[cropdusterdave]

Hey folks,

I've been working on getting my RV-7 dialed in and am having a small setup issue with RPM. The indication is way off on the low end. Displaying only about 1700 RPM static at WOT. When I check mag drop...the rt mag only drops 50 or so. However, the lt mag indicates a drop of like 500 rpm...which it is in reality not doing. Thinking I was going to have to mess with resistors, but I started to go through the book and I may have missed one thing. My pulse/revolution settings are off I believe. pins 32 and 34 have a value of 1.5 and 33 and 35 have a value of 3.0. I believe these are supposed to both be set to either 1 or 2. It is my understanding that the lycomings put out two pulses per revolution.....but only the positive is used for rpm? So 1? If it sounds like i'm clueless....it's because i'm clueless.

Setup is a Lyco O-320 with two magnetos. Any advice on the settings?

 

[Raymo]

You should have a resistor installed on each P-lead to the EMS and use 2 pulses per revolution for a 4 banger. The Dynon will use the first RPM sensed from mag that comes online. When doing a mag check, it will use the last mag it senses.

EDIT: You should be using pins 32 and 33 for mag RPM, per the install manual.

 

[Jesse]

What Raymo said. You should have a 30k or higher resistor in-line with the wire going to the p-lead.

1700/1.5=1133*2=2266
1200/1.0=1200*2=2400

Set both at 2 PPR and use the pins recommended and you should be good to go.

 

[cropdusterdave]

Thanks for the help. Hopefully this is a quick and easy fix!