Hi to all, I found this forum by chance whilst was looking for ideas for a project I have in mind . I have a set of daylight running lights working fine using one of these cheap voltage controller (eBay) IE on and off just detecting battery voltage. I have now fitted a solar panel which obviously even when the van if off the voltage on the battery ( during solar charging) can and will increase over the threshold so the lights turn on . I have been thinking how I could detect a sharp voltage increase ( IE engine on) but ignore a slow voltage increase. I know I could use a component like Arduino and with that I could do it just measuring voltage increase against time etc but I wanted to see if was possible to do it without such a components , something simpler ,but so far not come up with any ideas . Anyone would have any though ? Thank you .