On 7/11/08, Olin Lathrop 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 -- EARTH DAY 2008 Tuesday April 22 Save Money * Save Oil * Save Lives * Save the Planet http://www.driveslowly.org -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist