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Skybolt
01-11-2017, 02:48 PM
I have a 2500 I'm installing in my plane and it only has one RPM sensor, how can I hook one up to both mags so I can watch RPM drop?

Shawn McGinnis
01-11-2017, 05:31 PM
They both remain spinning so you just place the sensor in the non-impulse mag.

Skybolt
10-10-2017, 07:12 AM
They both remain spinning so you just place the sensor in the non-impulse mag.

I have the same question. Where do you hook up the second sensor to? Double up the wires in the RPM slot of the analog module??

Shawn McGinnis
10-10-2017, 09:00 AM
Only one sensor is used in a dual mag setup.

Skybolt
10-11-2017, 09:30 AM
Only one sensor is used in a dual mag setup.

I guess I'm not being clear; My engine has two separate magnetos, not a dual drive. single magneto.

There is only one place to put wires in the analog module.

Shawn McGinnis
10-11-2017, 09:44 AM
Correct, you will use one sensor in your right mag wired to the analog module. The mags continue to turn, even if they are grounded, providing RPM on both, left, or right settings.

Skybolt
10-12-2017, 08:56 AM
Correct, you will use one sensor in your right mag wired to the analog module. The mags continue to turn, even if they are grounded, providing RPM on both, left, or right settings.

Having only RPM from the right mag will preclude doing a mag check during preflight as I will not have RPM for the second mag.....

Shawn McGinnis
10-12-2017, 11:59 AM
Are you seeing this on your mag check procedure? Because you are the first aircraft in our 20 years that it doesn't work this way.

If your engine is running both mags are spinning on the same gear. If they are spinning on the same gear then the magnet attached to the shaft on both mags must pass by the hole use use for RPM pickup no matter which mag you place the sensor on. Grounding the mag just keeps the coil from building charge and has nothing to do (besides keeping engine running) with the RPM output.

Skybolt
10-17-2017, 02:03 PM
Are you seeing this on your mag check procedure? Because you are the first aircraft in our 20 years that it doesn't work this way.

If your engine is running both mags are spinning on the same gear. If they are spinning on the same gear then the magnet attached to the shaft on both mags must pass by the hole use use for RPM pickup no matter which mag you place the sensor on. Grounding the mag just keeps the coil from building charge and has nothing to do (besides keeping engine running) with the RPM output.

I'm an idiot. 38 years as a mechanic and I ask this stupid question. Sorry to waste your time. I was overthinking the problem.....