This was just a cobbled up gen set with a diesel power unit like the kind you see pumping water in a farmers field with a generator from a river tug and a driveshaft. There was no feedback from the generator other than the DMM that the throttle man watched and tried to keep it at 240v...
John On 6/5/2012 10:24 AM, gene heskett wrote: > On Tuesday, June 05, 2012 10:58:41 AM John Thornton did opine: > >> Dennis, >> >> It was all we could do to run it for 10 minutes and keep it anywhere >> near 1800 RPM... a real circus that was. >> >> John > The governors on a Cummins 335 we had at KXNE-TV, with a 150kw alternator > on it, was much closer than that. Unloaded about 61HZ, 25% 60.3 50% 59.8, > 75% 60.1, and 100% was when it fell below 59 hZ. It wasn't big enough for > two klystrons at full song so we throttled the visual to about 50%, getting > 58HZ out of it at that load, about 152 kw as I measured it once. Klystrons > are hungry beasts, the overall efficiency to get 30kw visual and 6kw aural, > meant the full song draw was around 250kw. > > So decent governors are out there. This one was purely mechanical but had > some sort of a coil driven by the regulator rigged up that caused the > midrange to be pretty smoothly maintained until full throttle was arrived > at. > > As to being able to retrofit a good governor to a fleabay generator, I've > no clue how co-operative the makers are when the unit is getting long in > the tooth as I've never needed to try. Today, I'd be inclined to make it > out of a UPS running one of those atom boards, running linuxcnc, driving a > stepper attached to the throttle, probably at 5% of the cost of buying the > makers stuff. The encoder watching a phase, the PID module doing the > controls through a stepgen module, sure seems like the avenue to take to > me. If a 60 hz crystal clock can be sourced, one could even phase lock to > that. > >> On 6/4/2012 1:48 PM, ceen...@in-front.com wrote: >>> Did John run it for an hour or longer to be able to repeat the "only >>> one hour run time situation"? I forgot what the capacity of the >>> borrowed generator was to compare it to a 15HP weak leg system. Even >>> if the generator varied in speed and voltage when loaded, one thing >>> should be fairly certain - the phases should be 120 degrees apart. >>> That is helpful by itself. >>> >>> >>> Dennis >>> >>>> He ran it on a Diesel generator, and it did NOT trip. So, it is >>>> SOMTHING about >>>> the power source. >>>> >>>> Jon >>> ---------------------------------------------------------------------- >>> -------- Live Security Virtual Conference >>> Exclusive live event will cover all the ways today's security and >>> threat landscape has changed and how IT managers can respond. >>> Discussions will include endpoint security, mobile security and the >>> latest in malware threats. >>> http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ >>> _______________________________________________ >>> Emc-users mailing list >>> Emc-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/emc-users >> ------------------------------------------------------------------------ >> ------ Live Security Virtual Conference >> Exclusive live event will cover all the ways today's security and >> threat landscape has changed and how IT managers can respond. >> Discussions will include endpoint security, mobile security and the >> latest in malware threats. >> http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users > > Cheers, Gene ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
