On Thursday, May 31, 2012 07:34:36 AM John Thornton did opine: > Interestingly I had a bit of time last night and did some more voltage > measurements with various bits turned on to load the RPC. > > RPC only running AB=245 BC=253 AC=253 > With the BP 308 (Simodrive 611) powered up AB=245 BC=245 AC=245 > With the Samson 7.5hp manual lathe spindle at 660 RPM AB=244 BC=232 > Adding the 308's spindle at 1000 RPM AB=244 BC=234 AC=229 > Ramping up to 3000 RPM on the 308's spindle AB=244 BC=234 AC=227
The phase angles are shifting some. And the sag might mean you would have to go back to the 15 horse idler for the RPC. You said it was noisy, would fresh bearings help? OTOH, if its an open frame Ajax, they howl like fire sirens anyway. A 15 horse water pump we had as a backup at KXNE-TV, easily added 30 db to the noise level as it wasted at least a horse on internal cooling fans. I didn't think much of it, but it did get 1000 or more running hours without problems while we ordered up and installed seal kits in the other, much quieter pump. Klystron amplifiers need about 70 GPM of cooling water each when at full beam current, so between the 2 we were moving about 120 GPM. You don't scrimp on cooling those at $150,000 per cooling failure. A 3 phase Heineman breaker single phased the pump, I recognized the sound and my hand was about 1/2 way to the kill button when the building entrance breaker, 1200 amps/phase, went down like a 8 gage shotgun & left me standing in the dark to contemplate my sins. One klystron full of water where it should have had a very good vacuum. The beam ate a hole in the anode bucket in less than a second. That of course crow barred the 20 kv beam supply, and things all went to hell from there. They had to call in a quorum of the unicameral legislature to buy me a replacement. How hot is the 10HP running after an hour with both loads on it? > So it appears I need to do a bit more tuning with the caps as the load > is dragging down the voltage on the generated leg. Interestingly with > the Samson running the BP 308 would start from 0 to a higher RPM than > with it off even though the voltage had been pulled down by the Samson's > spindle. Things that make you go "humm". > I also tried adjusting some of the pots on the 611 spindle drive with no > conclusive results from that experiment. > > I did hear back from the transformer guy Gene gave me the link to. Seems > to be a fair price so I'll investigate that more as well as look at the > diesel generator next week and do some more tuning on the RPC. > > "Hi John, > The cost for a 240 VAC 30A 3-phase isolation transformer is $1250. > Factory lead time is approximately 4-5 weeks. > If you need any additional information or would like to order the unit, > please feel to contact me by phone or email. > Regards, > Jeff > Jeff Weinberg > Harbach Electronics, LLC" > > John When you asked for the quote, did you include some extra primary taps so that a 5 to 10% step up/down could be done? That could turn out to be handier than sliced bread or bottled beer. There will be a cost associated with the taps of course. Whomever I talked to before, seemed to be a decent sort. And the stuff is top quality in my experience. [...] Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> Alex Haley was adopted! ------------------------------------------------------------------------------ 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
