Automated Generator Break-In

I purchased a new Champion generator for home backup use, and wanted to give it a good break-in per the manufacturer's recommendations. The manual says this about the break-in:

The first 5 hours of run time are the break-in period for the unit. During the break-in period stay at or below 50% of the running watt rating and vary the load occasionally to allow stator windings to heat and cool. Adjusting the load will also cause engine speed to vary slightly and help seat piston rings. After the 5 hour break-in period, change the oil.

To be honest, this is a little vague and would be so time consuming that I doubt that it's usually done well. I decided to attack the problem with a Smart Plug, an old electric space heater, and my Home Assistant instance. A Home Assistant automation can turn the smart plug/heater on and off periodically to vary the load.

The Smart Plug I used was a TP-Link HS103. This is a relay-based plug rated at 15 Amps. The space heater was an old 1500 Watt unit that draws 12.5 Amps. The space heater provides a nice (mostly resistive) load for the plug and is well within the 50% load recommendation.

It would be possible, though tedious, to do the break-in without Home Assistant by entering a schedule in the TP-Link app. Still, this would be less effort than attending your generator for 5 hours.

In Home Assistant, I created a new Automation to do the job. I selected Settings, then Automations and Scenes, then Create New Automation. Select Add Trigger, Time and Location, then Time Pattern, then place /x in the minutes field. This will trigger the Automation every x minutes. I chose to vary the load every 5 minutes. (I called Champion tech support, but they were unable to give me an optimum interval to vary the load). Then choose Add Action, Device, select your smart plug, then under Action, choose Toggle. My Automation Screen appears below.

Test the automation by plugging in the Smart Plug and verifying that it periodically changes states as programmed.

When performing the break-in, plug the Smart Plug and heater into the running generator (i.e. do not attempt to start the generator under load). I did the break-in over several sessions, heeding the manufacturer's notice to check the oil level often.

When break-in was completed, I deleted the HA automation. The Smart Plug is now available for other uses.