Review on Waterproof HM1 Inductive Hour Meter: Perfect for Gas Engine Lawn Mowers, Dirt Bikes, Motorcycles, Snowmobiles, ATVs, Boats, Outboard Motors, Generators, and More! by Hunter Siemon

Love the low price and the great idea. However, I bought it in the hope that it would work in my relay coil activation monitoring application. Since the description didn't have enough information, I took a chance to try it since the price was low. I just wanted to observe how long the 12 volt relay took to activate, so I wrapped a long sensor wire around the relay coil several times. However, it seems that more tension is required in the spark plug wire. Sometimes I could briefly activate it while bathed in a fluorescent light. It would be great to have a product that could be powered from a high voltage source other than just induction. For example by connecting directly to a 12V or even 5V source.