---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 12/24/20: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:07 AM - automatic switch (GLEN MATEJCEK) 2. 04:31 AM - Re: automatic switch (C&K) 3. 05:36 AM - Re: automatic switch (Robert L. Nuckolls, III) 4. 06:06 AM - Re: automatic switch (Ken Ryan) ________________________________ Message 1 _____________________________________ Time: 04:07:30 AM PST US From: GLEN MATEJCEK Subject: AeroElectric-List: automatic switch >That's fine, but if it's 'automatic', that implies that it can switch over >and begin consuming power off the backup(s) whether you're there to 'load >shed' or not. Just something to think about. I have been contemplating some of these issues off and on for a while. One option would be to put all essential loads on one phase of the main panel. Have adequate wiring to a heavy duty 120v receptacle on a dedicated breaker on that phase. When the power fails, trip the main breaker and plug a portable generator into the dedicated receptacle. No load shedding required, just about as simple as can be, and probably not more than $20 in parts. FWIW- ________________________________ Message 2 _____________________________________ Time: 04:31:43 AM PST US Subject: Re: AeroElectric-List: automatic switch From: C&K While these manual schemes work well somebody should mention that they are illegal almost everywhere due to the risk of back feeding power to the utility and electrocuting a lineman by mis handling the main breaker. It happens which is why a double throw main breaker arrangement is mandated. Ken On 24/12/2020 7:01 AM, GLEN MATEJCEK wrote: > >That's fine, but if it's 'automatic', that implies that it can switch > over > >and begin consuming power off the backup(s) whether you're there to 'load > >shed' or not. Just something to think about. > > I have been contemplating some of these issues off and on for a > while. One option would be to put all essential loads on one phase of > the main panel. Have adequate wiring to a heavy duty 120v receptacle > on a dedicated breaker on that phase. When the power fails, trip the > main breaker and plug a portable generator into the dedicated > receptacle. No load shedding required, just about as simple as can > be, and probably not more than $20 in parts. > FWIW- ________________________________ Message 3 _____________________________________ Time: 05:36:58 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: automatic switch At 06:27 AM 12/24/2020, you wrote: > >While these manual schemes work well somebody >should mention that they are illegal almost >everywhere due to the risk of back feeding power >to the utility and electrocuting a lineman by >mis handling the main breaker.=C2 It happens >which is why a double throw main breaker arrangement is mandated. Yup, that's why there is a check-list for transitions between mains and generator . . . but failure to disconnect ac mains would result in immediate operation of the generator's breakers. 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 4 _____________________________________ Time: 06:06:08 AM PST US From: Ken Ryan Subject: Re: AeroElectric-List: automatic switch The essential loads that I need to run are boiler, unit heater, well pump and refrigerator/freezer and hangar door. Given that this is at least 90% of the total amperage and a good percentage of the circuits, I believe powering the whole building is what makes sense. And I definitely agree that the system must not allow for feedback to the grid through operator error. Ken On Thu, Dec 24, 2020 at 4:41 AM Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > At 06:27 AM 12/24/2020, you wrote: > > > While these manual schemes work well somebody should mention that they ar e > illegal almost everywhere due to the risk of back feeding power to the > utility and electrocuting a lineman by mis handling the main breaker.=C3 =82 It > happens which is why a double throw main breaker arrangement is mandated. > > > Yup, that's why there is a check-list for > transitions between mains and generator . . . > but failure to disconnect ac mains would > result in immediate operation of the generator's > breakers. > > > 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.