I've had a PD4135 installed recently to replace the original converter in my Trillium
4500. The old one had a 3-way switch on it for Off, 12V and 120V. Is there a similar switch on the PD4135. Or is it ON all the time? If I'm plugged into Shorepower, how does it know to switch from the battery
power? (I have a battery
in the trailer- on the bumper).