Aerocare - Las Vegas 4490 Delancey Drive, Las Vegas NV 89103 Phone Number: (702) 257-2575
1 Automatically turn generator on and switch power to it when they detect a drop in line voltage; turn generator off when they sense the line power is restored.  Can be used with portable generators as long as the generator has an electric starter.
an intermediate switch is a switch of 4 terminals which is used to control devices from more than 2 locations if you want to control a device eg lamp from one locati on you use a normal switch you could see two terminals behind it