I've noticed that when powering a controller circuit board it seems to be either 5V or 7-35V. Sometimes you even have to change a dip switch or pin connectors when using the 5V. Why is this. One setting seems to handle 5V only and the other setting handles a large range of volts, ie. anything greater than 5V within the range that we commonly use. I guess that maybe the 5V setting handles less than 5V but there are no lights that operate on less than 5V. I figured there must be a reason and there was only one way to find to find out. Thanks.