---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 03/05/12: 9 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:43 AM - Re: Coolie Hat Switch (Etienne Phillips) 2. 06:00 AM - Re: Coolie Hat Switch (Robert L. Nuckolls, III) 3. 09:43 AM - Re: Coolie Hat Switch (Peter Mather) 4. 01:44 PM - Fw: Coolie Hat Switch (Buckley William) 5. 05:02 PM - Re: battery chargers (Robert L. Nuckolls, III) 6. 05:07 PM - Re: Fw: Coolie Hat Switch (Robert L. Nuckolls, III) 7. 05:30 PM - Re: battery chargers (Robert L. Nuckolls, III) 8. 06:46 PM - HID EMC update (Robert L. Nuckolls, III) 9. 07:29 PM - OT: Old electronics info. (rayj) ________________________________ Message 1 _____________________________________ Time: 04:43:00 AM PST US Subject: Re: AeroElectric-List: Coolie Hat Switch From: Etienne Phillips **On 5 March 2012 06:50, wrote: > > Does anyone have a source for a roll your own coolie hat switch? > Hi Sam Not cheap, but available from RS Components... *http://tinyurl.com/6u8ephu * Hope that helps! Etienne* * ________________________________ Message 2 _____________________________________ Time: 06:00:22 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Coolie Hat Switch At 10:50 PM 3/4/2012, you wrote: > >Does anyone have a source for a roll your own coolie hat switch? I would think you'd need access to some pretty good machine tools and a good bit of patience. Not sure DIY is very cost effetive. Ray-Allen has one http://www.rayallencompany.com/products/switches.html Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________ Message 3 _____________________________________ Time: 09:43:36 AM PST US From: "Peter Mather" Subject: RE: AeroElectric-List: Coolie Hat Switch Cheapest way of getting one is using an electric wing mirror switch from a car breakers or ebay ________________________________ Message 4 _____________________________________ Time: 01:44:25 PM PST US From: Buckley William Subject: Fw: AeroElectric-List: Coolie Hat Switch Take a look at these from Digikey ($22.50 each) http://search.digikey.com/us/en/products/500-526/679-2289-ND/2063280 William B. --- On Sun, 3/4/12, sam.marlow@roadrunner.com wrote: > From: sam.marlow@roadrunner.com > Subject: AeroElectric-List: Coolie Hat Switch > To: "aeroelectric-list@matronics.com" > Date: Sunday, March 4, 2012, 11:50 PM > --> AeroElectric-List message > posted by: > > Does anyone have a source for a roll your own coolie hat > switch? > > AeroElectric-List Email Forum - > - MATRONICS WEB FORUMS - > List Contribution Web Site - > -Matt > Dralle, List Admin. > > > > ________________________________ Message 5 _____________________________________ Time: 05:02:36 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: battery chargers At 07:41 AM 3/4/2012, you wrote: > >Hi Bob, > >The explosion I mentioned was in reference to a flooded battery, not >an Odyssey. I once put a charger on my tractor and forgot about >it. A few weeks later I found part of the battery case about 10 >feet from the tractor. The rest of the battery was still in the >tractor battery box with the innards showing! I assume that when >the electrolyte got below the top of the plates that some conductive >debris shorted between them and set off the oxygen/hydrogen >explosion. This experience has caused me to be leery of battery >tenders. This could happen with even a 1/2 amp charger because the >energy that makes the spark comes from the battery, not the charger. > >Thanks for the excellent information in your post on battery chargers. Oh yeah . . . I've seen flooded batteries do a steam explosion . . . or more like a volcano eruption too. A good friend of mine worked in the Naval Battery Labs at Crane, IN. Those labs are a kind of battery-hell. Many folks (especially submariners) wont qualify a battery until Crane sez, "they can't blow it up." She sent me some videos of some rather spectacular 'batterycides'. I am aware of only one in-service RG battery explosion. It was a new model Concorde being qualified onto a GA jet. This particular battery had been subjected to some severe conditions of overcharging followed by a couple of spool-ups (no ignition or fuel) on the airplane. The evolved gasses combined with some simulated balked starts fused a cross-over joint between cells . . . Emacs! Concorde's crossovers are soldered on by hand . . . Emacs! . . . and set high enough on the cell wall to become immersed in epoxy encapsulant which is used to fill the inter-cell sealing channels in the lid . . . Emacs! Interestingly enough, this battery design had already been qualified to the RTCA/TSO requirements . . . which seem not to stress a battery as hard as in the incident aircraft. Even though analysis of the event said it was not necessary, Concorde did beef up the inter-cell connectors in that model of battery. We have been apprised of an incidence of a high-energy, internal event on a Hawker 10 AH 24V battery . . . Emacs! Temperatures were so high as to severely char the internals Emacs! . . . I think this event stayed inside the battery case except for one small hole. I wasn't informed of the history of this even but given the battery's small size (10 a.h.) and the size of the typical 24v alternator (60A) I'm betting that the short term high recharge rates for this battery were exceeded causing a failure of the one cell. The RG or SVLA battery has amassed a long history of robust service and few exceptions for more than benign failures . . . and they get better all the time. Bob . . . ________________________________ Message 6 _____________________________________ Time: 05:07:32 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: Fw: AeroElectric-List: Coolie Hat Switch At 03:42 PM 3/5/2012, you wrote: > > >Take a look at these from Digikey ($22.50 each) > >http://search.digikey.com/us/en/products/500-526/679-2289-ND/2063280 Cool find Bill . . . these are electrically 'delicate' switches. Rated 1 to 50 mA. They should be used to control a solid-state buffered relay deck but they look pretty slick. Bob . . . ________________________________ Message 7 _____________________________________ Time: 05:30:02 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: battery chargers At 11:40 AM 3/4/2012, you wrote: > >During charging, offgases are produced. If those gasses collect >somewhere, a spark can indeed set them off. Yes, thay can collect >inside the battery itself. Several RV batteries have been blown up >that way so I assume that it happens all over the place. Happened >to me once and my battery compartment is well ventilated. > >David M, Was there any sort of failure analysis done? Pictures taken? An RG battery stressed so hard as to produce gasses not contained in the mats combined with some spark-producing condition begs for answers as to root cause. I would be reluctant to assume that it 'happens all over the place' . . . yours is the first mention of explosive de-construction of a battery here on the List in many years. I was aware of a battery box explosion in a GlasAir wherein the battery box provided containment and a battery contactor provided ignition. But even that event was poorly documented and no mention was made of what was probably a sustained OV event that cooked the battery. Somebody sent me an abused Odyssey some years back, Dec 2005 I think. I sent it to Concorde and their guys tore it down for closer examination. In this case, the battery case was intact. The battery had be subject to an OV condition which heated the battery up while building large sulfation crystals on the normally thin plates. The thing puffed up like a guppy. Emacs! Emacs! RG batteries are not designed to withstand severe over-charging or extra-ordinary stress such as that which produced the one real explosion I'm aware of. After running the gauntlets at TSO or Naval qualification labs, they are shown to offer benign failure events when used in a system with legacy attention paid to rapid mitigation of an OV event. If anyone becomes aware of what appears to have been an explosive rupture of an RG battery, please let me know about it ASAP. I'll pay for pictures, a narrative of conditions leading up to the event and pay the shipping for the carcass. These things need to be examined by folks who are very good at it so as to broaden our understanding and improvement on the best we know how to do. Bob . . . ________________________________ Message 8 _____________________________________ Time: 06:46:45 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: HID EMC update Had a meeting today that promises to renew a relationship with folks at National Institute of Aviation Research (NIAR) on the campus of Wichita State University. They are the proud possessors and operators of an extensive and up-to-date EMC lab. Guys I used to work with at HBC are now at NIAR. I'll be looking for an opportunity to get a radio-peek at the two exemplar HID lamps I've been provided. We'll do conducted emissions on the power supply wires in addition to a probing exploration of light's noises on a spectrum analyzer. Watch this space . . . Bob . . . ________________________________ Message 9 _____________________________________ Time: 07:29:54 PM PST US From: rayj Subject: AeroElectric-List: OT: Old electronics info. Greetings, I have an Acme Voltrol type T-2-1404 variable transformer I'm using to set up a power supply for my bench. Can anyone tell me where I can get the max Amps or VA rating for it? I also have a big red rectifier that is about a 6" cube of fins and an inductor that is the size of a softball and weighs >10lb. Neither have any identifying marks on them. Any sources where I can find info on these things would be appreciated. do not archive Thanks in advance, -- Raymond Julian Kettle River, MN "And you know that I could have me a million more friends, and all I'd have to lose is my point of view." - John Prine ------------------------------------------------------------------------------------- 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.