EMS -220 Type A Contacts

VH-IEW

I love flying!
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Oct 6, 2015
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I am unsure what is meant by "Contacts" I assume this means a change of state on the sensor wire. Can a type "A" sensor input accept and drive a widget on a change from 0 volts to 12 volts DC confirming that a device ie fuel pump is switched on?
 

dynonsupport

Dynon Technical Support
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Ian:

A contact might be more conventionally known as a "switch or relay close or open". Or the presence or absence of a voltage.

Yes, a Type A General Purpose Input configured as a contact can display the presence or absence of 12V... but understand that if the voltage on that input is > 15V, the input can be damaged. The more conventional (safe) way to use a contact is for a switch closure or opening, or a voltage level of 5V.

I am unsure what is meant by "Contacts" I assume this means a change of state on the sensor wire.   Can a type "A" sensor input accept and drive a widget on a change from 0 volts to 12 volts DC confirming that a device ie fuel pump is switched on?
 

VH-IEW

I love flying!
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Oct 6, 2015
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Could I install a resistor in series to drop the voltage as a safety measure? If so what value should the resistor be?
 

dynonsupport

Dynon Technical Support
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The inputs are designed to be safe in a 12V airplane, which means 15V normal operation with load dump spikes to 30V. Unless you are actually running a device that can generate more than 15V, you don't need protection.

You can hook it right to the fuel pump power wire and it should do what you expect safely.
 
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