Thread: t vago's MPGuino workspace thread
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Old 09-05-2014, 09:26 AM   #393 (permalink)
AndrzejM
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Quote:
Originally Posted by tvcsantos View Post
shed some light and tell me why do wee need to connect a 50k resistor to the vss followed by the 5.1V zener diode....

Thanks,
Tiago
Tiago,

VSS sensor is connected to ECU (in most cases) and to a speedometer, we don't want to alter these readings that's why 50k resistor comes in handy cutting the current it's second role is to secure Zener diode of excesive current. And the diode itself is to cut all the signals that are comming from VSS to Arduino's logics level (5V).

HTH
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