N601RX Posted October 2, 2015 Report Share Posted October 2, 2015 (edited) I've installed the Omegadyne MP transducer specified in the drawings (PX329-030AV), and the MP only reads 14" at our 5000ft elevation with the engine off. I suspected a bad transducer, but Omegadyne's tech support said this transducer is PSIA (A=absolute pressure, not inches of mercury), and that the 14" I'm seeing is the correct output for my elevation in terms of absolute pressure. I've tried adjusting the pot on the side of the Moritz panel, but it only changes the reading by a couple of tenths, not 11". The connector wiring has been checked and is correct. I don't have a complete set of the drawings (just the pages posted by N1026F) or the cover letter, so am I missing something? Do I have a bad Moritz panel? (God forbid!) Any help would be appreciated. 5000' is about 12.2psi of absolute gauge. The omega sensor has a range of 0 to 30 psia that is represented by a output signal of 0 to 100 mv per their data sheet. This would mean that at your altitude of 5000' the sensor should be putting out around 40 mv which you should be able to measure with a meter and determine if the transducer is functioning correctly. Also verify that the gauges are supplying the sensor with 10vdc. Edited October 2, 2015 by N601RX Quote Link to comment Share on other sites More sharing options...
DaveC Posted October 2, 2015 Report Share Posted October 2, 2015 N601RX, Thanks for the info. I have measured the in/out voltages. In from the Moritz panel was just a shade under 10vdc. Output was 31mv, which I thought was low based on the test sheet sent with the transducer - should be about 44mv. Omegadyne tech people are claiming that the reading I'm getting is low because I'm using the wrong type of meter to read the output voltage. Bottom line is that since this is the transducer (supposedly) vetted by Mooney, it should work properly. Quote Link to comment Share on other sites More sharing options...
N601RX Posted October 2, 2015 Report Share Posted October 2, 2015 (edited) 31mv would be too low, but it's possible that the signal is being pulled down by the gauge . Try disconnecting the two signal wires and measure the voltage on them while they are not attached to anything. If it's still at 31mv while the excitation voltage is at 10vdc then the sensor isn't functioning correctly. Note that the sensor says its ratiometric and the 100mv output at full scale is based on 10vdc being supplied as the exication voltage. If the excitation voltage dropped to 5vdc then the output range would drop proportionally to 0-50 mv. According to the prints posted earlier the mv signal should be read across the green and yellow wire. As long as your using a digital meter it will have an input impedance high enough hot to affect the reading. If your using an analog meter, many of them have a low input impedence and can make the reading appear lower than it really is. Edited October 2, 2015 by N601RX Quote Link to comment Share on other sites More sharing options...
DaveC Posted October 2, 2015 Report Share Posted October 2, 2015 I will go out this weekend and disconnect the signal wires to see what the output is without the green/yellow lines to the Moritz panel connected. I am using a fairly cheap handheld digital VM from Radio Shack. Output from the Moritz panel on the Red/Black power lines was 9.7vdc, so it shouldn't significantly affect the output. Quote Link to comment Share on other sites More sharing options...
carusoam Posted October 7, 2015 Report Share Posted October 7, 2015 Follow up... I was reading a JPI manual today... They have a procedure for setting the constants related to MAP. It would make sense if you were to change sensors, you would want to follow the calibration procedure outlined in the book related to your display. They indicated a few inches of adjustment are possible. Just another idea, -a- Quote Link to comment Share on other sites More sharing options...
DaveC Posted October 7, 2015 Report Share Posted October 7, 2015 The Moritz panel also has an adjustment pot for MAP. Unfortunately, it only adjusts the MAP about .5" total, so it doesn't correct the 10" error. I have another transducer coming tomorrow or Thursday, so that will tell me if it's the transducer or the Moritz panel. If the new transducer works, I'm home free. If it's the Moritz panel, I will probably look at a new engine monitoring system from EI or JPI and cough up the big bucks to eliminate the problem of unavailable/unsupported parts in my 2001 Ovation engine/fuel/electrical indication system. Thanks for all your suggestions. Dave Quote Link to comment Share on other sites More sharing options...
carusoam Posted October 7, 2015 Report Share Posted October 7, 2015 Dave, have you seen this Moritz support thread? It may be helpful to initiate contact with the company listed for support. Best regards, -a- Quote Link to comment Share on other sites More sharing options...
DaveC Posted October 8, 2015 Report Share Posted October 8, 2015 I received another transducer yesterday from Omegadyne, and it isn't much better than the first one. This one shows 19" at 5000' vs. 14" for the first one I installed. Still can't adjust the Moritz panel enough to get to 25" here at 5000'. I'm suspecting the MAP part of the Moritz panel has gone bad, and will investigate repairing the Moritz or replacing it with a JPI or EI primary engine monitor. A JPI or EI engine monitor is probably the best idea for the long run due to the limited support offered by Radiant Power Corp. and Mooney. Unfortunately, that will involve a new panel and a lot of planning, but at least it should be supported for the foreseeable future. Quote Link to comment Share on other sites More sharing options...
jmillerk Posted July 26, 2018 Report Share Posted July 26, 2018 Just reading these old posts regarding the MAP retrofit. Currently having an issue with my MAP transducer in my Eagle. Now reads 6.0"hg too low. Removed my Moritz cluster today and there is not a potentiometer for adjusting the MAP like shown in the retrofit drawings. Anyone know if there is a remote potentiometer or adjustment place somewhere else? Thanks. Quote Link to comment Share on other sites More sharing options...
DaveC Posted July 26, 2018 Report Share Posted July 26, 2018 My Moritz engine instrument cluster had a small hole on the side of the case covered with a piece of silver tape. If I remember right, it was on the right side, but mine was from my Ovation, don't know if the Eagle part is the same. Good Luck! Dave Quote Link to comment Share on other sites More sharing options...
Gary R. Jones Posted July 27, 2018 Report Share Posted July 27, 2018 On 3/10/2015 at 11:07 PM, chrisbre said: Looking for the above part for a TLS Bravo . Estimated delivery time at Mooney is 275 days, but I can't wait till 2016 to get the Mooney in the air again! Thanks for your help! On Mooney Space I have a used transducer, working transducer for $325 if interested. Quote Link to comment Share on other sites More sharing options...
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