US Electrician qualifications for a Brit

On Fri, 27 Oct 2006 04:06:36 GMT Member, Takoma Park Volunteer Fire Department
| I don't claim to have your theoretical expertise but I may have more
| practical experience in farm and ranch electrical problems. Here is one | example of that experience. I had a customer who was having production | problems in his dairy herd. I converted all of his feeders to four wire | and megged his neutrals until I cleared all ground faults. There were | only three. One was in the aging well pump, another in a water trough | heater, and a third one in one of the homes light fixtures. Great, I | thought, I should have this whipped. WRONG. As soon as the neutral | connection was restored animal behavior resumed being erratic and | production fell. During the repairs and updates the farm had been | running on its power take off emergency back up generator to supply the | dairy operation and a portable engine generator to power the | refrigeration and like items by cord and plug in the home. While on | this free standing power the production rose markedly when it should | have fallen. The reason that we expected production to fall was the | absence of ventilating fans in the dairy barns outside of the milking | parlor area. Those of us that were capable of sharing our perceptions | were definitely less comfortable in the barn during this period. To our | surprise the production rose without public power and fell as soon as | it's neutral connection was restored. Keep in mind that while I was | chasing ground faults on the LV neutral a sub contractor was redoing the | entire yard pole and building drop system. While the farms electrical | system was disconnected from the Multi Grounded Neutral of the utility's | medium voltage system production rose. When it was reconnected | production fell. Now I was really confused. I went there to cure what | I strongly suspected was a stray current problem. Having megged all | neutrals clear of ground at 300 volts I couldn't see were the stray | current was coming from but when the sub contractor approached to get | his work order signed off I had a clue. With all stock out to pasture | we shut down both generators and measured for current flow on every | feeder conductor. The entire farm was deenergized at the yard pole but | we had measurable current on all of the feeder Equipment Grounding | Conductors. The readings on these EGCs were only slightly less than the | readings obtained on the old feeder neutrals before starting the upgrade | work. I finally came to the conclusion that the current was coming from | outside the farm property via the utility's medium voltage MGN. When | the utility MGM was disconnected from the premise wiring at the service | equipment the stray current disappeared and production rose. I then | purchased a used three pole switch and all milking and barn feeding was | done with the power fully disconnected from the utility while | negotiations with the utility began. Their first reaction was to attack | my competence. I threatened to file suit for defamation and they agreed | to send an engineer. After the engineer saw my readings using three | different clamp on ammeters and a meter shunt he sent for the utility's | measuring equipment. After measuring for three days they claimed the | condition was normal. The rancher filed suit but more importantly he | called his state senator who, as luck would have it, was serving on the | committee that oversaw the states public service commission. When the | Public Service Commission's engineer denounced the claim of normalcy the | utility began to be civil. I then found out that the tariffs included | single phase 480 as a service option to supply long runs of private | overhead wire to feed customer owned transformers. The utility supplied | that power from a different point on the property line. The only main | bonding jumper on the entire premise became the one at the customer | owned dry transformer that is located at the existing yard pole. There | is now no measurable current flow on the main bonding jumper or any of | the Grounding Electrode Conductors at any of the buildings. Production | stabilized at 15% higher than its previous average. In a two hundred | and fifty head herd that is huge.
How was that 480 volt service drop configured? Was it a 2-wire 480-0 single ended system, or an Edison-style 240-0-240 3-wire system at twice the voltage single phase is normally supplied at? Was the ground/neutral of the secondary side of the customer dry transformer connected to the one ground+neutral wire of the service drop? Did they do this with one pole transformer, or two?
If the grounded conductor of the 480 volt service drop was not connected to the derived 120/240 system, then I'd say the MV currents on the MGNs were the original problem. But if that connection is present, then I'd say that the original problem was that the 120/240 system itself was the problem through the fact that it had a MGN of its own (one at the transformer, and probably sharing all the MGNs of the MV circuit, too, and one at the service entrance. This can create a ground return on the LV side, even through the MV circuit itself.
It's sad that a utility has to go around making such claims. I'm sure it's typical corporate greed and hoping the complainer will just go away so they don't have to deal with it. But this is a well know problem that exists all over the country. I'm sure the utility knows about it, but hopes they can just blame the farmer for their own issues (which in fact at times really is the cause).
Do you remember if the MV circuit was single phase or three phase?
| I said all of that to say that isolation from the utility's MGN is | sometimes a very good idea. All that went down over twenty years ago. | It is true that modern practice calls for an equipotential plane in the | floors of stock barns but it is also true that the stray current does | not always originate in faults in the premise wiring.
There are so many places for electricity to go. It will find them _all_ given the chance.
And was that 480 volt tariff just for farms, or was it available in other places? If I'm going to put in a transformer, I think it would be a better idea to use 480, if I can get it.
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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snipped-for-privacy@ipal.net wrote:

I no longer recall what the MV supply configuration was. The output side of their transformer had two fully insulated bushings. There was a case connection but only the MV MGN was attached to it. The tariff was for any customer who had a long run of private service conductors. This was the only tariffed service that did not include a grounded conductor. I don't know if the tariff was actually intended to supply ungrounded service but the fact that it didn't forbid it was good enough for me.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
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| No, I don't share your motivation and may we may share a lack of a solution. | | I believe that the problem in the dairy industry was the so called stray | currents. Considering that such currents, of a higher magnitude, can be | produced from the LV system, additional, smaller currents from the MV system | may not be the problem. I once read a book which dealt with this and this | contained a detailed technical analysis which brought the concept of ground | currents from MV systems into question. A greater problem was poorly | maintained LV wiring. However technical opinions and legal opinions are two | different things.
Given a constant resistance, MV is going to push current harder than LV. Certainly in many cases it can be an LV issue. When it is, it is easier to deal with and get fixed. But when it is an MV issue, then it is a lot harder to get fixed. Perhaps more initial incidents might be from an LV based cause. But those caused by MV persist longer because the utilities tend to not want to take the steps to fix it.
| If the MV system is grounded properly, there will be unbalance ground | currents-true. A separately grounded LV system, including one using your | isolation scheme will have much higher ground currents and, since the earth | is a common conductor, there will still be coupling between MV and LV ground | systems. Rather than isolate or try to do so, it might be better to spend | money on ground rods- even a ground grid and tie everything to this grid.
This depends on where the return point on the LV system is. If the system is derived at a pole transformer, which will be grounded, then there will be two return paths, the neutral of the service drop and the ground itself by means of neutral current flowing over the neutral to ground bond, to the entrance based grounding electrodes, and through ground to the pole grounding electrode, and up the pole grounding wire to the transformer.
The problem is the system has multiple points of grounding the neutral. The NEC doesn't allow this and for good reason. The NESC forces it on the service drop.
The fix is to derive an entirely new system with a transformer where the primary is connected to the two line wires at 240 volts for single phase or delta for at 208 or 480 volts for three phase. The neutral on this system will have exactly one bonding point (unlike the service drop system that has at least two). As long as there are no faults in that system, then any neutral currents can only flow back to the source by means of the neutral conductor. Even if the service drop neutral/ground wire is connected to the secondary bonding point (e.g. all grounds/neutrals are connected together), it introduces no additional paths on the secondary system because the secondary neutral has exactly one point for it to reach ground (even though after that point is then can branch out to get to ground by the electrodes at the building and through the service drop neutral to the pole grounding electrode).
However, this doesn't prevent any MV current from coming down the neutral and flowing through the building grounding electrodes, unless the primary is fully isolated (not even ground connected) from the secondary.
| Note that in HV substations a grid is used in order to make the ground as | nea an equipotential as possible and the fence is either outside the grid | far enough to have a low step potential in case of a fault or inside by a | distance such that anyone or anything outside and touching the fence is well | within the grid. This is a bit extreme but the same idea of an equipotential | grid to which all neutrals, enclosures, etc are connected may be a better | alternative for locations considered critical. This will mean that the | ground under a cow is at the same potential as the milking machine hardware | attached to the udder. Your isolation scheme doesn't do this.
I don't know if they do this, or not, but the milking machine could be made to work where there is absolutely no metal contact to milk where the milk flow is continuous back to the udder. This isn't hard to do, so I want to believe they have done this.
Still, this doesn't address the fact that these problems exist outside of the scope of milking activity. Apparently some step potential exists near any point of grounding electrode that has a metallic path back to an MV circuit. Apparently livestock can sense it, at least when standing or walking bare-hoof on at least wet ground. MV neutral currents flow out each grounding electrode and radiate outward from there.
If I were a dairy farmer, I would at least isolate the milking operation, which is where the livestock would be near grounding electrodes and when their sensitivity would have a significant impact. I don't know offhand what kind of power they need. But a plastic natural gas pipe, or a propane tank, connected to a generator, might do the job. The area might still need a ground ring to divert any exterior ground currents passing by. Or maybe I could "go green" and power everything from solar power sources. Or maybe from indigenous methane :-)
Adding a transformer at the end of a service drop I do think will improve things (because of the singular bonding). It's not all I want, but it is more than most have.
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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snipped-for-privacy@ipal.net wrote:

As Tom alluded to, buildings for livestock have to have equipotential floors - mesh or other conductors in the concrete floor connected to the building ground system. That should take care of the stray current problem in buildings. Stray currents could still be a problem outdoors (if the livestock can go there).
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| snipped-for-privacy@ipal.net wrote: |> |> If I were a dairy farmer, I would at least isolate the milking operation, |> which is where the livestock would be near grounding electrodes and when |> their sensitivity would have a significant impact. I don't know offhand |> what kind of power they need. But a plastic natural gas pipe, or a propane |> tank, connected to a generator, might do the job. The area might still |> need a ground ring to divert any exterior ground currents passing by. Or |> maybe I could "go green" and power everything from solar power sources. |> Or maybe from indigenous methane :-) |> | As Tom alluded to, buildings for livestock have to have equipotential | floors - mesh or other conductors in the concrete floor connected to | the building ground system. That should take care of the stray current | problem in buildings. Stray currents could still be a problem outdoors | (if the livestock can go there).
The usually can go outdoors.
Which is more expensive, the equipotential floor (including cost of installation and disruption of operation) or the ungrounded service (and its cost of installation)?
What I want, though, is for there to be no MV system currents on my grounding electrodes whatsoever. I don't want the added corrosion. I don't want the added induced hum. I don't want the intermodulation with my RF fields. And I just don't want it for the principle of the thing.
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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snipped-for-privacy@ipal.net wrote:

May be rather limited in factory farms. If outdoors, maybe cattle orient up to minimize voltage between front and back of animal, and might be the equivalent of iron filings in a magnetic field. ;-)

In new buildings, which is what the NEC applies to, an equipotential floor shouldn't cost much.
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wrote:

---------- If the MV side of a transformer is connected line to ground and the LV load is perfectlybalanced, then there definitely will be a higher neutral current in the MV system. Consider a 7200/240/120 transformer. If the load is 2.4KVA at 240 V the secondary current is 10A and the secondary neutral current is 0. The primary current will be 0.33 A and the primary neutral current will be 0.33 A. This assumes negligable ground resistance but for a 100 ohm ground rod resistance the neutral to true ground voltage will be about 30V. Now consider that the secondary load is 120V 7.5A on one leg and 120V, 2.5A on the other leg. Secondary neutral current will be 2.5A while primary neutral current will be about 0.2A. Which dominates? Even at 1.3KVA on one leg and 1.1 KVA on the other, the secondary neutral current will be about 1.7A while the primary is still nearly 0.33A. If the load is essentially 240V or very well balanced between legs of the secondary, the secondary neutral current will exceed the primary current. However, a factor that exists is that there may be downline loads which produce MV neutral currents. This could be of concern. -------

-------- Fair enough- I indicated as much. ---------

------
---------- This implies an ungrounded primary except possibly back at the main substation neutral point. Either line to line or line to neutral (neutral grounded at onl one point-the main sub). If main sub doesn't have a ground point- then the line is floating. For distances measured in feet or even a few miles at MV , this may not be a problem except for protection purposes. Otherwise, we are back to the reasons why delta transmission is not used. Viable- yes- within limits- advantages- maybe, maybe not.

------- Any I have seen don't have such a contact. ----------

--------- Much of what is going to happen is dependent on a: location of the line with respect to the region of concern. While currents do radiate out from grounding electrodes( and current density and step voltage drops decrease rapidly), AC currents will tend to follow the line. This could mean that the problem is not due to local circumstances but due to what is going on downline. However, as Tom states, going to a 4 wire system did eliminate 3A , use of a higher voltage transformer at some distance from the farm, and stepping down eliminated much more "stray current". This may not always work as the source of the current may be elsewhere. Adding the transformer at the service drop may well be the answer- if the service drop is far enough away but other factors come in.
--

Don Kelly snipped-for-privacy@shawcross.ca
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snipped-for-privacy@ipal.net wrote:

If you can get the utility to install a transformer without a grounded secondary then your home free. Such installations are usually unavailable. There is no particular danger in using such a supply to feed a dry transformer because that supply would be ground referenced at the next transformer or several spans away at the worst. It's just that if that kind of service is not identified as an available form of service in the tariffs of your states utility regulatory body the power utility will not provide it.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
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On Fri, 27 Oct 2006 02:22:08 GMT Member, Takoma Park Volunteer Fire Department
| If you can get the utility to install a transformer without a grounded | secondary then your home free. Such installations are usually | unavailable. There is no particular danger in using such a supply to | feed a dry transformer because that supply would be ground referenced at | the next transformer or several spans away at the worst. It's just that | if that kind of service is not identified as an available form of | service in the tariffs of your states utility regulatory body the power | utility will not provide it.
I know they don't like to provide it because that means the transformer they are responsible for is more subject to damage due to ground voltage differential, such as from electrical storms (and not just from a strike of lightning, but also from the ground charge that follows storm cells).
But I do suspect a transformer designed for MV circuits will have better insulation levels between primary and secondary, and so could survive a case where a LV-to-LV dry transformer might not. OTOH, I absolutely do not want the utility to supply me power above 600 volts. If I were to take the approach of a full isolating transformer, using a pole pig to do it might be more reliable. But I'd have to take power from the utility at LV then step it back up to MV again on my own (e.g. the disocnnect would be at the LV service drop). Just imagine two yard poles with pole pigs on each and they are coss connected to each other. I saw a couple of nice 14.4kV 15kVA dual bushing ones a year or so ago. I even thoght about buying them. I don't mind having MV coming across my property as long as I personally have access to cutting it off with a LV disconnect with lockout.
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Continue from where I left off...
Schuko is not bad, but it has one major disadvantage; it is unpolarised. This is not advisable with things like ES lamp sockets; though I think their days are numbered, I wouldn't be surprised to see them banned in Europe for new installations within a few years, for both safety and energy effienciency reasons. It's already a requirement that new buildings, or reburbished ones, have a certain proportion of lamp fittings that cannot take traditional incandescant lamps.
Plug design is one area where Europe got it badly wrong. In most of Europe the live and neutral pins are very similar in size and spacing. they are not identical, some are 4mm diameter, and some are 4.8. Some are at 19mm spacing, and some are something slightly different. To get around this problem the two-pin 'Europlug' was devised; it has two thin pins which are angled inwards slightly towards the tips. they are shrouded. The pins can bend slightly in the plastic moulding, the idea being that they can fit most European three-pin sockets. The problem is that it fits all of them badly, and is restricted to a low current, I think it's either 2.5 or 3A. I don't like this, I'd rather see standard sockets, and plugs that fit them properly. When you go to the 3-pin plugs they do dit properly, and can handle the full 16A load, but there are lots of different versions. There have been several attempts at standardisation, but agreement could never be reached. One suggestion was to abandon them all, and design something totally different. You'd better get that drawing of your design ready! Germany has the Schuko, with its top and bottom earth contact strips, France has something similar, but the earth contact is a pin in the socket which fits into a hole in the plug. Most Schuko plugs have such a hole, so they can be used with either type of socket. They are polarised when used in the French socket, but not in the German one. Italy uses something like a Europlug, but with an extra pin between the other two, and in line with them. This is also unpolarised. If you take this, but move the earth pin slighly upwards, to form a low, wide triangle, you get the Swiss one, which is polarised. Most of the other countries use one of thesetypes, except Demarrk, which has its own unique design, with strangely shaped pins. What a mess. I wouldn't recommend any new system to follow the European route.

that I'm not a great fan of the NEMA range. I think there are several problems with them:
There are too many of them, though this is not a problem with the connectors themselves, but simply reflects the number of different types of supply in America.
There's not really a logical pattern to them; you can't tell just by looking at an unfamilar connector what it is intended to be used for.
The vast majority, though not all, of the receptacles are unshuttered.
The blades are too thin; some of the poorer quality ones are quite soft, and bend easily. The metal is too thin to allow shrouded blades to be used. With a bit of effort I can just about touch the blades of a NEMA plug at the piint where they make contact; I doubt that I could do so accidently, but a small child certainly could.
Another problem, though again not the fault of the NEMA design, is that many of them are of very poor quality; there are good ones available, but there's also a lot of absolute junk. I find that if you speak to an American about this you generally get one of two responses; either
"The higher quality receptacles cost about a dollar more" This is for the better domestic grade, not the industrial grade ones. So what, that would add maybe $100 to the total cost of a house, hardly a major increase; isn't it worth it?
The other response is: "The cheap ones are good enough, they do the job" I'm sorry, but in my book a plug or socket which gets distinctly warm, if not downright hot, when carrying well under its rated current, or where the pins are obviously burned is not 'good enough'. I'm not a great health and safety fanatic, I think a lot of today's regulations go too far, but some of these things really are a fire hazard, and shouldn't be on sale. Fifty years ago we had a lot of equally bad stuff here, but we've got rid of it from the shops long ago, and you seldom see any still in use.
So, I'm really not totally happy with any of them. I'm not too worried about the shape of the pins; I'd like them to be nice and solid, with a large contact area, shuttered sockets, or at interlock so that the socket cannot be live when there is no plug inserted, shrouded pins, or other means to prevent partially-inserted pins from being touched. I think you could bring the pins closer than on post of the existing designs, to reduce the overall size.
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On 11 Oct 2006 11:41:22 -0700 snipped-for-privacy@mail.croydon.ac.uk wrote: | Continue from where I left off... | | Schuko is not bad, but it has one major disadvantage; it is | unpolarised. This is not advisable with things like ES lamp sockets; | though I think their days are numbered, I wouldn't be surprised to see | them banned in Europe for new installations within a few years, for | both safety and energy effienciency reasons. It's already a | requirement that new buildings, or reburbished ones, have a certain | proportion of lamp fittings that cannot take traditional incandescant | lamps.
If by ES you mean Edison Screw ... I've already heard those are banned in some places like Germany, at least for pluggable lamps.
| Plug design is one area where Europe got it badly wrong. In most of | Europe the live and neutral pins are very similar in size and spacing. | they are not identical, some are 4mm diameter, and some are 4.8. Some
My understanding is that Europe was 220/127 before Edison, and the first plug design was based on that, and hence unpolarized because the power was L-L. When electric lights came along, rather than connect them to 127, they connected them to 220. Dangerous. Then my guess is they changed things over to 380/220 for a combination of reasons, like more efficient use of wire, and getting a grounded wire on the screw base shell.
| are at 19mm spacing, and some are something slightly different. To get | around this problem the two-pin 'Europlug' was devised; it has two thin | pins which are angled inwards slightly towards the tips. they are | shrouded. The pins can bend slightly in the plastic moulding, the idea | being that they can fit most European three-pin sockets. The problem | is that it fits all of them badly, and is restricted to a low current, | I think it's either 2.5 or 3A. I don't like this, I'd rather see | standard sockets, and plugs that fit them properly. When you go to the | 3-pin plugs they do dit properly, and can handle the full 16A load, but | there are lots of different versions. There have been several attempts | at standardisation, but agreement could never be reached. One | suggestion was to abandon them all, and design something totally | different. You'd better get that drawing of your design ready! | Germany has the Schuko, with its top and bottom earth contact strips, | France has something similar, but the earth contact is a pin in the | socket which fits into a hole in the plug. Most Schuko plugs have such | a hole, so they can be used with either type of socket. They are | polarised when used in the French socket, but not in the German one. | Italy uses something like a Europlug, but with an extra pin between the | other two, and in line with them. This is also unpolarised. If you | take this, but move the earth pin slighly upwards, to form a low, wide | triangle, you get the Swiss one, which is polarised. Most of the other | countries use one of thesetypes, except Demarrk, which has its own | unique design, with strangely shaped pins. What a mess. I wouldn't | recommend any new system to follow the European route.
There was no EC back then. Everyone was on their own. So development went in crazy ways. There were some historical plugs with crazy designs even in the USA. Fortunately, those disappeared.
|>From what I've said earlier, you probably won't be surprised to hear | that I'm not a great fan of the NEMA range. I think there are several | problems with them: | | There are too many of them, though this is not a problem with the | connectors themselves, but simply reflects the number of different | types of supply in America.
Exactly. I have the document that describes them all. Overwhelming. I'm trying to make web construct images of most of them. Some of that is already seen in some URLs I have shown.
| There's not really a logical pattern to them; you can't tell just by | looking at an unfamilar connector what it is intended to be used for.
There was a little bit of logic in a few. But as it expanded, logic got lost. That's probably because no one who had vision also had the power to make it happen.
| The vast majority, though not all, of the receptacles are unshuttered. | | The blades are too thin; some of the poorer quality ones are quite | soft, and bend easily. The metal is too thin to allow shrouded blades | to be used. With a bit of effort I can just about touch the blades of | a NEMA plug at the piint where they make contact; I doubt that I could | do so accidently, but a small child certainly could.
Yes, there are thin bendable blades around. But I also have many that are solid and sturdy. I would go a bit thicker, maybe as much as the blades in the BS1363.
| Another problem, though again not the fault of the NEMA design, is that | many of them are of very poor quality; there are good ones available, | but there's also a lot of absolute junk. I find that if you speak to | an American about this you generally get one of two responses; either | | "The higher quality receptacles cost about a dollar more" This is for | the better domestic grade, not the industrial grade ones. So what, | that would add maybe $100 to the total cost of a house, hardly a major | increase; isn't it worth it?
Contractors and speculators build homes under the principle of "cheapest everywhere". Maybe they save only $100 on receptacles and switches. But if you add that up for all the other things they go cheap on, it can add up to thousands of dollars of savings. If there is an argument why they should not go cheap, wouldn't it apply to the whole house?
| The other response is: "The cheap ones are good enough, they do the | job" I'm sorry, but in my book a plug or socket which gets distinctly | warm, if not downright hot, when carrying well under its rated current, | or where the pins are obviously burned is not 'good enough'. I'm not a | great health and safety fanatic, I think a lot of today's regulations | go too far, but some of these things really are a fire hazard, and | shouldn't be on sale. Fifty years ago we had a lot of equally bad | stuff here, but we've got rid of it from the shops long ago, and you | seldom see any still in use.
UL should be testing them. I don't know how that is working out.
| So, I'm really not totally happy with any of them. I'm not too worried | about the shape of the pins; I'd like them to be nice and solid, with a | large contact area, shuttered sockets, or at interlock so that the | socket cannot be live when there is no plug inserted, shrouded pins, or | other means to prevent partially-inserted pins from being touched. I | think you could bring the pins closer than on post of the existing | designs, to reduce the overall size.
My thought was 4mm to 6mm spacing for the lower voltage I proposed, and 10mm to 15mm for the higher voltage I proposed, at the 16 amp level.
I've also thought about the idea of using a coaxial pin construction where the end of the pin has the hot contact, and the sleeve has the grounding/earth contact. The opening would have the grounding wire contacts completely blocking the opening, effectively being the shutter. Both pins would be this way so there would be 2 connections of ground. The tip of the pin would have to break from the contact for power as it is removed, before it reaches the grounding shutters. Maybe this would be a good design for the lower voltage plug. It would still be possible to push the shutters open by sticking something in, but at least if the hot contact is made inside, it is likely that whatever does contact it is also grounded at the shutters that are squeezing on it.
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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snipped-for-privacy@ipal.net wrote:

Some of the replacement, low power consumption lamps, still come with screw bases.

In spite of its shortcomings, the ES was one of the great inventions of its time. Early lamp bulbs had to be "installed" by crews of boys on bicycles, who brought replacement bulbs to customers.
The screw vase was cheap, low tolerance, provided both electrical and mechanical interface, and could be used by anyone without tools. There was the story of a farm wife, whose house had just been wired, and was asked how she liked the new lights. She answered, "The light's fine but I burn my hands taking it from one room to the other."
(How many programmers does it take to change a lamp bulb?) ;-)
Lamps were an early example of the "Gillette plan", where you give away the product and make a good profit on the consumables. (Now the HP or Epson plan.)
My family lived in Saint Louis in the early thirties. The power company would regularly raise the voltage to burn out "old" lamps. They would give free replacements, which used more power than the old ones.
You can get printers, almost free, that way now! :-)
--
Virg Wall, K5EVE

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Just came back from Iraq, the electrical work there is a nightmare. The cords they are using on the 220 are so thin, I have seen where the insulation on the cords that are in a bundle melt together, and eventually short together. The actually plugs are so flimsy that your plug does not fit in sung, but kind of moves around in the receptacle. Saw a few electrical related fires there. The guys that are working for KBR and the military electricians are trying to keep up with the demand, but using existing house wiring there exposes just how bad the electrical work can be done. Dont even get me started on how bad the grounds are in the Iraqi buildings that we were using for our electronic equipment. It was easier to make our own halo and drive stakes and redo the ground. Pretty much if you plugged into an iraqi wall jack, the equipment would shock you.

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| Just came back from Iraq, the electrical work there is a nightmare. The | cords they are using on the 220 are so thin, I have seen where the | insulation on the cords that are in a bundle melt together, and eventually | short together. The actually plugs are so flimsy that your plug does not fit | in sung, but kind of moves around in the receptacle.
If they even use plugs. I've seen pictures of homes there where they just jam the wires into the socket. Those eurosockets seem to be just the right size for that.
| Saw a few electrical related fires there. The guys that are working for KBR | and the military electricians are trying to keep up with the demand, but | using existing house wiring there exposes just how bad the electrical work | can be done. Dont even get me started on how bad the grounds are in the | Iraqi buildings that we were using for our electronic equipment. It was | easier to make our own halo and drive stakes and redo the ground. | Pretty much if you plugged into an iraqi wall jack, the equipment would | shock you.
Did you ever see that TV show on PBS Independent Lens series covering the US company that ran the power company in the former Soviet Republic of Georgia? In one segment they went out to an large apartment building that was built in the Soviet era but never occupied at that time. Squatters moved in and hooked up their own power by running wires straight down from whatever floor to the transformer building nearby. One guy mentioned a neutral that was way too hot. Another mentioned faults further into the building he could hear, and was afraid to venture any further in. It was quite a show. The company ended up having to pull out, not being very successful selling electricity to people that were accustomed to having it provided free by the government (which also used to be the case in Hussein's Iraq).
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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Got news for you. The Valdez Marine Terminal at the end of the Trans Alaska Pipeline has about fourteen miles of cable tray installed in 1975-76 under the supervision of Fluor Daniels Engineering. The cables in the cable tray have no grounding conductors - that's right none!
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Dana wrote:

I realize this is not really the topic for this newsgroup, but.... There are good union and nonunion electricians and shops. I just think it is a better deal for the electrician to have a good retirement where the pension benefits follow the electrician. The IBEW now has reciprocal agreements amongst different locals. In other words if a IBEW electrician works 10 years out of one local then works in other locals he can have all his pension benefits sent back to his home local. Since so many electricians have to move around to stay employed this is a real advantage. It is true that a nonunion electrician can do similar acts but it requires individual accounting and control of funds than most do not have time for. The IBEW employs persons that work full time for the members and that is worth being a member on its own merits.
Many Union electricians came from nonunion shops. I have seen some really great electricians that came through the IBEW apprenticeship program. But I have also worked with some really great electricians that came from nonunion shops. Being great means good with the tools, a good mechanic, but mostly good to work around and for because they have a good attitude.
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