Power Input Panels are generally permanently mounted to the outside of a building. It has to be located so that the associated portable generator is not near any HVAC air intakes for the facility that might draw in the generator exhaust fumes. The portable generator is connected to the Power Input Panel using 4/0 feeder cable with Cam-type Series 16 connectors. The Power Input Panel is permanently connected to a transfer switch (not supplied by Lex) that is used to switch the building electrical supply from domestic power to the portable generator. A transfer switch must be used to switch the building power between the domestic power supply and the generator for safety and to meet NEC requirements.