---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 01/23/22: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:17 PM - Re: Starter fuse blew x3 (Robert L. Nuckolls, III) 2. 08:06 PM - Re: Starter fuse blew x3 (David Saylor) ________________________________ Message 1 _____________________________________ Time: 12:17:08 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Starter fuse blew x3 At 12:56 PM 1/22/2022, you wrote: >Thanks Ken.=C2 Do you mean the contacts in the >solenoid attached to the starter?=C2 I've >replaced the starter in the past but never >serviced the contacts.=C2 I can do that. > >The fuse that's blowing isn't in that circuit >though.=C2 I should clarify my terms.=C2 The fuse >that's blowing powers the starter contactor.=C2 I >called it the starter solenoid.=C2 The starter >contactor coil has dedicated external terminals >for the coil and isn't associated with the high >current starter or solenoid wiring.=C2 Cleaning >up the solenoid contacts is doable but I think >my terminology muddied the waters.=C2 Or do you >think starting current is getting pulled through the starter relay coil? > The SlickStart device is basically a capacitor discharge ignition system with a special feature, instead of delivering one really hot spark per timing event, it delivers a series of sparks for each timing event. You can get a peek inside this critter by reviewing a patent found here: https://www.freepatentsonline.com/5630384.pdf This is an alternative to the electro-mechanical 'vibrator' known as "shower-of-sparks" that's been around for about a century. SOS system use ship's battery energy conducted through an electro-mechanical interrupter (vibrator or buzzer) to deliver a series of energy pulses into the PRIMARY winding of a magneto during 'points open' interval immediately following a spark timing event. This method of spark generation is not unlike the Kettering points/condenser/ coil system used on gazillions of cars. The magneto's primary/secondary windings are used as a combination energy storage and 'step up' transformer to convert low voltage, high current pulses in the primary into a stream of sparks at the secondary which are conducted out to the plug(s) by a distributor. SlickStart does a similar thing but only uses the step-up feature of the magneto's magnetics to convert a stream of capacitor discharges into the desired high voltage events at the secondary. The SS electronics don't really take much power as we might guess from the recommended size of the fuse. I've not yet found the stated current draw in SlickStart literature but the patent speaks to something on the order of 3A consistent with the 5A fuse callout. Intermittent duty contactors can draw upwards of 3-4 amps themselves. So the combination max current would push a 5A fuse. I'd design for 10A in this circuit. If one of the two loads is causing nuisance trips of the fuse, I would suggest the following: Put a 15A fuse in at the fuse-bus-block. Put a temporary 7A fuse in series with the starter contactor and SlickStart power leads at the starter contactor coil terminal. See if only one of those fuses blows thus flagging a transient fault condition. If the nuisance trips stop, try a 10A fuse at the bus and remove the test fuses. Bob . . . Un impeachable logic: George Carlin asked, "If black boxes survive crashes, why don't they make the whole airplane out of that stuff?" ________________________________ Message 2 _____________________________________ Time: 08:06:55 PM PST US From: David Saylor Subject: Re: AeroElectric-List: Starter fuse blew x3 I found the problem. There was a short about 6 inches from the fuse block. I let the wire lay up against a sheet metal edge. Thankfully it stopped being intermittent and remained shorted during the search. I'll change the fuse to a 10. Joe, I'm familiar with the instructions for powering SlickStart from the heavy terminal. Years back I had a bad experience doing that. The (new-fangled at the time) permanent magnet starter would make enough voltage spooling down that the retards stayed active. The engine would sputter but never start. Since then I've just always wired them from the control side. Works well. I'd love to hear from others using a PM starter and SlickStart, wired per the instructions. Tough lesson though, and one that's stayed with me. Thanks for everyone's help. --Dave On Sun, Jan 23, 2022 at 12:21 PM Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > At 12:56 PM 1/22/2022, you wrote: > > Thanks Ken.=C3=82 Do you mean the contacts in the solenoid attached to t he > starter?=C3=82 I've replaced the starter in the past but never serviced the > contacts.=C3=82 I can do that. > > The fuse that's blowing isn't in that circuit though.=C3=82 I should cla rify > my terms.=C3=82 The fuse that's blowing powers the starter contactor.=C3 =82 I > called it the starter solenoid.=C3=82 The starter contactor coil has ded icated > external terminals for the coil and isn't associated with the high curren t > starter or solenoid wiring.=C3=82 Cleaning up the solenoid contacts is d oable > but I think my terminology muddied the waters.=C3=82 Or do you think sta rting > current is getting pulled through the starter relay coil? > > > The SlickStart device is basically a capacitor discharge > ignition system with a special feature, instead of delivering > one really hot spark per timing event, it delivers a series > of sparks for each timing event. You can get a peek inside > this critter by reviewing a patent found here: > > https://www.freepatentsonline.com/5630384.pdf > > This is an alternative to the electro-mechanical > 'vibrator' known as "shower-of-sparks" that's been > around for about a century. SOS system use > ship's battery energy conducted through an > electro-mechanical interrupter (vibrator or > buzzer) to deliver a series of energy > pulses into the PRIMARY winding of a magneto > during 'points open' interval immediately following > a spark timing event. This method of spark > generation is not unlike the Kettering points/condenser/ > coil system used on gazillions of cars. The > magneto's primary/secondary windings are used > as a combination energy storage and 'step up' > transformer to convert low voltage, high current > pulses in the primary into a stream of sparks at the > secondary which are conducted out to the plug(s) > by a distributor. > > SlickStart does a similar thing but only uses > the step-up feature of the magneto's magnetics > to convert a stream of capacitor discharges > into the desired high voltage events at the > secondary. > > The SS electronics don't really take much > power as we might guess from the recommended > size of the fuse. I've not yet found the > stated current draw in SlickStart literature > but the patent speaks to something on the > order of 3A consistent with the 5A fuse > callout. > > Intermittent duty contactors can draw upwards > of 3-4 amps themselves. So the combination max > current would push a 5A fuse. I'd design for > 10A in this circuit. > > If one of the two loads is causing nuisance > trips of the fuse, I would suggest the following: > > Put a 15A fuse in at the fuse-bus-block. Put > a temporary 7A fuse in series with the > starter contactor and SlickStart power leads > at the starter contactor coil terminal. > > See if only one of those fuses blows thus > flagging a transient fault condition. If > the nuisance trips stop, try a 10A fuse at > the bus and remove the test fuses. > > > Bob . . . > > Un impeachable logic: George Carlin asked, "If black boxes > survive crashes, why don't they make the whole airplane > out of that stuff?" > ------------------------------------------------------------------------------------- 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.