---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Fri 03/11/22: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:35 AM - Z101b with Shunts, Shunts as Fuse Link Junctions (Jared Yates) 2. 10:50 AM - Re: Z101b with Shunts, Shunts as Fuse Link Junctions (Robert L. Nuckolls, III) 3. 12:53 PM - Z101b Wire Gauge question (Jeffrey Cohen) 4. 01:17 PM - Re: Z101b with Shunts, Shunts as Fuse Link Junctions (David Carter) 5. 04:47 PM - Re: Z101b with Shunts, Shunts as Fuse Link Junctions (user9253) ________________________________ Message 1 _____________________________________ Time: 10:35:03 AM PST US From: Jared Yates Subject: AeroElectric-List: Z101b with Shunts, Shunts as Fuse Link Junctions Z101b has a very nice implementation of a single Hall Effect sensor for both alternator B-leads. The trouble I have is that I don't have an ammeter that can use a Hall Effect sensor. I can see a few options. One is to install two shunts and use a DPDT switch to select which one presents on the ammeter. If I go this route, is it kosher to integrate the alternator B-lead fuse link at the shunt? For example, for the main alternator, can I run an 8g wire from the alternator to one end of the shunt, then on the other end of the shunt, run a 4" piece of 12g wire to the starter contactor? The same strategy would work for the standby alternator, with slightly different numbers and attach points. Another option is to seek out a stand-alone ammeter that senses with a Hall Effect Sensor. But that is likely to be more expensive and more work to integrate at this stage. Is there such a thing? Thanks! Jared ________________________________ Message 2 _____________________________________ Time: 10:50:19 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Z101b with Shunts, Shunts as Fuse Link Junctions At 12:34 PM 3/11/2022, you wrote: >Z101b has a very nice implementation of a single >Hall Effect sensor for both alternator B-leads. >The trouble I have is that I don't have an >ammeter that can use a Hall Effect sensor. > >I can see a few options. One is to install two >shunts and use a DPDT switch to select which one presents on the ammeter. =C2 That's how walter beech did it >If I go this route, is it kosher to integrate >the alternator B-lead fuse link at the shunt? >For example, for the main alternator, can I run >an 8g wire from the alternator to one end of the >shunt, then on the other end of the shunt, run a >4" piece of 12g wire to the starter contactor? >The same strategy would work for the standby >alternator, with slightly different numbers and attach points. > >Another option is to seek out a stand-alone >ammeter that senses with a Hall Effect Sensor. >But that is likely to be more expensive and more >work to integrate at this stage. Is there such a thing? Probably, but yeah not for price of a big-mac and fries. Consider putting the ammeter in ONLY the stand-by alternator. You've done a load analysis . . . yes? Your main alternator is at zero risk for being over taxed. The S/B alternator is limited and would benefit most from in flight knowledge of present loads. But it's still not a flight critcal item. Your plan-b load shedding protocols were all established during load analysis . . . yes? You can't overload it at vacuum pump drive pad speeds. If you did tax beyond capability to sustain bus voltage, you'll see it on the lo volts warning and even before, observe it on the panel volts display. Panel ammeters are about as useful as foxtails on your '57 Chevy's radio antenna. Looks cool but adds no utility. Greatest use for ammeters is ground diagnostics and there are other ways to get that data. I included that feature only because the glass- cockpit guys include in their products. Why? Cause they can for very little cost . . . and it's cooler than a foxtail hanging off your VHF COMM antenna. If it were my airplane, I'd do the operational protocols planning, proof them in flight testing then rely on active notification of low volts. Ammeters need not apply. 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 3 _____________________________________ Time: 12:53:59 PM PST US From: Jeffrey Cohen Subject: AeroElectric-List: Z101b Wire Gauge question Thank you for the previous reply post on Fusing. Very helpful. Now for a wire gauge question. On Z101b, is there a reason that a 12AWG wire feeds into the NTE53016 Diode, but a 14AWG wire leads out? Jeff Cohen Jcohen@post.com 734-323-7421 ________________________________ Message 4 _____________________________________ Time: 01:17:52 PM PST US From: David Carter Subject: Re: AeroElectric-List: Z101b with Shunts, Shunts as Fuse Link Junctions I included that feature only because the glass- cockpit guys include in their products. Why? Cause they can for very little cost . . . One thing I've learned as I'm finalizing the avionics interconnects on my Garmin G3X panel: general-purpose analog-to-digital inputs can be a scarce commodity, depending on your needs. They are only available on the GEA 24 Engine Indication System box, and there are only 7. (There are separate dedicated Shunt 1 & Shunt 2 inputs available.) Someone might choose a shunt over the Hall-effect sensor to free up an A/D input channel. Or go without current measurement as Bob suggests. How could you run out of general-purpose A/D inputs? 1 - elevator trim position sensor 2 - aileron trim position sensor 3 - rudder trim position sensor 4 - flaps position sensor 5 - exhaust O2 sensor 6 - timing advance from electronic ignition 7 - bus 1 Hall effect current sensor 8 - bus 1 Hall effect current sensor 9 - cabin CO monitor 10 - pilot SPO2 monitor 11 - O2 bottle pressure sensor etc. In my configuration, I'll have the following: 1 - elevator trim position sensor 2 - flaps position sensor 3 - exhaust O2 sensor 4 - timing advance from electronic ignition 5 - Main/Aux alternator current Hall effect sensor 6 - cabin CO monitor 7 - spare (who knows what I'll come up with in the future!) I'll monitor O2 bottle pressure, pilot blood oxygen level, outside humidity, and outside dewpoint values via an app on the iPad. (all via products from Aithre) --- David Carter david@carter.net > ________________________________ Message 5 _____________________________________ Time: 04:47:43 PM PST US Subject: AeroElectric-List: Re: Z101b with Shunts, Shunts as Fuse Link Junctions From: "user9253" An ammeter is optional. As long as the voltage is above 13.5, you will know that the alternator is working. The pilot does not need to know how many amps the alternator is putting out. It is useful to know current for troubleshooting purposes. Save troubleshooting for when safely on the ground using a handheld meter. If desired to know amps while airborne, install a shunt on the standby alternator to help manage loads. There is no need to know amps while the primary alternator is working. What kind of EFIS are you going to install? If none, have you considered a GRT EIS Engine Monitor? I believe it works with a HALL effect sensor. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=506293#506293 ------------------------------------------------------------------------------------- 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.