Date: Wed, 25 Apr 2001 15:55:17 -0400 From: "Greg Richter" Subject: Re: COZY: Fire warning? / Temp Sensor Solution There's several good ways to get a temperature reading easily for what you're trying to do. National's LM335Z is a TO-92 plastic package (looks like a transistor) that acts like a Zener diode with a steep temperature curve. Put this device in series with a 4.8k Ohm resisitor and measure the voltage from the resisitor/335 junction to ground. It will be in millivolts, and correspond to degrees Kelvin. Cheap, effective and works great. I'm using one for an OAT sensor potted in shrink tubing and another for cowling air temp. The good news is that you end up with a 2.8 volt signal at ambient air temps, which is easy to drive a meter, bell or canon annunciator with. You can get them from Allied Electronics on-line at http://alliedelec.com Hope that helps! -GR Greg Richter Cozy N722 Mazda 13B Turbo http://bluemtn.com/greg At 10:21 AM 4/24/2001 -0500, Epplin John A wrote: >Builders, > >I have the AV10 engine monitor and warning system. Finishing installation >details at the moment. This unit has inputs for 8 cylinders, either as a >twin engine or up to 8 cylinder engine. Using a O-360 leaves several >thermocouple inputs unused. Two of these have been robbed for wheel brake >heat shield temp measurement. I am not sure what this will tell me but the >cost was near nothing, I used very fine thermocouple wire and put a 1/16 in >Teflon tube in the gear when I put in the brake conduits. I intend to >attach this thermocouple to the gear strut between the heat shield and the >fiberglass/epoxy strut with a bit of RTV. Will report what I find during >the test flight phase. I am at an airport with over 10,000 ft runway so a >long crosswind taxi is probable sometime. > >This leaves 4 type K and 2 type J thermocouples to play with. All the >hardware is in place except the actual wire so the cost in both dollars and >pounds would be minimal for any use these could be put to. Each channel can >be set to alarm and/or display the reading. My thought is to place a >thermocouple at the cooling air exit on each side of the engine. Just clamp >it to the pushrod tube or maybe to the cylinder head baffle. The >thermocouple would be nothing but resistance welding the wires together of >some small type K wiring. Another potential placement would be somewhere >around the Ellison TB unit, don't know where would be the most effective >location there. Also thought of placing one on the alternator frame. This >might be a good idea during the initial test flights to verify that it is >cooling OK. > >Does anyone have any ideas, suggestions etc.? Keep in mind that the cost is >minimal and if the readings are set to alarm only, distraction to the pilot >is minimized. I can visualize a broken exhaust pipe causing a change in the >air outlet temp before any other indication. Would be nice to have some >warning. > > >John Epplin.. Mk4 #467 N100EP Date: Wed, 25 Apr 2001 16:38:28 -0400 From: "Greg Richter" Subject: COZY: EFIS Kit Available Enough people have asked about a parts kit for my EFIS that I've got one together. If you are interested in an EFIS in your Cozy like the one we in my three place, take a look at my home page: http://bluemtn.com/greg or the more professional one I just finished at: http://bluemountainavionics.com Thanks! -- Greg Richter can usually be found in the North Carolina mountains searching for wild mushrooms, honey trees or small hydroelectric sites. Emails are best served with an old Madeira or Armagnac which greatly increases the chance of a speedy or useful reply. Cozy N722 -- Mazda 13B Turbo http://bluemtn.com/greg