Return-Path: Received: by massis.lcs.mit.edu (8.7.4/NSCS-1.0S) id KAA06601; Mon, 9 Dec 1996 10:08:34 -0500 (EST) Date: Mon, 9 Dec 1996 10:08:34 -0500 (EST) From: ptownson@massis.lcs.mit.edu (TELECOM Digest Editor) Message-Id: <199612091508.KAA06601@massis.lcs.mit.edu> To: ptownson@massis.lcs.mit.edu Subject: TELECOM Digest V16 #655 TELECOM Digest Mon, 9 Dec 96 10:08:00 EST Volume 16 : Issue 655 Inside This Issue: Editor: Patrick A. Townson In a Power Station During a Blackout (Darryl Smith) Re: Modems in Countries Other Than North America (Dennis Wong) Re: Tormenting Telemarketers! (Geoffrey Welsh) Re: Competing Local Telecom Providers: How's it Work? (Art Kamlet) Re: Competing Local Telecom Providers: How's it Work? (Wes Leatherock) Re: Dialing Software and Areacode Overlays (Linc Madison) Re: Replacing a Cell Phone (Linc Madison) TELECOM Digest is an electronic journal devoted mostly but not exclusively to telecommunications topics. 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A suggested donation of twenty dollars per year per reader is considered appropriate. See our address above. All opinions expressed herein are deemed to be those of the author. Any organizations listed are for identification purposes only and messages should not be considered any official expression by the organization. ---------------------------------------------------------------------- Date: Sun, 08 Dec 1996 18:30:52 +1000 From: Darryl Smith Subject: In a Power Station During a Blackout Pat, Below is a message I got and a reply on the ethernet, powerstations etc. darryl smith > Dan Foster wrote: > In article you write: > >problems. (You should be in a power station during a blackout :-) > :-) > Fascinating article you wrote. > But to ask about more mundane things - out of sheer curiosity, what *is* > it like to be in one during a blackout? :) What kind of activity goes on > to restore power, if you know? > -Dan Foster > Internet: dsf@frontiernet.net OK well ... In February this year I was up at Bayswater (In the Hunter Valley in NSW Australia) and I was in the electrical section - OK - I was the electrical section - almost - I was straight out of uni. I had an electrical engineering boss who came with the power station and will leave if it ever gets shut down; but not before; and a technical officer who was an expert in power systems protection. And we had a uni student on a semester's work (Known as a cadetship). Power Stations are a place which can be very expensive to repair if things go wrong. Think about 200 tonnes of metal spinning at 3000 RPM and then put a turbine on the end. That is the size of thing I am talking of. And the generator is filled with Hydrogen gas to improve its efficiency in cooling (650 MWatts capaity becomes 200 MWatts in air). To keep the hydrogen high pressure oil is pumped onto the spinning shaft at each end to keep the air out, and then the oil it put in a vaccuum to remove the water and oxygen from the oil. Oil is also used to cool the bearings; which get quite hot given the weight of the generator rotor - and the bearing at one end is insulated. IF the bearings get to hot, they melt, causing a short circuit between the rotor and the shaft; and you have a spinning metal in a magnetic field and get the case magnetised (The case is iron and weighs over 100,000 Kg). Demineralised water is used to cool the hydrogen in the generator, and insode the copper conductors in the stator (After all a generator is only 99 % efficient that means that 6.5 MWatts of heat is produced !!!!!!) In addition there is a boiler which is about 11 stories tall with various cameras inside at US$500,000 each which need constant cooling or else they will burn ... All the important stuff like oil pumps, cooling pumps etc are all DC motors. And we have two of any important motors, fed from different switchboards, and usually different batteries. By usually I mean that is the normal case. Sometimes we need to take a battery bank out - and have both switchboards supplied from the same battery. But each battery is constantly on charge from a battery charger/ DC supply. These chargers have an automatic changeover if they lose supply from their primary AC switchboard. So for the 11kV system there are: Unit A and B switchboards (with incoming supplies from one of two locations) and able to be connected in the center. Station A and B switchboards in a similar configuration. In terms of DC we have the same sort of thing running on 24, 50, 110 and 240 Volt DC batteries. Back to February this year - my supervisor was off for the day (we have a 9 day fortnight) and had just rung up to make sure nothing had gone wrong. Of course not. That would happen when he hung up. The Technical officer had just left the building too. And I was plant owner for switchboards - The expert. (I was also plant owneer for motors and DC Systems - My boss had Transformers (He has blown up more 400 MVa transformers than anyone else in the country and the generator circuit breaker.)) The lights in the admin building went dark. Once they didnt return after a few seconds I grabbed a torch and the cadet along with the hard hat and raced to the admin switchboard. When I got there one of the management was there looking what went wrong - He told me the incoming supply had died; and told me where the switchboard was that supplied it as I didnt know ... I was the second person to get to the room - And the room was dark except for two tiny 12 volt 6 watt fluro lights for a room over 10meters by 25 meters - The emergency lighting inverters were on the sections work list - but they were not a real high priority as some other work. One of the assistant power plant opperators (APPO's) tried to determine what had happened. Luckilly the protection technicican cam in soon and we were able to work it out. By this stage I told the CADET to get the logs for the power system (they show up any disturbansecs to the power system including timing diagrams and waveforms). We worked out that the new ash disposal system had caused the switchboard to trip. - But why? Everyone decided to go to the control room at this stage - which was packed. The manager was there as were a lot of extras hoping that their training on the power plant simulator was affected by the blackout they would play with the real thing. The auxillary computer was out of action due to the power failure - The main computer was running but not all information went to it. The computer was down cause the UPS had failed (40 kWatt UPS running off 240Volt DC). At this stage the station is still running at full load (650 MWatts). we then worked out what had happened. The ash disposal system was very new and placed onto above ground cable trays to get the wiring to it. And these are 3 * 2 inch 11KV cables for about a mile. It was supplied from the 1/2 and 3/4 end of the power station by seperate cables. The 1/2 end was supplying the current to the switchboard the people at the other end were wanting to work on. So they opened the circuit breaker to the switchboard - leaving the breaker from the 3/4 end able to be remotely closed at ANY time. Then they short circuited the incoming supply on the LIVE side. This caused the switchboard to trip itself to protect itself. Then they started work. They didn't hear the big bang which was produced when they closed the short. Back in the control room people mentioned hearding a bang, and us experts though the circuit board might have been damaged. To protect anyone doing work - all woork must be isolated including outgoing supplies with a visible break that much be impossible to electronically bypass - and all this work must be verified by someone before any work can be done, and each person going into the area needs to be signed in and out; with everyone out of the area before power can be applied. There were problems opening up this switchboard since we needed to isolate the circuit which had been short circuited as no one wanted to rely on them to correctly do anything.And then an alarm went off. One of the large motors (8 MWatt 47,000 KGram) tripped for an unknown reason. The reason would have appeared on the computer which was out of power. No this motor was very important (Known as an ID fan it sucked air out of the boiler so that power production went down to 400 MWatts meaning a large decrease in income (US$30 / MWatt hour means that about $10,000 is lost each hour that we are not operating). So there were now two problems we had to face. A) Could the motor be put back into service (it's cost was about $10 million and the spare was off site anyway) b) Could the switchboard be put back into service. The technician and I decided to get into the back of the 11 KV switchboard - against our safety rules - leaving the cadet in the control room incase any one decided to do anything stupid, and so our lack of presence would not be known so much. On opening the switchboard we found no problems which was very good - and we stayed away from the high voltage conductors all the same. Still we needed to officially test the switchboard - And it took 18 hours to get the board isolated so it could be tested and looked at (Finding nothing). The decision having seen inside the switchboard was to test it and put it back into service as soon as we could. With the motor we decided that the computer should be brought back on line first. When it came back we found that what had caused the problem with the motor was an oxygen sensor that had last power when it should not have. It told the computer that there was not enough oxygen in the boiler, so it told the fan to change the angle of the blades on it's fan so that it was not extracting the oxygen. This caused the motor to overheat and the protection took it out. We decided that since the motor was probably un-damaged, and that no more damage would be done re-starting it we may as well re-start it - which we did. That was ok. By this time it was 4:00 in the afternoon and time to go home. On the next day (Tuesday) after getting the switchboard back in service after testing (except for the circuit to the ash system) it was found that the cable to the ash system has shifted. The each of the 3 conductors were held together by clamps every 3 feet; and each cable was 2 inches in diameter. Between clamps the cables had pushed away from each other so that in the middle they were about 2 inches apart. This for the mile of the tranmission line. During the short, the cable moved, hitting the cable trays causing a big BANG. And you might think the story finished there - on the Thursday whilst I was in the weekly team leaders meeting telling the manager that things were back to normal there was another blackout - although this was less serious. In this casse a link on a current transformer was not closed correctly, causing the same switchboard on the 3/4 end of the station to trip. ------------------ Ok - To finish off - What goes into restoring power in a power station ... well power stations are an amasing place - and consume a lot of power. For instance the starting current required for the ID fan which failed in the above story is 80 MVa (80 MWatts) which is more than is used by many small cities. And it pulls this for 5 minutes. So if the entire eastern Australia looses power we start a Gas turbin from battery power; We then start an ID fan motor; then the smaller motors that are needed and then start up the boiler etc etc etc. Once the power station is operating there is a constant load of 40 MWatts for various equipment. The Gas turbine can only just supply one 650 MWatt unit. Once it is started other units can be started from it. But power stations take a long time to heat up. It might take 2-3 days if the water has got cold in the boiler. it is not uncommon to take hours to come on line. Once things are synchronised, you can only increase generation in 3-5 mwatts per minute; which takes a while to get to full power - and then when you get over 100 MWatts it is slower as you then turn off the oil and run on coal. And for a black start many switchboards need to be set up so that they are providing power to exactly the right place. This would take more than a day to design before you could even attempt to start any part of the station. These stations have 60,000 drawings and many more manuals; and are over 600 meters from one end to the other without cooling towers (In other words the building only). ----------------------- And finally the DC systems - 200,000 KGrams of lead-acid batteries are used. They are on the top floor of the electrcical services centre above the technichians area and computer room - and the floors leak ... Darryl Smith ------------------------------ From: Dennis Wong Subject: Re: Modems in Countries Other Than North America (US & Canada) Date: Sun, 08 Dec 1996 22:21:51 -0800 Organization: MIND LINK! - British Columbia, Canada Reply-To: a15283@mindlink.net Nils Andersson wrote: > In article , bkron@netcom.com (W > Halverson) writes: >> Fortunately, DTMF tones are universal. > At least they did something right. Just about everything else varies, for > example: > 1) Dial tones. Ever heard a british "humming" dial tone The dial tone in some PBXs (the Cheap ones) are even more bizarre, they sound like the Sprint calling card tone (call 1-800-877-8000 and you will see what I mean). Also, the dial tone in China (Mainland) also sounds like the sprint calling card tone. > 2) Ring tones. The ring every six seconds is the international standard, > but with many variations. The British "burr-burr" every 3.3 seconds or so > is the most bizarre example. (Singapore and maybe other ex-British > colonies [NOT US or Canada] use the the same burr-burr). Some Mitel PBXs also have the "burr-burr" tone. In Hong Kong the ringing tone has a frequency much like the North American ringing tone,EXCEPT it has a "burr-burr" pattern much like in the U.K. The ringing tones in Singapour, Australia, and India also ahve a "burr-burr" pattern, except it has a higher frequency than the tone in the U.K. In most European countries (except U.K.), Asia, South America, and Africa (except South Africa), the ringing tone sounds like a single 400Hz tone that goes 2 second on, and 4 second off. > 3) Busy tones. Fairly standard, I think. Comments anybody? The busy tones in Hong Kong are the same as in North America. In China, the busy tone sounds like the inturrupted Sprint Calling Card tone (0.5 seconds on, 0.5 seconds off etc.) ------------------------------ From: crs0794@inforamp.net (Geoffrey Welsh) Subject: Re: Tormenting Telemarketers! Date: 9 Dec 1996 07:13:03 GMT Organization: Izot's Swamp On 27 Oct 1996 11:14:01 -0500, in comp.dcom.telecom, glnfoote@freenet. columbus.oh.us (Glenn Foote) wrote: > The supply of replacement telemarketers will always exceed the demand. ... as will the supply of criminals and diseases. I refuse to condone any of the above, no matter how inevitable. > Telemarketers come from _all_ backgrounds ... including some which are > outright criminal in nature. Some (note: _some_ , not all, or even many!) > are capable of violence. Few, if any telemarketing companies do even a > routine background check. ... which is just one more reason why we should do everything we can to make telemarketing an unprofitable business. > The gathering (and selling) of lists containing your phone number will > increase. These lists include many things _in addition_ to your phone > number. Like your address(s)! ... which is just one more reason why we should do everything we can to make telemarketing an unprofitable business. > Telemarketing _is_ legal. If you don't like it you should work to change > that fact, but for the time being you will have to live with the issue. Drugs and many other things are illegal, yet they continue because they're profitable. Where in the crime-fighting priority list do you think telemarketing would fit, even if it were banned outright?!? There is only one way to make telemarketing go away: make it unprofitable. The 'nicest' way to do this is for everyone to stop buying anything pitched over the telephone, but there will always be some poor sucker. I think of myself as the balance to that person. Keep in mind that the caller always has the option of hanging up if/when they realize that I'm wasting their time; I'm not exactly keeping them prisoner and, more importantly, I intend to continue conducting myself as if calling the telephone in my house were like knocking on my door. > The people who are calling you _are_ within the law (usually). They may > not like the work they do (but it _is_ honest and legal work), no matter > what you think of it. They have an excuse, and a legitimate reason, for > their behavior. Unh-hunh. And my neighbour has an excuse and a legitimate reason for spreading strongly scented manure on his lawn weekly, but that doesn't mean I have to be nice to him in return. Geoffrey Welsh, MIS Co-ordinator, InSystems Technologies (gwelsh@insystems.com) At home: xenitec.on.ca!zswamp!geoff; Temporary: crs0794@inforamp.net ------------------------------ From: kamlet@infinet.com (Art Kamlet) Subject: Re: Competing Local Telecom Providers: How's it Work? Date: 9 Dec 1996 02:33:25 -0500 Organization: InfiNet Reply-To: kamlet@infinet.com In article , TELECOM Digest Editor noted in response: > [TELECOM Digest Editor's Note: If they were actually competing, they > would run wire to each premise, install instruments, etc. But as a > matter of fact the 'competitors' have whined so much about it and > claimed Bell had such an unfair advantage that regulatory agencies > have required Bell to allow the 'competitors' to co-locate in the > same central office. In some instances, they do not even bother > with that formality; they just force Bell to sell to them wholesale > at a deep discount so they can resell to the public cheaper than > what Bell does ... In fairness, the Bell companies have pretty much written off large portions of their outside plant including local loops and much of their central office equipment. Pat, are you suggesting that new competitive access providers purchase lots of new equipoment while the RBOCs have written that off (which makes it a no-expense item to them)? Sure, in years past the RBOCs did buy all that, but they also collected tariffs based on that cost. Now they have pretty much agreed with their utility commissions in many jurisdictions that they become basically untied to equipment cost (recovered and unrecovered) and char ge "lower than historic" tariffs. But as depreciation costs and capital costs for that equipment don't show up for the RBOCs, they would for the CAPs. The solutions necessarily are political, and no one should be much surprised when politcal commissions make political decisions. > They cannot accept assignment > of a group of phone numbers which in their opinion 'look funny' > because this would also in their opinion be unfair, so Bell has to > open up all sorts of new area codes so the 'competitors' can grab > thousand upon thousands of phone numbers they will never manage > to assign to anyone in the next twenty years. That's a real issue and since the NANP doesn't seem like anyone will be expanding it anytime soon, (Hey, it did go from N0/1X-NNX to N0/1X-NXX to N0/1X-NXX, but what have they done lately?) maybe some method of charging CAPs and RBOCs for "their" reserved NXX-NXX bandwidth (who charges? who collects?) should be considered. Costs are a good way to control inventory. > They even want to force Bell to include all their listings in the > existing Bell directory because ... well, you guessed it.... Can't help wondering Donneley's wonder CEO, now AT&T's CEO-elect, might have some other ideas about that direction? > technology while the 'competitors' spend the next hundred years or so > trying to catch up. So no, you won't see new wires brought to your > premises in most instances. If it does happen, they will be Bell wires > leased by the competitor to serve you. Wire or coax or fiber would combine well with large data services, movies by phone, etc. But if just voice/data is wanted, wireless solutions would be more cost effficient and also avoid lots of easement costs. Art Kamlet Columbus, Ohio kamlet@infinet.com ------------------------------ From: wes.leatherock@hotelcal.com (Wes Leatherock) Date: Mon, 09 Dec 1996 14:13:22 GMT Organization: Hotel California BBS Subject: Re: Competing Local Telecom Providers: How's it Work? In his response to swb@mercury.campbell-mithun.com (Shawn Barnhart)'s posting on how competing local telecom providers work, Pat wrote: > The only thing they have not demanded and been granted thus far is > that Bell be forced to revert to nineteenth century telephone > technology while the 'competitors' spend the next hundred years or so > trying to catch up. So no, you won't see new wires brought to your > premises in most instances. If it does happen, they will be Bell wires > leased by the competitor to serve you. You won't even see trunking and > co-location all that often either. Most of the time it will amount to > nothing more than accounting entries on the books of telco and the > competitor. A lot of the 'competitors' will be little more than > reincarnations of our good friends, the Alternate Operator Services. > The AOS' are essentially bottom-feeders; they serve no useful function > except to charge a lot more than the 'real operators' for their > services. PAT] I saw a story in {The Daily Oklahoman} (Oklahoma City, Oklahoma) the other day that I didn't have time to read fully, but it appeared that AT&T (which is arguing with the Oklahoma Corporation Commission, the regulatory agency) on terms for being a reseller of Southwestern Bell Telephone services as a "competitor" is asking: That when SWBT sends out its employees to do work on their plant serving AT&T customers that they be required to eliminate all Southwestern Bell identification from vehicles, ID cars, uniforms (if worn) or anything else that has SWBT identification on it, because that might confuse customers (my understanding is that the "confusion" would consist of customers realizing their "AT&T" service was still provided by Southwestern Bell). Wes Leatherock wes.leatherock@hotelcal.com wes.leatherock@origins.bbs.uoknor.edu ------------------------------ From: Telecom@Eureka.vip.best.com (Linc Madison) Subject: Re: Dialing Software and Areacode Overlays Date: Mon, 09 Dec 1996 00:10:36 -0800 Organization: No unsolicited commercial e-mail! In article , Christopher Wolf wrote: > Do you or any of your readers know how Win95 users in cities with new > areacode overlays (like 713/281 in Houston) can get their systems to > recognize when and when not to dial a 1 when using the dialing > features built into Win95? There must be numerous people that have > found and addressed this problem -- what's the fix? Well, actually, first of all, 713/281 was re-done as a split instead of an overlay. The boundary roughly approximates the Loop 8 Beltway (Sam Houston Parkway/Tollway), if you're familiar with the Houston area. There are not yet any "general services" overlays in effect, although there are two in Maryland (301/240 and 410/443) next year, and one in Pennsylvania (412/724) in 1997. Area code 917 overlays 212 and 718 in New York City, but it is only for pagers and cellular, at least for the time being. As for how various software products handle the situation, that's a mixed bag. There are a number of complications to consider, based on various local dialing schemes. Take, as an example, a user located in Fort Worth, Texas (without considering yet the split planned for next spring). Some numbers in 817 are local and must be dialed as exactly the 7-digit local number. Other numbers in 817 are long distance (Waco, Wichita Falls, etc.) and must be dialed as 1-817-NXX-XXXX. Some numbers in 972 are local ("metro" numbers, and also other numbers if the Fort Worth user has "metro" service), but others are long distance. The local numbers must be dialed as 972-NXX-XXXX, but the long distance numbers must be dialed with the leading 1. If the Fort Worth user has metro service, then all numbers in 214 are local and must be dialed WITHOUT a leading 1; if she doesn't have metro service, all numbers in 214 are long distance and must be dialed WITH the leading 1. In each case, there is one and only one method of dialing a given number. The way that most software packages account for this is by requiring the user to adopt certain convenient fictions: (1) I have no "home" area code, but I dial "1" as a long distance prefix. (2) Local numbers in my area code are entered as only the 7-digit number. (3) Local numbers in other area codes are entered with the area code field blank, and the full ten-digit number as the local number; e.g., ( ) 972-NXX-XXXX (4) All long distance numbers are entered with area code and number; e.g., (972) NXX-XXXX. Another possibility, based on the example user above, is: (1) Define my "home" area code as 817, with a null "long distance prefix" (2) Define any long distance numbers in 817 as being in area code "1817" (3) Define any local numbers as being in 817, 972, 214, etc. (4) Define any long distance numbers in other area codes as being in area code 1972, 1214, 1202, 1770, 1619, etc. Of course, this all wreaks havoc if the user moves to a location with a different local calling area. The second scheme also causes problems if you are ever dialing 0+; however, it more easily accommodates 10-digit dialing in overlay situations -- just undefine the "home" area code. I do my best to remain completely ignorant of Windows 95 :-) but I'd guess that it takes the approaches above. The only alternative is to keep an up-to-date database of local prefixes in your dialing software, and I doubt anyone does that for a basic application such as you describe. (Of course, the REAL solution is for the telcos in backwards states like Texas to follow the standard, which requires that any call be *permitted* to be dialed as 1-NPA-NXX-XXXX, irrespective of area code or toll status. There is no cogent counterargument against this standard. It does not in any way dilute the protection of "1+ required on toll" in toll-alerting areas.) Linc Madison * San Francisco, Calif. * Telecom@Eureka.vip.best.com ------------------------------ From: Telecom@Eureka.vip.best.com (Linc Madison) Subject: Re: Replacing a Cell Phone Date: Mon, 09 Dec 1996 00:27:46 -0800 Organization: No unsolicited commercial e-mail! In article , arens@ISI.EDU (Yigal Arens) wrote: > [question about upgrading or replacing a cellphone and trying to get the > ~ $300 subsidy again] I was for a while employed by British Rail's Railfreight Distribution** division (which I believe is by now fully privatised), in the office that dealt with mobile phones. In general, as a large corporate buyer rather than an individual, what we had to do was: - buy the phone at a modest discount from retail (reflecting our volume purchasing, but not any subsidy); - commit to a minimum one-year contract for service; - pay off the full value of the unused monthly service fees if the phone was disconnected for any reason, including theft, even if we immediately gave notice and replaced it with another cellphone from the same vendor; I found the third item particularly galling -- the vendor was not losing any revenue from our premature termination of the contract, so there was no justification for the penalty, which often exceeded 200 pounds. All the major vendors gave the same line, though. ** also known as Brutish Rail's Realfright Disturbition Linc Madison * San Francisco, Calif. * Telecom@Eureka.vip.best.com ------------------------------ End of TELECOM Digest V16 #655 ******************************