Sunday, May 29, 2016

DC Motor/ Fan Monitoring

DC Motor/ Fan Failure Detection Circuit

It is essential to monitor the health status of fans in some systems to ensure that cooling fans are operating reliably and efficiently. This helps prevent damage to sensitive components and equipment.



Explanation of How the Circuit Works:

Rsense acts as a Fan Current Sensing Resistor with a high power of 30.1W. R1 and C1 establish an average DC level at the midpoint of the transistor of the current waveform and apply this voltage to the base of Q1. Silicon NPN transistors are suitable for Q1.

This DC motor/fan failure detector is designed to detect fluctuations in current through Rsense. It promptly triggers a high output when a static current is detected, effectively signalling a potential failure.

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