I came across an interesting problem in one of the hobby group discussions - Following problem statement describes the design requirement 1) Input voltage range can be anywhere between 0-500 Volts (It is most likely EV battery pack etc.). They needed a prominent indicator, such as a LED that will illuminate whenever a voltage greater than 60V DC is present across the battery pack. 2) The voltage being present at the connectors must directly control the indicator using hard wired electronics (no software control is permitted). 3) The 0-500V is the only power source available (No external supply / battery can be attached.)
There are 2 design directions I could think - 1) based on TVS diode and a series resistor, which activates an LED after and onward 60 V. 2) Use resistor divider to bring down 0V -> 500V in range of let's say 0 - 5V. I guess even at 500V, if Rdivider value is high as 500K, even a 0.5 W resistor should work. then use any over-voltage detection circuit for LV systems such as this Am I over complicating/ simplifying things here? Critical feedback / suggestions appreciated.