Fuel economy measurement across the globe

[Gerhard Fiedler]

Tomás Ó hÉilidhe wrote:

> Gerhard Fiedler wrote:
>> 2008-05-07 is the one that's least ambiguous. It's always yyyy-mm-dd. I
>> think there's an ISO standard for it.
>
> And I bet it's 200 pages long :-D

Bet how much? Think you lost... :)

Given the complexity of the issue, the number of different formats and the
many different ways dates are referred to, this standard is not excessive
at all, IMO.

ISO 8601:2004 Data elements and interchange formats -- Information
interchange -- Representation of dates and times

A good summary:
<http://www.cl.cam.ac.uk/~mgk25/iso-time.html>
Wikipedia, also good:
<http://en.wikipedia.org/wiki/ISO_8601>
More to the point, Wikipedia provides a direct download link for the ISO
document (40 pages):
<http://isotc.iso.org/livelink/livelink/4021199/ISO_8601_2004_E.zip?func=doc.Fetch&nodeid=4021199>

ISO's own summary:
<http://www.iso.org/iso/date_and_time_format>
Here you can buy it (not sure how this relates to the link published in
Wikipedia):
<http://www.iso.org/iso/catalogue_detail?csnumber=40874>

A short overview of the formats in list form, from an older version of ISO
8601 (1988):
<http://www.hydracen.com/dx/iso8601.htm>

The W3C take on this (they basically adopted a subset of ISO 8601):
<http://www.w3.org/QA/Tips/iso-date>
<http://www.w3.org/TR/NOTE-datetime>

Gerhard

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[Olin Lathrop]

Sean Breheny wrote:
> Thanks for the reply, Olin, but I wasn't talking about how the pump
> knows to stop pumping. As I understood it, several piclisters were
> saying that the valve at the nozzle end normally stays closed to
> prevent people from emptying the tube after the pump has shut down. I
> was wondering how the valve at the nozzle end "knows" to close after
> pumping is finished.  I would have thought that it would open whenever
> the handle was squeezed closed.

I'm not sure what you're asking as it's not making much sense.

The valve for starting and stopping gas flow when filling your car is in the
nozzle.  This valve is usually activated by a grip that you squeeze.  When
your tank is full this valve shuts off by itself, or you manually release
the grip to shut it off.  If you were to squeeze the grip again, more gas
would flow, but you'd also get charged for that.

The pump senses when you return the nozzle to the holder in the pump and
completes the billing.  On some pumps this is done by swinging a lever which
phisically locks the nozzle in place.  It won't be released until the next
billing has started.  Some pumps shut down the internal pump, but of course
it is turned on again when the nozzle is removed by the next customer.

I'm not really sure what you're asking.  Haven't you ever filled up a car
before?  If not, go with someone next time they do it.  It's really not
complicated, and it's pretty obvious how the system works when you look at
it.


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[M. Adam Davis-2]

On 7/11/08, Olin Lathrop <olin_piclist@...> wrote:
> Some pumps shut down the internal pump, but of course
> it is turned on again when the nozzle is removed by the next customer.

The modern gas stations where I've seen the 'back room' have a
variable frequency drive pump for each storage tank of fuel.  The
pumps feed all the dispensers.  This method is less expensive overall
and easier to stop in case of emergency.  Generally they don't buy a
large enough pump to feed all the dispensers at once, so when lots of
people are fueling you can tell it's fuelling more slowly than usual.
further, some stations buy smaller pumps for the less frequently used
fuels.

The dispensors aren't much more than payment machines with meters (and
ads) and safety equipment...

-Adam

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[Sean Breheny]

Hi Olin,

I may be relatively young (28) but I've been driving for 10 years and
certainly have filled up a car before :)

Let me try to rephrase my question by giving an example.

Let's say I go to fill up. First, I slide my credit card and select
the type of gas I want. Then I remove the nozzle and place it into the
filler tube in the car. Next I squeeze the handle and the pump starts
pumping fuel.

When the tank fills and the nozzle detects gas next to the small holes
on the outside of the nozzle, it closes the valve at the nozzle and
the gas stops flowing. I could "top it off" by continuing to cycle the
handle through open and closed.

Now, I put the nozzle back into the holder on the pump and complete
the transaction. At this point, the entire tube from the pump to the
nozzle is still full of gas, right?

Now if I remove the nozzle from the holder again, without swiping my
card again, and then squeeze the handle, how come I don't get the
contents of the tube spilling out? Sure, the pump will not deliver
more gas into the tube, but I would think that the gas inside the tube
could still come out.

I can only think of a few ways this could be prevented:

1) suck the fuel back out of the tube into the pump
2) somehow enable the pump to signal the valve at the nozzle to remain
closed when there isn't an active transaction going on.
3) Have the entire connection from pump through to nozzle be so air
tight that no air could get back in to displace the gasoline so that
it will not come out unless the pump is pumping (I'm having trouble
trying to determine whether this would work as it seems that normally
even a tube which is sealed at one end and filled with liquid can
still be emptied from the other end).
4) have the valve at the nozzle end require a minimum pressure to open
(which is greater than the pressure developed by gravity on the
vertical height of gasoline in the tube)

My question is which of these is done (or what possibility did I not consider)

Thanks,

Sean


On Fri, Jul 11, 2008 at 8:48 AM, Olin Lathrop <olin_piclist@...> wrote:

>
> I'm not sure what you're asking as it's not making much sense.
>
> The valve for starting and stopping gas flow when filling your car is in the
> nozzle.  This valve is usually activated by a grip that you squeeze.  When
> your tank is full this valve shuts off by itself, or you manually release
> the grip to shut it off.  If you were to squeeze the grip again, more gas
> would flow, but you'd also get charged for that.
>
> The pump senses when you return the nozzle to the holder in the pump and
> completes the billing.  On some pumps this is done by swinging a lever which
> phisically locks the nozzle in place.  It won't be released until the next
> billing has started.  Some pumps shut down the internal pump, but of course
> it is turned on again when the nozzle is removed by the next customer.
>
> I'm not really sure what you're asking.  Haven't you ever filled up a car
> before?  If not, go with someone next time they do it.  It's really not
> complicated, and it's pretty obvious how the system works when you look at
> it.
>
>
> ********************************************************************
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> [phone].  Gold level PIC consultants since 2000.
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[Carl Denk]

In the USA, the EPA mandates certain spill prevention and leak detection
methods. One of these is, if the nozzle valve is open when the pump
starts ( or manifold valve in the case of many dispensers on one pump).
The unrestricted hose end will be interpreted as a broken hose leaking
and the mechanical (no electrical required) leak detector before the
dispenser hose will shut the flow off to a trickle. Reseting requires
fixing the leak (close the nozzle valve) and shutting off the source
(pump usually) briefly.

Here is a good description of the entire fuel dispensing system, above
described is "MLD"
http://www.acetank.com/Public/Solutions/ServiceStations/index.cfm?requesttimeout=100

Sean Breheny wrote:

> Hi Olin,
>
> I may be relatively young (28) but I've been driving for 10 years and
> certainly have filled up a car before :)
>
> Let me try to rephrase my question by giving an example.
>
> Let's say I go to fill up. First, I slide my credit card and select
> the type of gas I want. Then I remove the nozzle and place it into the
> filler tube in the car. Next I squeeze the handle and the pump starts
> pumping fuel.
>
> When the tank fills and the nozzle detects gas next to the small holes
> on the outside of the nozzle, it closes the valve at the nozzle and
> the gas stops flowing. I could "top it off" by continuing to cycle the
> handle through open and closed.
>
> Now, I put the nozzle back into the holder on the pump and complete
> the transaction. At this point, the entire tube from the pump to the
> nozzle is still full of gas, right?
>
> Now if I remove the nozzle from the holder again, without swiping my
> card again, and then squeeze the handle, how come I don't get the
> contents of the tube spilling out? Sure, the pump will not deliver
> more gas into the tube, but I would think that the gas inside the tube
> could still come out.
>
> I can only think of a few ways this could be prevented:
>
> 1) suck the fuel back out of the tube into the pump
> 2) somehow enable the pump to signal the valve at the nozzle to remain
> closed when there isn't an active transaction going on.
> 3) Have the entire connection from pump through to nozzle be so air
> tight that no air could get back in to displace the gasoline so that
> it will not come out unless the pump is pumping (I'm having trouble
> trying to determine whether this would work as it seems that normally
> even a tube which is sealed at one end and filled with liquid can
> still be emptied from the other end).
> 4) have the valve at the nozzle end require a minimum pressure to open
> (which is greater than the pressure developed by gravity on the
> vertical height of gasoline in the tube)
>
> My question is which of these is done (or what possibility did I not consider)
>
> Thanks,
>
> Sean
>
>
> On Fri, Jul 11, 2008 at 8:48 AM, Olin Lathrop <olin_piclist@...> wrote:
>  
>> I'm not sure what you're asking as it's not making much sense.
>>
>> The valve for starting and stopping gas flow when filling your car is in the
>> nozzle.  This valve is usually activated by a grip that you squeeze.  When
>> your tank is full this valve shuts off by itself, or you manually release
>> the grip to shut it off.  If you were to squeeze the grip again, more gas
>> would flow, but you'd also get charged for that.
>>
>> The pump senses when you return the nozzle to the holder in the pump and
>> completes the billing.  On some pumps this is done by swinging a lever which
>> phisically locks the nozzle in place.  It won't be released until the next
>> billing has started.  Some pumps shut down the internal pump, but of course
>> it is turned on again when the nozzle is removed by the next customer.
>>
>> I'm not really sure what you're asking.  Haven't you ever filled up a car
>> before?  If not, go with someone next time they do it.  It's really not
>> complicated, and it's pretty obvious how the system works when you look at
>> it.
>>
>>
>> ********************************************************************
>> Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
>> [phone].  Gold level PIC consultants since 2000.
>> --
>> http://www.piclist.com PIC/SX FAQ & list archive
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
>>
>>    

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[Olin Lathrop]

Sean Breheny wrote:

> Let's say I go to fill up. First, I slide my credit card and select
> the type of gas I want. Then I remove the nozzle and place it into the
> filler tube in the car. Next I squeeze the handle and the pump starts
> pumping fuel.
>
> When the tank fills and the nozzle detects gas next to the small holes
> on the outside of the nozzle, it closes the valve at the nozzle and
> the gas stops flowing. I could "top it off" by continuing to cycle the
> handle through open and closed.
>
> Now, I put the nozzle back into the holder on the pump and complete
> the transaction. At this point, the entire tube from the pump to the
> nozzle is still full of gas, right?
>
> Now if I remove the nozzle from the holder again, without swiping my
> card again, and then squeeze the handle, how come I don't get the
> contents of the tube spilling out? Sure, the pump will not deliver
> more gas into the tube, but I would think that the gas inside the tube
> could still come out.

It may be that even with a wide open valve that air can't get back up into
the hose to displace the gas.  There must be some elasticity in the hose and
you probably would get a little extra gas.

In any case, it would be fraud to try to take more gas from the pump after
you indicated you were done by placing the nozzle back into the holder.  If
you could get a meaningful amount of gas this way and there were enough
dirtbags that did this, there would be measures to prevent it.

This is all rather different from what Tomas was talking about.  Can someone
from Ireland comment of whether the system really is different over there,
or did Tomas just get confused in the excitement of thinking he was getting
something for nothing?


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[Walter Banks]

> Sean Breheny wrote:
> > Let's say I go to fill up. First, I slide my credit card and select
> > the type of gas I want. Then I remove the nozzle and place it into the
> > filler tube in the car. Next I squeeze the handle and the pump starts
> > pumping fuel.
> >
> > When the tank fills and the nozzle detects gas next to the small holes
> > on the outside of the nozzle, it closes the valve at the nozzle and
> > the gas stops flowing. I could "top it off" by continuing to cycle the
> > handle through open and closed.
> >
> > Now, I put the nozzle back into the holder on the pump and complete
> > the transaction. At this point, the entire tube from the pump to the
> > nozzle is still full of gas, right?
> >
> > Now if I remove the nozzle from the holder again, without swiping my
> > card again, and then squeeze the handle, how come I don't get the
> > contents of the tube spilling out? Sure, the pump will not deliver
> > more gas into the tube, but I would think that the gas inside the tube
> > could still come out.

In my mis-spent youth at 2am I remember being about 40 miles from
home and out of gas in a small town whose gas stations had long since
closed

We drained the hoses from a couple gas stations and got enough to get
home. This was back in the days when hoses were never locked to the
pumps.

w..

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[M. Adam Davis-2]

Consulting the Oracle (google) we find this example:

http://www.opw-fc.com/product_category.aspx?cid=7

apparently some fuel nozzles (pump handles to us, fuel nozzle to the
industry) do allow one to dispense product from an unpressurized hose.

There are fuel nozzles, however, that will not dispense product until
the line is under pressure, preventing this sort of theft.  These
pressure sensitive nozzles are marketed more as spill and 'loss'
prevention.

-Adam

On 7/11/08, Sean Breheny <shb7@...> wrote:

> Hi Olin,
>
> I may be relatively young (28) but I've been driving for 10 years and
> certainly have filled up a car before :)
>
> Let me try to rephrase my question by giving an example.
>
> Let's say I go to fill up. First, I slide my credit card and select
> the type of gas I want. Then I remove the nozzle and place it into the
> filler tube in the car. Next I squeeze the handle and the pump starts
> pumping fuel.
>
> When the tank fills and the nozzle detects gas next to the small holes
> on the outside of the nozzle, it closes the valve at the nozzle and
> the gas stops flowing. I could "top it off" by continuing to cycle the
> handle through open and closed.
>
> Now, I put the nozzle back into the holder on the pump and complete
> the transaction. At this point, the entire tube from the pump to the
> nozzle is still full of gas, right?
>
> Now if I remove the nozzle from the holder again, without swiping my
> card again, and then squeeze the handle, how come I don't get the
> contents of the tube spilling out? Sure, the pump will not deliver
> more gas into the tube, but I would think that the gas inside the tube
> could still come out.
>
> I can only think of a few ways this could be prevented:
>
> 1) suck the fuel back out of the tube into the pump
> 2) somehow enable the pump to signal the valve at the nozzle to remain
> closed when there isn't an active transaction going on.
> 3) Have the entire connection from pump through to nozzle be so air
> tight that no air could get back in to displace the gasoline so that
> it will not come out unless the pump is pumping (I'm having trouble
> trying to determine whether this would work as it seems that normally
> even a tube which is sealed at one end and filled with liquid can
> still be emptied from the other end).
> 4) have the valve at the nozzle end require a minimum pressure to open
> (which is greater than the pressure developed by gravity on the
> vertical height of gasoline in the tube)
>
> My question is which of these is done (or what possibility did I not consider)
>
> Thanks,
>
> Sean
>
>
> On Fri, Jul 11, 2008 at 8:48 AM, Olin Lathrop <olin_piclist@...> wrote:
> >
> > I'm not sure what you're asking as it's not making much sense.
> >
> > The valve for starting and stopping gas flow when filling your car is in the
> > nozzle.  This valve is usually activated by a grip that you squeeze.  When
> > your tank is full this valve shuts off by itself, or you manually release
> > the grip to shut it off.  If you were to squeeze the grip again, more gas
> > would flow, but you'd also get charged for that.
> >
> > The pump senses when you return the nozzle to the holder in the pump and
> > completes the billing.  On some pumps this is done by swinging a lever which
> > phisically locks the nozzle in place.  It won't be released until the next
> > billing has started.  Some pumps shut down the internal pump, but of course
> > it is turned on again when the nozzle is removed by the next customer.
> >
> > I'm not really sure what you're asking.  Haven't you ever filled up a car
> > before?  If not, go with someone next time they do it.  It's really not
> > complicated, and it's pretty obvious how the system works when you look at
> > it.
> >
> >
> > ********************************************************************
> > Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
> > [phone].  Gold level PIC consultants since 2000.
> > --
> > http://www.piclist.com PIC/SX FAQ & list archive
> > View/change your membership options at
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> >
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[CDB-3]

:: As I understood it, several piclisters were
:::: saying that the valve at the nozzle end normally stays closed to
:::: prevent people from emptying the tube after the pump has shut
:::: down. I
:::: was wondering how the valve at the nozzle end "knows" to close
:::: after
:::: pumping is finished.  I would have thought that it would open
:::: whenever
:::: the handle was squeezed closed.

Is there a syphoning effect happening at the pump when it is switched
off?  One of the reasons why some pumps seem to have a lag between
squeezing the trigger, fuel being dispensed (and annoyingly the meter
whizzes around before fuel has started to flow) is due to the fuel
station not priming it's pumps properly and leaking pump seals. So it
maybe that the hose is empty if the fuel is 'sucked' back into the
pump, though the primed pump should expel the air quickly when the
next user switches the pump back on.

( a fuel stations manager's trick to skim some extra money is not to
prime the pumps each day, the fuel dispensed that is registered, but
actually hasn't flowed, may be smallish, but over the course of a
day's trade, amounts to 100% profit.)

Colin
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[Carl Denk]

The pumps are all submersible, and have a check valve after the pump
turbines (very close, the entire pump including motor, turbine and check
valve, probably less than 2 feet long). The entire system is liquid(and
for all practical purposes air too) tight, When the pump is turned on
for the first time (new, after maintenance or running the tank dry)
after being immersed in fuel, it will  self prime very quickly and the
air will get compressed in the piping, dispenser, and hose to the
nozzle. Opening the nozzle valve will allow the air to be expelled from
the system. Once this is done (should be done by the system operator,
and not customer) there should not be any air in the system, though it
would be possible to drain the liquid in the hose by turning off the
pump (read as including a manifold valve if multi dispenser system) and
opening the nozzle valve with the nozzle lower than it's attachment to
the dispenser. Most meters I have seen only measure liquid, and not air,
but this may not be always true. Older dispensers (1950's) had a glass
sight glass with a little turbine in it to verify there was flow, and no
air.

The nozzle valve is a spring loaded normally closed valve, otherwise,
when the pump is turned on there would be flow, which would not be safe
big time. The nozzle valve closes for 2 reasons: 1: Stop squeezing the
lever. 2: A full vehicle tank condition is sensed, and the valve is
closed automatically, no matter what is keeping the valve open, either a
hand, the auto fill latch, or a gas cap or something jambed under the
hand lever.

Stretching the hose might yield a fluid ounce or so, I don't consider it
worth my time. Draining the hose, is cheating the next customer since he
is going to get charged for it.

One item hasn't been discussed, vapor recovery. As a tank gets filled,
fuel vapors are displaced by fresh liquid. Conversely, as a tank is
emptied, fresh air is drawn in, unless there is another hose to allow
the vapors to transfer from the filled tank to the emptied tank. For
vehicle filling, there is a neoprene (usually black) accordion boot on
the tube that goes in the vehicle fill point sealing the area, and the
vapors leave the nozzle in a coaxial hose (it will be large diameter
than usual). For tank truck delivery, there is a separate hose the truck
drive must connect to return the vapors to the transport tank. Upon
return to the distribution terminal where we will assume the fuel is
delivered via a pipe line from some distant point, the fuel vapors are
condensed back to product. I have been told this could result in 5
gallons recovered from a 8000 gallon transport.

cdb wrote:

> :: As I understood it, several piclisters were
> :::: saying that the valve at the nozzle end normally stays closed to
> :::: prevent people from emptying the tube after the pump has shut
> :::: down. I
> :::: was wondering how the valve at the nozzle end "knows" to close
> :::: after
> :::: pumping is finished.  I would have thought that it would open
> :::: whenever
> :::: the handle was squeezed closed.
>
> Is there a syphoning effect happening at the pump when it is switched
> off?  One of the reasons why some pumps seem to have a lag between
> squeezing the trigger, fuel being dispensed (and annoyingly the meter
> whizzes around before fuel has started to flow) is due to the fuel
> station not priming it's pumps properly and leaking pump seals. So it
> maybe that the hose is empty if the fuel is 'sucked' back into the
> pump, though the primed pump should expel the air quickly when the
> next user switches the pump back on.
>
> ( a fuel stations manager's trick to skim some extra money is not to
> prime the pumps each day, the fuel dispensed that is registered, but
> actually hasn't flowed, may be smallish, but over the course of a
> day's trade, amounts to 100% profit.)
>
> Colin
> --
> cdb, colin@... on 12/07/2008
>  
> Web presence: www.btech-online.co.uk  
>  
> Hosted by:  www.1and1.co.uk/?k_id=7988359
>  
>
>
>
>  
>  
>  
>
>  

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[Olin Lathrop]

Carl Denk wrote:

> The pumps are all submersible, and have a check valve after the pump
> turbines (very close, the entire pump including motor, turbine and check
> valve, probably less than 2 feet long). The entire system is liquid(and
> for all practical purposes air too) tight, When the pump is turned on
> for the first time (new, after maintenance or running the tank dry)
> after being immersed in fuel, it will  self prime very quickly and the
> air will get compressed in the piping, dispenser, and hose to the
> nozzle. Opening the nozzle valve will allow the air to be expelled from
> the system. Once this is done (should be done by the system operator,
> and not customer) there should not be any air in the system, though it
> would be possible to drain the liquid in the hose by turning off the
> pump (read as including a manifold valve if multi dispenser system) and
> opening the nozzle valve with the nozzle lower than it's attachment to
> the dispenser. Most meters I have seen only measure liquid, and not air,
> but this may not be always true.

This is generally how all pumps work I've seen in recent decades, but things
were not always so.  Back when I was in grade school we were driving thru
northern Arizona and New Mexico, and happened to need gas in the Hopi indian
reservation.  We had ask around a bit for where there was a gas station, but
eventually we were directed to a town on the top of a hill a few miles from
the main road.  The gas pump had a big upside down jar on top, looking
sortof like one of those replacable water jugs of office water coolers.
Except this jar was a bit bigger, glass, and on top of the pump at eye
level.  The gas station attendent asked how much gas we wanted, then worked
a mechanical pump by hand that caused the big glass jar to fill up.  It was
marked off in gallons.  Once he got to the gallons we requested, he stopped
pumping and the car was filled by gravity from the big jar.  Pretty cool.  I
vaguely remember gas cost in the low 30 cents per gallon range.

The cheapest gas I remember was in the middle of noplace Nevada (maybe Utah
or Arizona).  It was at a crossroads of two paved roads with a gas station
on 3 of the 4 corners with pretty much nothing else around for 10s of miles.
The gas price was 18 cents/gallon, which was a great deal even then.


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[phone].  Gold level PIC consultants since 2000.
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[Carl Denk]

Yep, that was the equipment used in the 30's and 40's. By the 50's they
were all gone except for a few isolated instances. Today, they are
museum pieces. The neat thing of those devices, was, you could see the
fuel color and the quantity you were getting. Today we rely on the
electronics and we all know how good and how that can be hacked. In
Ohio, most states are similar, the county auditor has people that go
around with calibrated containers, and check the accuracy of the meters.
The dispenser if good, gets a dated seal sticker that is good for a
year. Some states check the quality of the fuel for purity and octane
rating, Ohio does not!

Last week, I picked up 40 gallons of off road (no highway tax) diesel
fuel for our tractor at the local distributor that services farmers and
businesses. I pumped from a 3000 gallon above the ground tank with a
pump/meter unit mounted on top. This was the exception to the
submersible tank setup. The nozzle tube was at least 1" diameter, no way
could you get it into a car fill point. :)

Olin Lathrop wrote:

> Carl Denk wrote:
>  
>> The pumps are all submersible, and have a check valve after the pump
>> turbines (very close, the entire pump including motor, turbine and check
>> valve, probably less than 2 feet long). The entire system is liquid(and
>> for all practical purposes air too) tight, When the pump is turned on
>> for the first time (new, after maintenance or running the tank dry)
>> after being immersed in fuel, it will  self prime very quickly and the
>> air will get compressed in the piping, dispenser, and hose to the
>> nozzle. Opening the nozzle valve will allow the air to be expelled from
>> the system. Once this is done (should be done by the system operator,
>> and not customer) there should not be any air in the system, though it
>> would be possible to drain the liquid in the hose by turning off the
>> pump (read as including a manifold valve if multi dispenser system) and
>> opening the nozzle valve with the nozzle lower than it's attachment to
>> the dispenser. Most meters I have seen only measure liquid, and not air,
>> but this may not be always true.
>>    
>
> This is generally how all pumps work I've seen in recent decades, but things
> were not always so.  Back when I was in grade school we were driving thru
> northern Arizona and New Mexico, and happened to need gas in the Hopi indian
> reservation.  We had ask around a bit for where there was a gas station, but
> eventually we were directed to a town on the top of a hill a few miles from
> the main road.  The gas pump had a big upside down jar on top, looking
> sortof like one of those replacable water jugs of office water coolers.
> Except this jar was a bit bigger, glass, and on top of the pump at eye
> level.  The gas station attendent asked how much gas we wanted, then worked
> a mechanical pump by hand that caused the big glass jar to fill up.  It was
> marked off in gallons.  Once he got to the gallons we requested, he stopped
> pumping and the car was filled by gravity from the big jar.  Pretty cool.  I
> vaguely remember gas cost in the low 30 cents per gallon range.
>
> The cheapest gas I remember was in the middle of noplace Nevada (maybe Utah
> or Arizona).  It was at a crossroads of two paved roads with a gas station
> on 3 of the 4 corners with pretty much nothing else around for 10s of miles.
> The gas price was 18 cents/gallon, which was a great deal even then.
>
>
> ********************************************************************
> Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
> [phone].  Gold level PIC consultants since 2000.
>  

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[Nate Duehr]

On Jul 10, 2008, at 6:12 PM, Tomás Ó hÉilidhe wrote:

>
>
> Gerhard Fiedler wrote:
>> 2008-05-07 is the one that's least ambiguous. It's always yyyy-mm-
>> dd. I
>> think there's an ISO standard for it.
>
>
> And I bet it's 200 pages long :-D



And if you're really unlucky, instead of using ISO standards, you have  
to live in the telecom world where the ITU is the place to go.  ITU  
standards will often have an Annex -- an add-on that changes the  
standard completely.

And if it's from ITU it costs big money to get a "real" copy.  And  
upon receiving it and reading it you find that it describes six  
different ways to do the same thing, therefore doesn't "define" a  
standard at all.

Start with ITU H.320, compare to H.323 -- one's ISDN, the other IP --  
but after that they're the same.  Then try to find all of the  
appropriate videoconferencing standards underneath H.323.  Then  
realize that you're looking for an audio answer and the overlying  
standard just calls out other standards, in this case... it's actually  
G.729.1 Annex C that you're REALLY trying to find.

And shake your head when you realize that G.729.1 and G.729.1 Annex C  
aren't even using the same technology or CODEC, but ended up the same  
number because G.729 was "extensible".

Did the above just this week... because some $20 software client said  
it did G.729.1 and the customer thought that meant it would do G.729.1  
Annex C.

And we pay for the privilege of having copies of this slop. :-)

--
Nate Duehr
nate@...




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[Nate Duehr]

On Jul 11, 2008, at 6:55 PM, Carl Denk wrote:

> Last week, I picked up 40 gallons of off road (no highway tax) diesel
> fuel for our tractor at the local distributor that services farmers  
> and
> businesses. I pumped from a 3000 gallon above the ground tank with a
> pump/meter unit mounted on top. This was the exception to the
> submersible tank setup. The nozzle tube was at least 1" diameter, no  
> way
> could you get it into a car fill point. :)


If it was the "standard" larger diesel nozzle size used by 18-
wheelers, the Volkswagen diesel cars not only can handle the larger  
diameter nozzle, but also have a special air return system (a valve  
activated by the larger nozzle being inserted opens an air "escape"  
valve that allows air to escape at a much faster rate from the fuel  
tank up through a tube to that plastic valve in the filler port.

This allows you to fill up at the much bigger nozzle pumps the trucks  
use at a horrendously fast rate.  But you'd better watch it closely  
because it'll easily overfill and cause a spill at those pumps.

You have to love VW engineers for including it, though.

Since this air return system also incorporates a small pocket of air  
molded into the top of the fuel tank, many VW diesel drivers will  
carry a few disposable latex gloves or similar and on long trips where  
they want the maximum fuel in the tank during a fill-up, they'll reach  
in with a finger and push the air valve open while using a regular  
"car sized" small diesel nozzle, which will allow for "topping off"  
the tank with quite a bit more fuel into that "air space" at the top.

It's a pretty significant amount of fuel, but I don't remember how  
much.  I didn't have gloves with me the day I messed with it on my  
wife's Jetta Wagon, and I smelled like diesel for the rest of the day,  
even with trying to wash it off... gloves highly recommended.  :-)

Meanwhile the thing's highway fuel economy is so high, that even if I  
watch my water and/or coffee intake when on a long road trip, the  
diesel car will always outlast my bladder -- "extra fillup" or a  
regular one.   One tank of fuel from just south of Mt. Rushmore, South  
Dakota to the south suburbs of Denver, CO is WAY too long to be in the  
driver's seat... I didn't even attempt it.  But I didn't have to fill  
up...

Not particularly interested in finding out what Deep Vein Thrombosis  
and pulmonary edema from a blood clot passing through my heart is like.

Only really messed with filling the car with the larger "truck" pumps  
once.  It was full so fast, it was amazing, even only opening the pump  
to the first "notch" on the locking mechanism.  WHOOOOSH.  Nice if you  
had to, but not really worth the nervousness that goes with it.

--
Nate Duehr
nate@...



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