Automatic Generator Start for Onan 5500 Generator


Well-known member
Just want to share some thoughts on the fairly new automatic generator start system from Cummins for Onan generators.

I recently purchased the EC-AGS+ (automatic generator start) system from Cummins and installed it on our Cyclone 4005's Onan 5500 generator. The install was pretty simple, and I can now access the generator settings with my smartphone and can even start the generator from my phone. We were mostly interested in having the generator start automatically if we are away from our RV and the campground power goes out, especially if the dogs are in the rig. In that regard, I found the system has one big shortcoming. If the shore power goes out, the AGS won't engage the auto-start until the batteries drop below 12.5 volts. When I tested the system, I cut AC power to the Cyclone and our batteries were still putting out about 12.7 volts, so no auto-start. After waiting over an hour, the batteries had still not run down enough to engage the auto-start. And unfortunately, the software app won't allow me to set the voltage to engage auto-start any higher than 12.5 volts. If I could just set the trigger to 13.0 volts, it would immediately detect a loss of shore power and the generator would start after about 30 seconds. I've tried to contact Cummins about this, as it seems a simple change to their software would solve the problem by letting me set the voltage higher. But so far, no response from Cummins (and I have tried twice). There is also an option in the software to engage the auto-start when the indoor air temperature rises to a certain point (they provide a temperature sensor), but I really don't want the rig to heat up that high before the generator kicks in. This AGS is a great idea with a couple glaring drawbacks in the design. The other drawback is the system utilizes a bluetooth connection rather than wifi, so you can only access the generator with your smartphone if you're within about 30 feet of the rig. If it would use a wifi connection, the hotspot in our rig would allow me to access the generator settings from anywhere.