EMS GP voltage and ammeter questions

[Danerazz]

For the GP pins used in “contact” mode to sense things like gear position, pitot heat, etc; in a 28v system is the recommended 10KOhm resistor adequate to protect the system? Manual is kind of ambiguous (looks like it should…)

Second question: I need three ammeters: two aircraft load meters (twin engine) and prop A/I amperage. Can I display all three (all would have to be GRT hall-effect, I need 2x 100A and one 20-30A range and the shunts are only 60A)? The manual says the GRT can be substitutes for the shunts, but doesn’t say anything about “extra” load meters.

 

[Rhino]

For the GP pins used in “contact” mode to sense things like gear position, pitot heat, etc; in a 28v system is the recommended 10KOhm resistor adequate to protect the system? Manual is kind of ambiguous (looks like it should…)....

Sort of depends on how many contacts you use. This might help;

12V On/Off Inputs

My searches have helped educate me a little but I just wanted to confirm what I think I know by asking the question, without suggesting an answer.......this is my way of saying I have done some research :) I have two, separate, units that 'produce' 12V output when triggered. One is a low fuel...

forum.flydynon.com

 

[Danerazz]

The math on the voltage divider works on 14v, but if it is a 28v system should the resistors should be adjusted to get approximately 5v at the pin? The manual doesn’t say that…

 

[Rhino]

Go to 20k ohms. If you have more than one such input, you may need to increase it even more. But the pins already have about 5 volts of bias on them. You can't simply connect 28 volts to make it work. You're technically switching a ground connection to it. Read the thread I linked carefully.