P-mag 114 and af-2500. Rpm unsteady- Issue resolved!
Installed two p-mag 114’s on IO- 360 with AF-2500 engine monitor. Put the dioxide between ground and pin 6 per instructions on right mag only. Verified pulses set at 4. Engine starts and runs great. Just rpm on AF -2500 bounces all over the place. Verified rpm with prop counter gizmo. When Prop was at 900, tach read 1300. -1500 but never steady. Constantly bouncing around. Any idea what may be going on?
Huge Thank you to Brad Dement of E-Mag and Rob Hickman of Advanced Flight systems. P-mag generates a 12V rpm pulse from pin-6. The Advanced AF-2500 needs a 5V signal. E-Mag provides a diode if receiving unit needs a lower voltage signal. That arrangement produced an unsteady rpm readout. Rob had and sent an Advanced RPM circuit board part #71,420. Essentially it came with a yellow input wire and then a red, white, black output. The yellow went to pin-6 of P-mag. The red, wht and black went to the AF-2500 analogue board. red went to 5V digital, White to the RPM, Black(which I had to slice with a white extension wire) to the common. (see photos) I then removed the diode from P-mag that was between pin 1 & 6. Solution worked like a charm. I installed dual P-mag 114's. Advanced unit only needs 1 input from 1 P-mag. On 2 flights so far: P-mags are awesome! Same profile where i would see 9.9-10 gph, I was seeing high 8's gph, egt's @1300 or less and cht's high 200's to very low 300's. And it starts like opening one of those trick can of peanuts. Thanks again to Rob & Brad.
Installed two p-mag 114’s on IO- 360 with AF-2500 engine monitor. Put the dioxide between ground and pin 6 per instructions on right mag only. Verified pulses set at 4. Engine starts and runs great. Just rpm on AF -2500 bounces all over the place. Verified rpm with prop counter gizmo. When Prop was at 900, tach read 1300. -1500 but never steady. Constantly bouncing around. Any idea what may be going on?
Huge Thank you to Brad Dement of E-Mag and Rob Hickman of Advanced Flight systems. P-mag generates a 12V rpm pulse from pin-6. The Advanced AF-2500 needs a 5V signal. E-Mag provides a diode if receiving unit needs a lower voltage signal. That arrangement produced an unsteady rpm readout. Rob had and sent an Advanced RPM circuit board part #71,420. Essentially it came with a yellow input wire and then a red, white, black output. The yellow went to pin-6 of P-mag. The red, wht and black went to the AF-2500 analogue board. red went to 5V digital, White to the RPM, Black(which I had to slice with a white extension wire) to the common. (see photos) I then removed the diode from P-mag that was between pin 1 & 6. Solution worked like a charm. I installed dual P-mag 114's. Advanced unit only needs 1 input from 1 P-mag. On 2 flights so far: P-mags are awesome! Same profile where i would see 9.9-10 gph, I was seeing high 8's gph, egt's @1300 or less and cht's high 200's to very low 300's. And it starts like opening one of those trick can of peanuts. Thanks again to Rob & Brad.
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