I posted this on RCGroups, but thought I would try hear also.
I installed a FrSky SP-RPM - Smart Port RPM and Dual Temperature Sensor in my plane and find the RPM's to be off by over a thousand. I have the poles set correctly for my motor and the blade numbers in the set up correct. My motor has 12 poles, so I set the LED's for 6 pair and the blade count to one for a 2 blade prop. When I run the motor up to half stick, my read out on the transmitter reads 7600. When I check it with an optical tach known to be accurate, it reads around 6500. That is a big difference. At full throttle it is almost 1550 RPM difference. Can these things be calibrated or is this as accurate as they are?
This a Taranis Plus tx and a S8R rx. Any thoughts. Sam
I installed a FrSky SP-RPM - Smart Port RPM and Dual Temperature Sensor in my plane and find the RPM's to be off by over a thousand. I have the poles set correctly for my motor and the blade numbers in the set up correct. My motor has 12 poles, so I set the LED's for 6 pair and the blade count to one for a 2 blade prop. When I run the motor up to half stick, my read out on the transmitter reads 7600. When I check it with an optical tach known to be accurate, it reads around 6500. That is a big difference. At full throttle it is almost 1550 RPM difference. Can these things be calibrated or is this as accurate as they are?
This a Taranis Plus tx and a S8R rx. Any thoughts. Sam