odd things simple fix

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droopy

Member
Location
Gilbert, WV usa
What's the oddest problem that has occurred that you know of with the simplest fix. Ex. I heard of a coal mine in ky lost power underground because the rectifier went down. Electrical engineer and superintendents all looked at it and determined the problem was a timer. They ordered the part said it would take one month to get. An electrican from the mines went and looked at it and asked the boss could he borrow a vehicle came back thirty minutes later walked over fixed it. Put phases in and back to work. They asked him how he said the timer was the same as a washing machine and someone had discarded one in the dumpster. Timer lasted longer than the coal mines.
 

John120/240

Senior Member
Location
Olathe, Kansas
One job years ago, Every time the homeowner used the toaster (pushed down on the handle) it turned on the garbage disposal. Another one,Drunk Yahoo ran the garage door low voltage to the front door bell button. Then of course try to open the garage door & it rang the door bell.
 

PetrosA

Senior Member
The closest I can come is from back when I had my cafe. My dishwasher sprung a leak in the hose that circulated between the basin, pump and sprayer arm. Specialty part, service guy couldn't get there for three days, no local parts store, and I would have to shut down till it was fixed. I took it with me to a parts place for tractor trailers, got a radiator hose that had almost the same bends plus some, cut them off and installed it and was back up and running within three hours.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Had a customer in Adelanto CA, in the middle of nowhere between LA and Vegas, with a soft starter on a large blower at a melt furnace giving him trouble. The soft starter kept tripping on shorted SCR, but when his shop electrician tested it, they were fine and the soft starter worked fine again after testing it. As a general rule when SCRs fail, they fail for good, there is no "maybe" about it because they become full time conductors and stay that way. But it kept happening over and over, so I assumed it must be a problem with the detection circuit and sent them a new board. It still happened, so I took a new soft starter out there and put it in. Worked fine, and as I was driving home, I got a call that the same fricken thing was happening with the new one. Tripping on shorted SCR, but the SCRs tested out fine, then the starter worked again. I spent the rest of that day and most of the next out there, watching it, and sure enough, every now and then it would trip, only when not running the motor (that's the only time you can detect them anyway). I did figure out that testing had nothing to do with it, powering it down to do the test was resetting the fault and it would work for a while, then trip.

After watching it do this over and over all day long the second day, I finally noticed a sound in the shop changing at the exact same time as the trip. I followed the sound and found a 25HP air compressor running outside that had just turned on. So I experimented and sure enough, every time the compressor turned OFF when the soft starter was not running its motor, the soft starter tripped. What was happening was that the coil on the compressor starter was line voltage, they ran the 480V line right through the pressure switch to the starter coil. When the coil de-energized, it gave an inductive kickback spike of voltage on the 480V line that caused the SCRs on that phase to turn themselves on from a brief fraction of a second, but it was long enough for the Shorted SCR detection circuit to think that because the voltage drop across the SCR went away, the SCR was shorted. It's something I had forgotten could happen because I had not seen a line voltage coil on anything in decades! It was common at the still mill where I started as an electrician in the 70s, but people stopped doing that.

So I knew I needed a snubber on the coil, but there is nothing in that town but a Radio Shack. They didn't know what a snubber was, nor did they have an MOV, so I had to buy resistors and a capacitor to make my own. But because it was radio shack, selection was limited and nothing was rated high enough for 480V. So I had to string together a bunch of smaller resistors and parallel some caps to make it work and connect them with solder, making a string of parts about 6" long. I put them into a piece of heat shrink tube with just the leads peaking out of each end to attach to the coil terminals. It was butt ugly, but it worked! I told the plant electrician to order a real coil snubber for that starter from Sq. D, because I didn't like the chances of my string of Radio Shack parts lasting.

4 years later I was driving through there coming back from Vegas and I stopped in to see them, the $12 string of parts was still there, still working.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
What's the oddest problem that has occurred that you know of with the simplest fix. Ex. I heard of a coal mine in ky lost power underground because the rectifier went down. Electrical engineer and superintendents all looked at it and determined the problem was a timer. They ordered the part said it would take one month to get. An electrican from the mines went and looked at it and asked the boss could he borrow a vehicle came back thirty minutes later walked over fixed it. Put phases in and back to work. They asked him how he said the timer was the same as a washing machine and someone had discarded one in the dumpster. Timer lasted longer than the coal mines.

The place I used to work made a standard control system out of a Mallory timer that was otherwise mostly used on washing machines. Sold thousands of them on our equipment over the years until Mallory discontinued the part.
 

Barbqranch

Senior Member
Location
Arcata, CA
Occupation
Plant maintenance electrician Semi-retired
When I was a young pup and driving a delivery truck, one of my gas station customers had a (purely mechanical) candy machine where people would sometimes lose their money. Since I had experience in that area, I offered to look at it. With the door open, and my trouble light on, it always worked. Turn off the light, and it would fail half the time. Light on, worked.

Turned out that when I turned my light out, I pulled the handle more quickly, with light on pulled it slowly to watch the pieces move.

Fixed it with a sign saying "pull handle slowly, or you will lose your money."
 

kwired

Electron manager
Location
NE Nebraska
Too many incidents to recall, but some of the simplest seem to be for motor overload trips. You can't tell an owner/operator/etc. that something is overloaded - you have to show them why it is overloaded most of the time otherwise "that damn thing we need to reset all the time must have something wrong with it". Have had to prove to many they had bad bearings on something, something plugged, product inside when it shouldn't be, product not present when it should be equipment not assembled correctly after cleaning or other maintenance or just worn out machinery but motor driving it is just fine.
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
My brother in law told a story from his military days of a problem with a new turboprop aircraft. He was stationed in an area that had lots of wind, enough to cause the props to spin, making it impossible for the maintenance crews to do any work on the engine. They sent out a request for proposals for a braking system that would keep the props from rotating with the wind. Several suggestions for multi-million dollar systems were submitted. Then one day, someone stuck a broom handle in the prop housing. Problem solved.
 

RichB

Senior Member
Location
Tacoma, Wa
Occupation
Electrician/Electrical Inspector
Heard a story relating to Boeing--When they were first playing with a monocoque fuselage panels for the soon to be B-17 the panels would more often than not get stuck in the forming dies--Had all the aircraft and equipment designers around trying to figure out why and how to fix it--

The plant oiler, who had never made it to high school, happened by he took a look over their shoulders and asked a simple question--"Have you tried a little oil or grease on it?"

Light coat of light oil and all worked fine.

.I had a 1" conduit in a high vibration area--going up the in-feed conveyor on a bark hog at a sawmill--Kept coming apart at an Erickson--so the next time it happened on my shift I used a water pipe union--got yelled at by the boss but when it never broke again he relented
 

sii

Senior Member
Location
Nebraska
I made a quick trip home to see my dad one Friday after work, about 120 miles. Got called from work, hydraulic press used for removing a plastic part from it's mold would not run....."we've tried everything". I drove home and went to work where the entire crew of four guys is sitting in the break room smoking, waiting for me. Took me thirty seconds to find a 1/2" nut stuck under the footswitch preventing the machine from cycling.
 

mwm1752

Senior Member
Location
Aspen, Colo
NOt really a make shift -- As an apprentice and the old codger I worked with was very knowledgeable. One day the welder was explaining a great deal he had on a drill press mounted on the back of the truck. The only problem was he couldn't find the left twist bits that were needed to use it. This old sparky kept talkin up all sorts of million dollar fixes until he bargained for a case of cold beer. The welder jumped at the deal. He pulls out a screw driver loosens the houding & moves it 90 degs tightens it back up & demands payment. The look on that welders face was priceless when the press rotation was reversed we drank beer for at least two weeks.

Had another troubleshoot on a job for the local inspectors -- they had put up a track on an existing lighting outlet, installed the heads but no illumination. As a side note both were also bartenders at the Eagles Club. I checked the switch legs & sure enough voltage was available. Looked at the track and apparently when they installed the interior cooper conductor had slid out of the track so no connection to the head could be made. Got a few beverages to keep that one a secret.
 
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junkhound

Senior Member
Location
Renton, WA
Occupation
EE, power electronics specialty
motor reversal - inspired by mod removed newbie question in the 'general' section.
asked why motor would not reverse when leads switched as instructed on nameplate -

well, guy was reversing the red and black line leads, not the starter winding leads, wondered why the motor kept turning same direction !

more subtle:
Space station shuttle luminaire showed arc marks on both sides of housing (edit- arc marks on the interface mating surfaces) when dis-assembled during qualification testing - why? Both sides of clamshell housing are grounded and housing faying surfaces conductive, should be no current there.
Turns out during launch vibration testing, when vibration table goes up onto oil film, facility ground currents flowed thru housing - vibration lab in same area as other BIG equipment - e.g. next bay, a C-17 was being raised and dropped a few times a minute to test landing gear lifetime, big HP motors, LOTS of stray neutral currents in that StL facility.
 

dfmischler

Senior Member
Location
Western NY
Occupation
Facilities Manager
At one time I worked for a company that made/sold/leased toll systems equipment. I was involved in building a coin counting machine (remember the baskets you threw change in to pay your toll?). It measured coins with an optical shaft encoder and analyzed metal content by measuring the effect on a coil's response to a frequency. Bad coins were diverted into a reject vault through a solenoid-operated door in the mechanism. The first production machines would jam whenever a steel slug was fed into the machine. Turns out that the slug was sticking to the door until the solenoid was turned off because the magnetic field from the solenoid was getting coupled through a plain steel screw. When those screws were replaced with the stainless steel screws called for in the parts list the magnetic flux was no longer enough to make the slugs stick, and the machine ran properly.

Our head of manufacturing told me he fixed the problem by making "MIL-TFD-41C" the new production standard. I said, "What's that? Some new military standard?" He beamed and said, "No, it's kind of an acronym for Make It Like The Fine Drawing 4 Once."
 

kwired

Electron manager
Location
NE Nebraska
My brother in law told a story from his military days of a problem with a new turboprop aircraft. He was stationed in an area that had lots of wind, enough to cause the props to spin, making it impossible for the maintenance crews to do any work on the engine. They sent out a request for proposals for a braking system that would keep the props from rotating with the wind. Several suggestions for multi-million dollar systems were submitted. Then one day, someone stuck a broom handle in the prop housing. Problem solved.

Reminds me of a story I think I got from this site some time ago. Can't seem to find it though, but was a story about a production line and they were having problems with empty boxes showing up at the end of the line. They spent many many dollars on engineering and researching to find a solution to this problem and their results ended up shutting down the entire line when an empty box was detected. Later some of those involved in the design came to check out how it worked had found that an operator came up with a solution of pointing a simple $20 household fan at the conveyor that would blow empty boxes off the conveyor instead of shutting down the whole line, because it was much simpler then having to start up the system again just for an empty box here and there.



Heard a story relating to Boeing--When they were first playing with a monocoque fuselage panels for the soon to be B-17 the panels would more often than not get stuck in the forming dies--Had all the aircraft and equipment designers around trying to figure out why and how to fix it--

The plant oiler, who had never made it to high school, happened by he took a look over their shoulders and asked a simple question--"Have you tried a little oil or grease on it?"

Light coat of light oil and all worked fine.

.I had a 1" conduit in a high vibration area--going up the in-feed conveyor on a bark hog at a sawmill--Kept coming apart at an Erickson--so the next time it happened on my shift I used a water pipe union--got yelled at by the boss but when it never broke again he relented
Some explosion proof unions are similar in design to a regular pipe union.... if you want to have something listed to use.
 
There's always one small difference- instruments run off a different PS, data cables plugged in upside-down (26 & 40 pin headers) or off by one column, shield bonded at both ends but the far end sensor is on the bench, etc etc. Had one where the new operator took their foot off the switch a little too early and didn't let the machine really finish the cycle.


Our head of manufacturing told me he fixed the problem by making "MIL-TFD-41C" the new production standard. I said, "What's that? Some new military standard?" He beamed and said, "No, it's kind of an acronym for Make It Like The Fine Drawing 4 Once."

That, my friend, is a keeper :D.

There's the story of a farmer who went to work on the railroad, but didn't want to seem to ignorant of their ways, so when someone corrected what he did, he always said "That's not how we did it on the TM&P." Nobody knew all the various small railroads around the state, so folks just accepted that. Finally, when someone asked about the TM&P, the farmer grinned and replied, "Oh, that's the Two Mules and a Plow."
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
How about when the best solution to a problem is to discover that there never was a problem in the first place? In tribute to Leonard Nimoy (in pace requiescat), here is a story from the early days of filming the Star Trek series.

The producer had a hard time finding the right make up products to give the Spock character the green shade he wanted for Spock?s skin tone. They would try a color, shoot a scene, and when the proofs came in the next day, Spock?s skin tone looked exactly like the actor?s true skin tone. The next day they would try a different product and a different color, and the following morning the proofs had the same result: no green skin for Spock. It frustrated the producer to no end. Finally, one of the production assistants came to the producer with a complaint over all the work the post-production people had to go through all night, just to retouch the film (frame-by-frame) to remove that strange green tone that kept showing up on Nimoy?s face. :slaphead:
 
[h=2]Repost from last year:

Best troubleshooting call in years[/h]
Got called to a multi-million dollar home (that's not really saying much in the Bay Area).

There was an electrical hum in the master bedroom, such that the owner couldn't sleep in the room for the last 6 weeks.

1 general contractor, 2 electricians, one handy-man, and one "astrophysicist" friend had all tried to find the problem, but were unsuccessful.

We traced the noise with a telephone tracing amplifier tool and a stethoscope. The owner had thought it was coming from the wall behind the bed, but we could actually hear it in the floor, as well as in the kitchen ceiling below.

Shut off all power to the house, noise still present.

With all power off in house (amazing how much noise is present from electrical devices), did more tracing with the stethoscope.
The sound was seemed to be the loudest on the massive, wooden bedframe.

Dug out the bed linens, and found a Bulova watch, the one know for the "tuning fork" for accuracy. The watch back was flat against the backboard, and the "tuning fork" in the watch was vibrating against the wood, resonating through the bedframe, much like a piano resonates when the keys are struck, causing the hum.

Took 2 journeyman and an apprentice 2 hours to find. Customer said it was the best $500 she ever spent. She promised us a good write up in "Yelp".:thumbsup:​
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
NOt really a make shift -- As an apprentice and the old codger I worked with was very knowledgeable. One day the welder was explaining a great deal he had on a drill press mounted on the back of the truck. The only problem was he couldn't find the left twist bits that were needed to use it. This old sparky kept talkin up all sorts of million dollar fixes until he bargained for a case of cold beer. The welder jumped at the deal. He pulls out a screw driver loosens the houding & moves it 90 degs tightens it back up & demands payment. The look on that welders face was priceless when the press rotation was reversed we drank beer for at least two weeks.

That is AMAZING!! You made a case of beer last TWO WEEKS??? :D
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
When I was working in the semiconductor biz, a problem came up when a new version of a chip was being designed while I was out on vacation. The product engineers had determined that the chip had to have two different test modes, and the other engineers in my group had been scratching their heads over how to make the test pin on the chip make the chip go into three modes (operation, test1, and test2). They were simulating transistor stacks that could tell the difference between three different voltages on the pin and the logic that would be triggered by the three states, but there were problems.

I came back from vacation and looked over what they were doing, and I felt a bit overwhelmed by the catching up I would have to do to get up to speed to help solve the problem. Being the lazy engineer I was and am (some will say that is redundant), I went into my boss' office and asked him, "Why can't we just have two test pins?" He just looked at me. Then he said, "Damn!" and picked up his phone and started calling people. I got a raise.
 
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TobyD

Senior Member
I received a call from a older lady .She was concerned about a strange noise in here attic space.The noise was directly above her breaker panel .So naturally she thought the service was going to catch fire due to squirrels chewing on the wiring.Well, all looked good in the attic., Still ever so often I too heard a sound resembling a pig snorting.As I checked , form the outside there was a forked branch from a tree growing up into the overhead power drop.Each time the limb move it sounded like a big grunting hog in in attic.A quick cut with the trusty hand saw and the problem was solved.
 
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