RPM Pmags

[Setthrust]

I am at a loss, i have a IO-540 C4B5 on a new RV10 and can not get the RPM to be accurate.
i have dual PMAGS , RPM is set at 3 PPR in the EMS. RPM is only connected to one side per the PMAG guide , no resister ( it’s internal per the PMAG guide) . I have set the low pitch blade stop two full turns in ( should lower by 400 RPM) i am still showing an indication of over 2700rpm.
The indication is steady and does not fluctuate abnormally but it’s obviously wrong?

any suggestions?

 

[John Lucas]

I would start by borrowing an optical ROM gauge so you have another source of data to check against what your system is saying. Use that to figure out how far off your RPM readings are and adjust the EMS from there. It took a fair amount of playing around with it to get mine to read satisfactorily accurate, but I have an oddball application (radial engine).

 

[Setthrust]

I would start by borrowing an optical ROM gauge so you have another source of data to check against what your system is saying. Use that to figure out how far off your RPM readings are and adjust the EMS from there. It took a fair amount of playing around with it to get mine to read satisfactorily accurate, but I have an oddball application (radial engine).

Yes i have one and will check it, i am hesitant to change the PPR setting without checking it externally first.

 

[soarhead]

I have dual P-Mags providing RPM information to my HDX on my RV-4. This is a 4 cyl Lycoming. The setting for RPM at the EMS is 2PPR, not 3 but again, that's for the 4 cyl. ( the default setting for the P-Mag is 2, based on the 114 model for 4 cylinder lycomings. ) You can have RPM data coming from both P-Mags. The EMS will simply take the data from the one it sees first. I alternate back and forth on each start up to ensure that both are working. For example, on the first flight of the day, I'll power up the left P-Mag before the right. On the subsequent flight, I'll power up the right first and so forth. It was a simple install with just one wire from each P-Mag wired to the appropriate pin on the EMS. There are several voltage options. I think I wired to the basic 12v or less pin.

 

[Carl_Froehlich]

Perhaps your govenor is still active. I suggest reviewing Vic Syracuse’s video on how to set the low pitch stop.

Carl

 

[Setthrust]

Perhaps your govenor is still active. I suggest reviewing Vic Syracuse’s video on how to set the low pitch stop.

Carl

I did that and follow him a lot

 

[Setthrust]

I have dual P-Mags providing RPM information to my HDX on my RV-4. This is a 4 cyl Lycoming. The setting for RPM at the EMS is 2PPR, not 3 but again, that's for the 4 cyl. ( the default setting for the P-Mag is 2, based on the 114 model for 4 cylinder lycomings. ) You can have RPM data coming from both P-Mags. The EMS will simply take the data from the one it sees first. I alternate back and forth on each start up to ensure that both are working. For example, on the first flight of the day, I'll power up the left P-Mag before the right. On the subsequent flight, I'll power up the right first and so forth. It was a simple install with just one wire from each P-Mag wired to the appropriate pin on the EMS. There are several voltage options. I think I wired to the basic 12v or less pin.

It’s 3 PPR per the 6 cyl install guide and it specifically says only one mag not both.

 

[soarhead]

It’s 3 PPR per the 6 cyl install guide and it specifically says only one mag not both.

Yeah I can see the 3PPR, being a 6 cyl vs 4cyl. Which manual says you should only hook up one RPM source? E-Mag or Dynon? The reason I ask is because in the E-Mag manual that came with mine, Brad clearly states that RPM data is simply a "courtesy" feature. Since I also have the EngineBridge, I can see all the data that the P-Mags are transmitting such as advance angle and temperature. My left one is transmitting corrupt temp data. That could just as easily be corrupt RPM data IMO. Dynon clearly says you can have multiple RPM inputs. Maybe, as a trouble shoot, try taking RPM data from the other Mag and see if the issue remains?

 

[Setthrust]

Yeah I can see the 3PPR, being a 6 cyl vs 4cyl. Which manual says you should only hook up one RPM source? E-Mag or Dynon? The reason I ask is because in the E-Mag manual that came with mine, Brad clearly states that RPM data is simply a "courtesy" feature. Since I also have the EngineBridge, I can see all the data that the P-Mags are transmitting such as advance angle and temperature. My left one is transmitting corrupt temp data. That could just as easily be corrupt RPM data IMO. Dynon clearly says you can have multiple RPM inputs. Maybe, as a trouble shoot, try taking RPM data from the other Mag and see if the issue remains?

 

[jakej]

I am at a loss, i have a IO-540 C4B5 on a new RV10 and can not get the RPM to be accurate.
i have dual PMAGS , RPM is set at 3 PPR in the EMS. RPM is only connected to one side per the PMAG guide , no resister ( it’s internal per the PMAG guide) . I have set the low pitch blade stop two full turns in ( should lower by 400 RPM) i am still showing an indication of over 2700rpm.
The indication is steady and does not fluctuate abnormally but it’s obviously wrong?

any suggestions?

Ok guys, let’s cool it please. The manual says you only NEED ( my emphasis) 1 x rpm output however you can have 1 for each mag if you want .

 

[soarhead]

Cool it? I don't see anyone getting upset. That's the issue with internet forums I guess. Yeah Setthrust, I don't read that as "you must only wire RPM to one PMag." but rather that you "need only wire to one" because the P-Mag will not stop putting out RPM data when you ground it or remove it from ships power. Dynon however, is very clear in that you can wire to both and it will simply read the first one it sees and use the second one if the first fails for some reason. Like I said before, RPM data is not a "supported" feature from E-Mag, so whether you use both or not, I still think that at least trying the RPM data from the other E-Mag is a very simple diagnostic procedure. I have already found corrupt temp data coming from my brand new LH E-Mag, so corrupt RPM data is a possibility. If not, then at least you eliminated it as one.

 

[Setthrust]

Cool it? I don't see anyone getting upset. That's the issue with internet forums I guess. Yeah Setthrust, I don't read that as "you must only wire RPM to one PMag." but rather that you "need only wire to one" because the P-Mag will not stop putting out RPM data when you ground it or remove it from ships power. Dynon however, is very clear in that you can wire to both and it will simply read the first one it sees and use the second one if the first fails for some reason. Like I said before, RPM data is not a "supported" feature from E-Mag, so whether you use both or not, I still think that at least trying the RPM data from the other E-Mag is a very simple diagnostic procedure. I have already found corrupt temp data coming from my brand new LH E-Mag, so corrupt RPM data is a possibility. If not, then at least you eliminated it as one.

Definitely not getting upset or any discord…. Just a discussion
when i was installing i read it differently as don’t install to both, now i suppose it can be interpreted as either one or two.
I got a optical scanner and the RPM is correct at idle and static, i will fly it and see if it’s correct in flight.

 

[Guenin]

My left one is transmitting corrupt temp data. That could just as easily be corrupt RPM data IMO.

The temperature sensor problem is known to both the Emag and EngineBridge folks. I've heard of no similar problems with the RPM reporting (although of course that doesn't mean there aren't any...). But I would put that possibility (the PMag reporting incorrect RPMs) very low on the list. I have dual PMags, and dual Advanced Flight Systems screens, with RPM reporting by each PMag) and I've seen no corrupt RPM reporting in seven years of operation.

 

[Setthrust]

Update , checked with optical scanner and the RPM was indeed correct as shown on the Dynon Efis. Dual Pmags set to 3PPR rpm ,pickup only on one pmag. Adjusted low blade pitch 2.25 turns in and matched the Governor stop to match. All good.

 

[John Lucas]

Update , checked with optical scanner and the RPM was indeed correct as shown on the Dynon Efis. Dual Pmags set to 3PPR rpm ,pickup only on one pmag. Adjusted low blade pitch 2.25 turns in and matched the Governor stop to match. All good.

Congrats on knocking that out

 

[Rhino]

Update , checked with optical scanner and the RPM was indeed correct as shown on the Dynon Efis. Dual Pmags set to 3PPR rpm ,pickup only on one pmag. Adjusted low blade pitch 2.25 turns in and matched the Governor stop to match. All good.

Thanks for coming back and reporting the resolution. That's always helpful to those researching similar or identical problems.