---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Wed 06/06/12: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 09:17 AM - Re: Re: Yak 55M Voltage regulator Overvoltage? (Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E) 2. 09:44 AM - Re: Re: Yak 55M Voltage regulator Overvoltage? (Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E) 3. 04:24 PM - EIS 4000 for sale (Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E) ________________________________ Message 1 _____________________________________ Time: 09:17:31 AM PST US Subject: RE: Yak-List: Re: Yak 55M Voltage regulator Overvoltage? From: "Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E" Rob, While I didn't say it out-loud, I already know what happens when you do what I was talking about earlier. I am pulling the actual terminal marking from memory, but on the DMR-200 I think it is the terminal marked with "A" that connects directly to the MAIN CONTACTOR coil itself. If you put 28 VDC on that terminal, the MAIN CONTACTOR relay will close and complete the circuit between generator output and main aircraft 28 VDC bus. While I do not recommend this to anyone else, I have connected that terminal to a switch inside of my aircraft, so that I can close the MAIN CONTACTOR relay manually if I desire to. It is wired to the old oil dilution switch, which is of course spring loaded "OFF". You can probably figure out why I have done this. So toss theory out the window at this point. If you close the main contactor relay on the DMR-200 with the engine not running, the main battery fuse will blow. Or I should say: "At least mine did". [wink to you too!] :-) Mark -----Original Message----- From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of Rob Rowe Sent: Tuesday, June 05, 2012 10:35 PM Subject: Yak-List: Re: Yak 55M Voltage regulator Overvoltage? > > mark.bitterlich(at)navy.m Posted: Tue Jun 05, 2012 5:03 pm > ... > If the main contactor was indeed fused closed, when the engine stopped, > it should blow the main battery fuse, because at that point the "motor" > would not be spinning and would represent a dead short to ground, or > darn close to it. > ... > Fair point Mark, but with the differential shunt relay in series (as Brian mentioned) plus battery internal resistance, generator windings etc only needs to be collectively c.1ohm and the current gets limited to 20+Amps, maybe not enough to take the main fuse out. With the differential shunt (reverse current) relay needing 10-25 Amps (from spec) to operate anyway then a corroded / loose connection could readily add a few ohms and prevent the contactor release from even being triggered. Have just noted the -55M doesn't have an ammeter as standard fit, so scratch that check option. Anyway let's see what Mark S come back with, if nothing else it will at least help eliminate this from the potential fault list [Wink] Cheers, Rob R Read this topic online here: http://forums.matronics.com/viewtopic.php?p=374812#374812 ________________________________ Message 2 _____________________________________ Time: 09:44:38 AM PST US Subject: RE: Yak-List: Re: Yak 55M Voltage regulator Overvoltage? From: "Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E" On the Russian designs, the DMR-200 Combined Device contains the reverse current cut-out circuit. There are a number of relays contained in that device, one of which is used for reverse current sensing. The reverse current relay is in series with the Main Contactor relay. When the reverse current sensing relay is activated, it in turn removes coil voltage from the main contactor relay thus opening the circuit from generator output to the main aircraft bus. If the DMR-200 main contactor relay is closed with the generator at rest, the battery fuse will blow in a YAK-50. I know that because ... I've done it. Mark -----Original Message----- From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of Brian Lloyd Sent: Tuesday, June 05, 2012 1:59 PM Subject: Re: Yak-List: Re: Yak 55M Voltage regulator Overvoltage? On Tue, Jun 5, 2012 at 10:00 AM, Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E wrote: Cherry Point, MALS-14 64E" Rob, I think his voltage measurements were at the generator and not the main bus. Don't know that for sure, but I think so. This would make 15 volts at idle pretty normal. (The DMR-200 would open and you would be reading straight generator voltage) If the main contactor was indeed fused closed, when the engine stopped, it should blow the main battery fuse, because at that point the "motor" would not be spinning and would represent a dead short to ground, or darn close to it. Agreed? That is certainly what I would expect if the cutout relay (what I think you are calling the main contactor) were to weld closed. It is intended to open when current starts to flow from bus to generator armature rather than the other way around. OTOH, the overcurrent relay would probably prevent serious damage. -- Brian Lloyd, WB6RQN/J79BPL 3191 Western Dr. Cameron Park, CA 95682 brian@lloyd.com +1.767.617.1365 (Dominica) +1.916.877.5067 (USA) ________________________________ Message 3 _____________________________________ Time: 04:24:47 PM PST US Subject: Yak-List: EIS 4000 for sale From: "Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E" I am sending this advertisement for my friend Hubie Tolson. For anyone that is interested, I know this gentleman personally and vouch for him totally. Mark Bitterlich -------------------------------------------------------------------- New. Never Used or Installed. Set up for M14 Russian 9 Cylinder Radial ($50 Factory Charge to convert to Lycoming) Model EIS 4000 SN 10903 28 Volt Software Updated recently by Grand Rapids Technology. Software Version: 44V81F Includes Sensors, Connectors, Etc Includes Fuel Flow Option/Hardware. EIS 4000 Brochure: http://www.grtavionics.com/File/EIS/M469.pdf Retail Over $1600 Buy For $1200 Contact me off list. Hubie Tolson 227 East Front Street New Bern, NC 28560 USA Cell: 252-670-9370 Fax: 252-638-7456 Web: www.hubietolson.com, www.uhfdevelopmentgroup.com Email: hubie@hubietolson.com ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message yak-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Yak-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/yak-list Browse Digests http://www.matronics.com/digest/yak-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.