the gen set to repose. It is real close to the man door that opens onto to the back dock and that spot on the dock is close to our source of propane. Our little set sits in the garage right now in the generator-designated spot, and we only have to roll it a few feet to the outside, fuel it up, stick the cord through the cat door, and connect to the cord that leads to the Emergency Power panel array.
CJDave
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CJDave
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Re: Got the gen set, no outage.
[re: Pat]
12/24/07 05:30 AM
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Here is something that is kind of interesting, ..... The Municipal Airport in Sacramento California is in fogville. When I say fog, we are talking pea soup here; as any California native knows. Of course to an airport, the navigation system is critical, so the power supply is backed up by generators. Their big worry is a car hitting an intersection pole in the fog somewhere and causing an outage just as a Bloogle Airlines jet locks onto the Glide Slope. So, ..... they run ON GENERATOR during periods of fog, the reasoning being that it protects them from an auto crash-caused outage, and if the gen set coughs up the crank, they can switch back in only one second where as going the other way; utility power to gen set; takes about five or six. In 1991, they had a little problem at the airport when they went to switch back to utility power. The big, solenoid-operated, vertical, sliding disconnect de-energized but DIDN'T DROP OUT. The system thought that since the switch was de-energized, well, it MUST have dropped out, but the contacts had welded in. When the system energized the Normal Power sliding switch, the twelve-cylinder Caterpillar gen set met the utility power head on and burned the entire power room to a crisp. it took 11+ hours to get going again and THAT was just for temporary. 
CJDave
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Pat
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Re: Got the gen set, no outage.
[re: CJDave]
12/24/07 09:23 AM
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All because no one worse cased the design and logic. Sense connections to report the actual position of the contactor instead of assuming de-energizing it GUARANTEED its position would have saved all the equipment and most of the hassle.
Pat
"I'm not from your planet, monkey boy!"
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CJDave
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Re: Got the gen set, no outage.
[re: Pat]
12/26/07 02:41 AM
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You know, when I saw that setup for the first time, my first thought was: "Hmmmm... this is unusual." I thought that because I had grown accustomed to seeing the contactors for Normal Power and Emergency Power linked together MECHANICALLY. Little did I know that just six months later it would blamo itself....... as in charcoalville, ....as in lots of burnt insulation and lots of scrap copper. You are absolutely right, the worse case IS the design case, ....or should be.
CJDave
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Pat
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Re: Got the gen set, no outage.
[re: CJDave]
12/26/07 09:31 PM
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You know how it goes, Dave. Some intern summer hire Jr EE major in college checked the logic and didn't find the problem. There are two entirely different mindsets for checking a schematic drawing to see if everything is accounted for in its "logic."
1. The typical one is to assume good inputs to everything. If the right inputs occur does the system do the right thing?
Unfortunately that just doesn't prevent the problem you relate.
2. If some thing is wrong, what does the system do. Industrial robotics is another area where you don't ONLY CHECK to see if the robot does the right thing when it gets the right inputs but will it NOT do a wrong thing if it gets wrong inputs.
I built a computer controlled automated microwave test and analysis system to be carried in an environmental enclosure in the back of a deuce at the NTC at Ft. Irwin. With the help of 2-3 techs I built the system but another outfit was going to program it. A front end pre-amp for a freg counter that goes above 22 GHz is quite expensive and if someone allowed a sig gen to "talk" directly into the preamp without proper attenuator setting during a self cal you'd make thousands of dollars worth of smoke in a fraction of a second. Then the programmers would blame the hardware guys (ME!)
I designed a monitoring system that would latch up and keep red LED's lit showing an unallowed combination of switch positions so that even a temporary glitch in the order of controlling things would be clearly brought to everyones attention. The programers were oh so happy to see that system as it let them test their software with no power to some of the equipment and see if there were any oops conditions in any of their automated procedures.
The point being that you have to think about system logic from both sides: if given the right inputs do you get the right output AND what happens if there are some bad inputs?
Most likely someone glossed over and or never considered what might happen if an electromechanical device with two electrical states and two mechanical states malfunctioned and the mechanical state was unaffected by the electrical state.
Some of us with a little more than just a trace of gray in our beards have probably experienced a relay stuck in the energized position.
Pat
"I'm not from your planet, monkey boy!"
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CJDave
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Re: Got the gen set, no outage.
[re: Pat]
12/27/07 05:49 PM
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One of the toughest aspects of handling large AMP loads is setting the jaw tension on large disconnect switches such that it will transfer current without heating up, but yet pull out when the need arises. SqD has the Bolt-Loc setup, and Pringle has their end-of-stroke tightening sequence, both take extremely astute hadling and adjusting. I have found lots and lots of mains with hot jaws, and always scheduled a re-shoot to see if the repair/adjustment that was performed was effective; there was no other way to tell without using Infrared.
CJDave
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Pat
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Re: Got the gen set, no outage.
[re: CJDave]
12/28/07 10:12 AM
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Non contact IR thermometers are the cat's meow in quite a few areas of application. I have one with the red LED aiming thingy and I just love it.
Sometimes I wish the cone it looked at was tighter but...
Pat
"I'm not from your planet, monkey boy!"
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CJDave
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Re: Got the gen set, no outage.
[re: Pat]
12/28/07 06:27 PM
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That is the beauty of the Videotherm Imaging camera, you can crank the lens down to where it only sees images above a certain temp and that saves lots of time as you sweep whole current carrying systems. When something catches your eye, you go back and focus more specifically on it and then get the non-contact thermometer on it to make sure it isn't just reflection. The camera I use is an ISI Model 94 with a 50MM germainium lens. It reports to a videotape recorder. one heck of a good camera, but kind of a dinosaur by today's standards. It was new in 1989. I have scanned A LOT of gear with it from underground hot water leaks to roof moisture intrusion, to refractory work, to boilers and transformers.
CJDave
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Pat
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Re: Got the gen set, no outage.
[re: CJDave]
12/29/07 01:19 PM
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Dave, I could never justify any thermal image gear. I like to "play" with stuff like that but can't justify buying such expensive toys for which I have no real chance of deriving pay back.
Oh well, there are limits, i guess.
Pat
"I'm not from your planet, monkey boy!"
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CJDave
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Reged: 10/21/02
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Posts: 860
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Loc: Southeast Iowa
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Re: Got the gen set, no outage.
[re: Pat]
12/29/07 06:18 PM
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I bought the 94 in December of 1989 thinking that it would last five years before technology or circuitry difficulties rendered it obsolete. It made me a darn good living for thirteen years and it still actually works but it is an orphan now as the company that built it and in fact designed the main tube was sold several years ago. The whole setup; camera, VCR and support gear cost 21,000 and change. This was one of the first IR cameras that did not have to be cryogenically cooled.
CJDave
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Pat
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Loc: SouthCentral Oklahoma
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Re: Got the gen set, no outage.
[re: CJDave]
12/30/07 09:41 AM
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Dave, I'm sure that the level of technology that is represented by that camera is still quite interesting and useful even if the current state of the practice (not even moving up to state of the art) is way ahead of it. There have been vast improvements since then.
I constantly border on future shock. I have a little telephone tech test box I got in trade with some stuff. It is larger than a pocket multimeter, about the size of an old Simson 260. It does a bunch of computer controlled tests and contains a built in TDR (Time Domain Reflectometer.) I need it like I need a hole in the head but don't have anyone around who could use it or I would make them a great deal.
Pat
"I'm not from your planet, monkey boy!"
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CJDave
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Loc: Southeast Iowa
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Re: Got the gen set, no outage.
[re: Pat]
12/30/07 06:12 PM
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TDR??? Total Digestible Radukomens?  I have like NO IDEA what a device like that is used for. The Time Domains that we use here are not reflective so instead of a flashlight, we find them by letting the dog sniff them out. I have to tell ya, there are times when I feel like a dinosaur around some of this stuff. I'm perfectly at home on my 1952 John Deere Model "A" tractor with the No. 45 front end loader, and the over-center hand clutch. For a fifty-five year old tractor it can move a lot of dirt in an hour, providing it has an experienced John Deere pilot to run it.
CJDave
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Pat
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Re: Got the gen set, no outage.
[re: CJDave]
01/01/08 10:57 AM
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Dave, TDR equipment was in use probably before you were born. What makes having that capability in a small lightweight hand held test set interesting to me is that the equipment used to be huge and heavy.
Transmission lines like twin lead, coax, etc have their natural intrinsic impedance value. You have probably seen and used a balun transformer to convert between 75 ohm coax and 300 ohm twin lead TV wires. (Oh by the way balun stands for BALunced-UNballanced)
If you use a splitter to drive two TV's with an antenna or cable signal the splitter is designed so the single side is a 75 ohm impedance and the other side (double, t ripple, or whatever side) is also 75 ohms at each connection. If you do not match impedances then power transfer is reduced and their is reflected power. Some of the signal bounces off of the discontinuity in impedance and causes reflections (can cause ghosts on your tv) and standing waves.
A short or an open circuit along a transmission line of great length can be a bugger to find. If a pulse of energy is injected into a coax or other transmission line it will propagate donw the line and if there are no discontinuities in the impedance the pulse will not be reflected back, even a little.
We digress again... Tie one end of a rope to a tree. wiggle the rope to make a wave go down the rope to the tree. The wave hits the tree and is reflected back to you. The tree does not match the impedance of the rope.
Dangle a rope over a cliff and do the same as above. The wave travels down the rope and some of the energy is reflected back up the rope. IN the case of the tree the amplitude of the wave at the tree is zero (you don't wave the tree, tree is a "short circuit") in the case of the dangling rope the amplitude is max (open circuit).
Now for your TV cable or other communicatioins transmission line. IF there is a short, an open, or even a discontinuity in impedance due to the cable being partially crushed (stapled too tightly or something) there will be reflections, standing waves and such.
A TDR puts a pulse down the line and detects if there is an echo, timing the two way time of flight of the signal and echo. Knowing the velocity factor of the transmission line you can use the TDR derived time to calculate the distance to the problem. Coax often has a velocity factor ranging from about 0.60 to 0.90 depending on what type cable it is. Velocity factor is the percent of the speed of light that the electrical signal propagates in that particular transmission line.
This will tell a test tech how far down the line there is a problem with the cable. These techniques can be used on cross country power transmission likes. Say a mylar balloon with vacuum deposited aluminum coating from a wedding celebration hits an insulator in a power wire and the wire burns in two. The utility equipment shuts off that wire. You want to go fix it so where is the problem? A TDR will locate the distance to the problem and allow you to efficiently dispatch a repair crew.
Happy New Year!!!!
Pat
"I'm not from your planet, monkey boy!"
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CJDave
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Loc: Southeast Iowa
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Re: Got the gen set, no outage.
[re: Pat]
01/03/08 05:27 AM
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Pat, I have to say that your explanations are about the best I've ever heard. I had no idea anything like a TDR even existed, much less understood how it could be used, .... until now. A farmer friend had a direct-burial cable carrying three-phase 480V to a remote irrigation pump site and the cable was installed without import backfill in rocky soil. Of course the rocks would occasionally press through and cause one leg of the cable to break. He had just over a quarter mile of cable buried so finding the spot was a huge problem. He figured out that if he set his 8N Ford tractor at one end with a spark plug wire connected to the leg of the cable that showed an open circuit, and then let the tractor just idle, he could drive down the cable alignment with his pickup and with the radio tuned slightly off-station, the pickup radio would pick up the static from the sparking when he got near the trouble spot. This stuff is SO interesting!
CJDave
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