---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 12/14/14: 6 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:51 AM - Re: Re: Alternator Disconnect Z17 vs Z20... (Steve Stearns) 2. 07:57 AM - Re: Re: Alternator Disconnect Z17 vs Z20... (Steve Stearns) 3. 08:19 AM - Re: Re: Alternator Disconnect Z17 vs Z20... (Robert L. Nuckolls, III) 4. 09:12 AM - Re: Alternator Disconnect Z17 vs Z20... (user9253) 5. 01:21 PM - reset time for crowbar (Ken Ryan) 6. 06:15 PM - Re: reset time for crowbar (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 07:51:13 AM PST US Subject: Re: AeroElectric-List: Re: Alternator Disconnect Z17 vs Z20... From: Steve Stearns Bob N. asked: "Are you planning to use one of these two rectifier/regulators or some other product? 170 watts of output probably translate to about 14A maximum available output from the r/r . . . do you plan electric start? Have you conducted a load analysis of all planned accessories to determine that you have enough engine driven power to support the load?" Steve replies: The 264 870 regulator is listed in the engine manual (all I have is hard copy) and on line from rotax suppliers. I don't have a spec sheet on it but given the pictures (big module with a heat sink) it's more than a diode bridge. The engine manual says it doesn't require any load to be in regulation. Our configuration will have electric start and it looks like it needs a good bit of juice per the manual (16AH min battery 10mm2 wire, which looks to me like 2AWG. Engine up front, battery in back so 20' of heavy cable. . The load analysis shows there is plenty of juice (Dynon D60, low-power transponder, radio and engine monitor, LED tip lights and only one halogen on the tail). There are clearly (at least) two version of the 503 (as older one removed has one spark plug per cylinder and the newer one installed has two). If I run across a link for the manuals I have I'll forward them to you. New sanity-check question: The rotax documentation specifies a 16A fuse between the regulator and ship loads (including battery). I'm assuming the location of this fuse is determined by the same factors as an ANL on an alternator equipped ship and, as such, I've put the fuse next to the battery in back, not up front with the regulator. Is there anything about a PM dynamo/regulator combination that would drive putting the fuse up near the regulator? (I still would want something in back near the battery...) Thanks for your help, Steve. ________________________________ Message 2 _____________________________________ Time: 07:57:54 AM PST US Subject: Re: AeroElectric-List: Re: Alternator Disconnect Z17 vs Z20... From: Steve Stearns P.S. Bob N., It looks like you have the same engine manual as I. Check http://www.aeroelectric.com/Mfgr_Data/Rotax/Rotax_503_Electrical.pdf page 18-5. Steve. ________________________________ Message 3 _____________________________________ Time: 08:19:57 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Alternator Disconnect Z17 vs Z20... >Thanks for your help, Good data dump! Need to run a mini-van load of grandkids to ICT but will pray over your posting a bit this evening. Bob . . . ________________________________ Message 4 _____________________________________ Time: 09:12:27 AM PST US Subject: AeroElectric-List: Re: Alternator Disconnect Z17 vs Z20... From: "user9253" Perihelion Design sells lightweight copper-clad cable. http://www.periheliondesign.com/fatwires.htm > Is there anything about a PM dynamo/regulator combination that would drive putting the fuse up near the regulator? Alternators and dynamos are self current limiting. A dynamo rated at 13 amps will not put out much more than that even if the output is shorted. So there is no need to put a fuse near the dynamo or regulator. A fuse is needed near the battery to protect the wires from excessive battery current if a wire is ever shorted to ground. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=435710#435710 ________________________________ Message 5 _____________________________________ Time: 01:21:24 PM PST US From: Ken Ryan Subject: AeroElectric-List: reset time for crowbar How long does it take for the crowbar OVP device to reset, once the over voltage condition has been removed? ________________________________ Message 6 _____________________________________ Time: 06:15:09 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: reset time for crowbar At 15:18 2014-12-14, you wrote: >How long does it take for the crowbar OVP device to reset, once the >over voltage condition has been removed? Power to activate an ov trip comes through the field supply circuit breaker. As soon as the crowbar 'trips' . . . voltage to the field drops to about 1.5v until the breaker opens 10-20 milliseconds later whereupon the field voltage falls to zero. The crowbar module 'latches' ON for as long as any substantial amount of current flows through it. So as soon as the breaker opens, the SCR current goes to zero, the crowbar module is then 'unlatched' or officially 'reset' depending on which term you prefer. Bob . . . ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-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/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-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.