"Martin H. Eastburn" wrote a delightful piece of science fiction. ^^^^^^^^^^^^^^^^ Don, it pegged my BS meter, as well. Also my entertainment meter. Martin, you are in the wrong forum--this needs to be submitted to Rec.Ent.Sciencefiction.
_I_ only have 208V. not 220, or 240. I've got meter readings to back that claim, *and* utility warning stickers at the meter.
You had better not bet money against that 130v. I used to have a calibrated westinghouse line-voltage monitor that I used wherever I was living.
In one old apartment building (1905 construction) I lived in -- which was less than 70 ft from the substation -- I had a measured 129.5V on the third floor.
Took some _quite_ fussing at the electric utility to get them to send somebody out to check the situation. When the _engineer_ finally showed up, he took one look at the gear sitting on my 'workbench', said "h*ll, you've got better test gear than I do", and radioed dispatch to roll a service truck to the substation 'right now'.
"Robert Bonomi" wrote: (clip) I had a measured 129.5V on the third floor. (clip) ^^^^^^^^^^^^ Gosh! Think how high it must have been on the FIRST floor.
You guys are just not up to speed on custom large factory Production machines.
I have been turning wood since 1957 on and off. Have to turn a handle for the
2" wide steel wrench I cut with my cnc plasma torch. It will be in Walnut.I have been designing electronic and electrical things since before that date. National Science Fair first place winner in 57. That was the weirdest year in my life. Having 3 wings of B-52's in battle dress form up and head East while I was on the play yard.
Yes I have seen it - done it - been there and had it done to me.
The CANCO plant - makes cans from sheet metal - that was or still is in Arlington Tx was the place with this nasty transformer and motor. Three phase normal to nasty.
I think you guys are good in your trade but never ran across this stuff and so it is out of your background.
Ever see a 10,000 amp Ignatron (Mercury tube with an igniter ) They are used to electro plate large metal items - like whole cars or truck bodies. They are getting old now - going to solid state stuff but I bet some are still around.
Martin
"Martin H. Eastburn" wrote: (clip) I think you guys are good in your trade but never ran across this stuff and so it is out of your background. (clip) ^^^^^^^^^^^^^^^ Some of the things I have never seen do not exist.
============================== Technically true, but in practice, a wye primary can be used with a delta secondary allowing, when rectified, a 12 pulse output rather than the 6 pulse of either the dellta/delta or wye/wye. This feature is used in X-ray generators to achieve near DC levels at the X-ray tube.
Ken Moon Webberville, TX.
Like the sound in the forest or the semi-tractor at the 4-way stop ?
There is a lot of things I haven't and won't also. Martin
You just *THINK* you're being a smart-ass. :)
Given the quality of the wiring in the building -- and that I got a measured seven-volt drop at the wall outlet when I kicked on a piece of gear that drew a whopping 8 amps -- I *do* expect the first-floor folks _were_ seeing significantly higher voltages. Simply by virtue of being on significantly shorter runs of that antique 'house' wiring.
I'd really like to know the specifics of the odd things. I really have a fascination for the odd and unusual in the electrical industry.
Don
208V is a common service voltage. You still have 2 120V hot legs to neutral. You find these in apartment buildings, shopping centers, office buildings, strip malls and warehouses, but it would be very rare to have one in a single family dwelling.
This just backs up what I'm saying. 130V in a wall outlet is just wrong. In your case in the apartment building, it was probably a 120/208V service, in which case the problem was the regulator back at the substation. Most times when I see 130V on one hot leg, it's a neutral problem on a 120/240V service.
Don
Martin
I did see the bit about the canning factory in your other post, and dismissed it. The fact of the matter is when your can company or your chrome plating company or some of the companies in my service area, like, Airco, Blue Diamond, and Aerojet, have a problem with the power being served them by the utility, I'm the guy that shows up. Also when the Police call when there's a pole in the road that a car's knocked down, or the Fire Department calls because they want the power shut off to a burning building, or someone calls because they want the power shut off to change their panel or a main breaker, or a little old lady calls that just changed a fuse and her power still doesn't work, I'm the guy that shows up.
I run into a lot of plant mechanics, maintanence workers, maintanence engineers, and various other titles that are responsible for the electrical systems in their plants, and I'd have to say it runs about
70/30 to the ones that have a good understanding of their electrical systems and ones that are winging it. I spend a lot of my time educating the 30% that don't.Don
I used to live in such a building. 54 units, each with two phases run into the apartment (each line of apartments got a different pair of phases).
Ken
I don't doubt that X-ray machines have special transformers in them for their needs. But for distribution transformers a wye primary and a delta secondary is very common, as is a delta primary and a wye secondary. The determining factor on whether the primary is going to be wye or delta is the actual line voltage and the nameplate rating on the transformer. For example, we have a 12KV 3 wire primary that is 12KV phase to phase and
6930V phase to ground. And we also have a 20.8KV 3 wire primary with a common neutral that is 12KV phase to ground. And we stock 12KV transformers. So if you are going to hang a bank in the 12KV primary, it will be delta. And if you hang a bank in the 21KV primary, it will be wye.The determining factor on whether the secondary is going to be delta or wye is the voltage that you want to serve. If you are going to serve a
120/240V 3 phase service the secondary will be delta. And if you are going to serve a 120/208V 3 phase service the secondary will be wye.Note: to serve a 120/208V service we must pull the lids off the transformers and parallel the secondary coils inside.
So by stocking 12KV 120/240V transformers we can use these in both primary systems and serve 120/240V 3 phase, and 120/208V 3 phase and
120/240V single phase.Next week we'll be covering VARS (volt amps reactive) captive reactance and inductive reactance, circulating current, fault current, third harmonic overvoltage, and ferro-resonance. :)
Don
I was cleaning up my new desk - less than half the size of the older "Everlast" I have now in the shop. (All metal with a 1939 floor top.) (has the drill holes for locks and all.) I ran across an old IR - International Rectifier handout - that I generated years ago. I was a great (and still am) fan of IR. Power!
My old version - General information - Silicon Rectifier Circuit diagrams - Has six phase - Uses a Wye and a Delta driving a common array of 6 rectifiers each that are tied anodes to - and cathode (the bar on the rectifier) to either end of a winding - the delta diodes to one end, wye to the other - the center tap is the +. I don't see it as a buck or a boost, simply two series inductors that tie together. (that was a parallel bridge) The series bridge is the same without the inductor
The other odd ball one is the Triple Diametric three phase which has El/Edc - No load rms voltage divided by no load dc voltage. It matches the full wave center tap supply of
2.22 has a 6f ripple frequency and a 180 degree conduction cycle. A double wye - using 6 diodes conducts for only 120 degrees.some interesting notes - Thyristors - relay controls - on the archive site
Don - both good and bad for you. Nice to be at the forefront of power but sometimes when fire is flicking in a storm - we want you there last.
I used to live in a Coastal Redwood forest. I always hated to see the guys come in from the flat land central valley to help out. It was great training, but very dangerous for them. At home, a bucket truck could do everything. Only the power station high lines would need special help, but that was someone else. These young men would have a fallen Fir that was maybe 48" at 4' across a road being held up by the telephone line. The power lines snapped the insulators off the poles. To make things worse, the tree was across a steep narrow road. Cutting the trunk would allow a killing log to roll and the size was much to big to 'tie up'. Finally the short end was tied up in a spider web of lines to every tree they could find. A crane at risk down-hill would hold up a short section as the big tree saw came to play. That was not for those to learn, but someday they might be training someone else. The tree had fallen across most of the width of my property. Tons of limbs.
Martin
Guess it is a case of If you can't dazzle them with brilliance, baffle them with bull shit.
Lew
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