What feature would the power management module add to the generator?

The Generac rep's answer is 100% correct, but here's "the bottom line" answer... it allows you to buy a much smaller generator and still pass inspection with your local building/electrical inspector. For a whole-house generator, an electrician must measure or estimate every electrical load in your house. The generator is then "sized" to safely handle a 100% electrical load, AS IF YOU WILL HAVE EVERYTHING IN YOUR HOUSE POWERED-ON ALL AT THE SAME TIME DURING A POWER OUTAGE. Generac's power management (this starter kit) allows you to wire certain high-amperage loads (like your A/C, clothes dryer, etc.) where they are on a delayed start-up (no problem), and can also be turned-off (load shedding) ONLY IF NECESSARY so that the generator is not overloaded. Here is the practical application: let's say that the electrician's load measurement for your entire home results in the need for a 20 kw generator. You could buy a 20 kw generator, and this would allow you to have every light, every cooking appliance, washer and dryer, radio, vacuum, even your A/C and heat all turned on at the same time during a power outage. But that would be crazy, you know you're not going to be doing all of that during a power outage! So, you install power management on a few of your largest electrical appliances - let's say your air conditioner, electric water heater, and clothes dryer - and this legally and safely allows you to install a much smaller generator. The smaller generator costs less up-front, costs less to maintain, and uses less fuel when it's running, so it really is a win-win-win situation to do this. And, realistically, the load shedding may never be activated... unless you go wild and run lots of electrical appliances while on generator power!

Generac manufactures multiple automatic standby generators that feature load shedding capabilities. For example, the 20kW automatic standby, when paired with a Smart Switch transfer switch, will have load shedding capabilities. The Smart Switch has a load shed module that will handle up to six larger loads with the use of the pre-designated contacts, two of which are designated for air conditioner units. The (2) air conditioner contacts will be connected via the 24v low voltage thermostat wires for your air conditioner. These (2) contacts automatically come ready to use in the switch. If additional load management/shedding is required, we offer PMM modules as individual accessories. Up to 4 PMM modules can be used with each switch to monitor and shed additional large motor loads like your hot water heater, well pump, etc. When the generator starts up, these 6 non-priority loads will remain off for 5 minutes. After 5 minutes, these non-priority loads will stagger start based on priority to ensure the most efficient generator use. First AC contact 1 and PMM Priority 1, fifteen seconds later it will start AC2 and P2, then P3, then P4. This eliminates the huge surge of these large motors all at the same time, which allows a smaller generator to power more by running more efficiently. The load shedding module will monitor the generator while it is operating to ensure it is not overloaded. If the generator becomes overloaded, (if the engine frequency drops) the load shed module will shed all of the connected loads, reducing the demand on the generator. The load shed module will then begin a five minute timer, after which, each load will be brought on in priority order. Typically via a 15-second stagger start. Each time the generator becomes overloaded, the load shed module will intervene to prevent the unit from shutting down. To confirm whether or not your chosen generator has load shedding capabilities, or to verify which load management modules need to be used on your generator, we would recommend contacting Generac directly at 888-GENERAC (436-3722).