If you are considering the PUH line of inverters with the internal automatic transfer switch, don't trust the manual or marketing materials concerning the operation of the ATS. The inverter must be turned on at all times to output 120V power, even when on shore power. The result is that even in sub-freezing temperatures, the cooling fans in my installation operate for 60 seconds every 30 minutes like clockwork. If you install the inverter in a travel trailer pass through like I did, that means that the two powerful fans may be running right below your pillow on a very regular schedule. The only thing that operates on 120V at night in my TT is an absorption refrigerator drawing only about 300 watts. Renogy in no way revealed this fatal flaw until I contacted tech support. Renogy did offer a 5% refund in partial compensation, but such an offer does not come close to the costs for parts and labor and the inconvenience of a need to now install an external transfer switch.

Language in the owner’s manual specifically contradicts the reality that the inverter must be powered on at all times to output 120V power. On page 16, the manual states “Utilizing the built-in transfer switch, this inverter seamlessly switches to grid power bypassing the inverter when it’s available, thereby directly supplying the load with grid power”. I would argue that if the inverter must be turned on and that the technicians claim (see below) it is boosting power to maintain a stable power supply when on shore power, then there is nothing bypassed or directly supplied about it.

I cannot imagine why the Renogy believes that their inverter in necessary to maintain a stable power supply when on shore power. That is a service the electric company provides in exchange for my money. The following is copied from my email correspondence with tech support:

Dear Customer,

Thank you for your detailed feedback regarding the inverter's cooling fan operation and the remote control requirement while on shore power. We sincerely apologize for the significant inconvenience and sleep disruption this has caused you.

We understand your concerns and hope the following technical explanation helps clarify the situation:

Fan Operation in Bypass Mode: Even when the inverter is in bypass mode (passing through shore power), its internal boost circuitry operates intermittently. This is necessary to maintain a stable power supply. This operation can cause the transformer temperature to rise. If the temperature exceeds a certain threshold, the fans will activate automatically as a critical safety feature to prevent overheating and potential component damage. Therefore, this behavior is a normal and necessary function to ensure the inverter's long-term reliability, though we understand it is disruptive in your quiet camping environment.

Remote Control Requirement & Sleep Disruption: We understand that the brightly lit remote control is also a disturbance. As a practical workaround for better sleep, we recommend installing the remote switch in a location farther from your sleeping area. This would allow you to control the inverter's on/off state conveniently from your bedside when needed, while keeping the bright LED light at a comfortable distance during rest.

While we are unable to address these specific operational characteristics through a simple software update at this time, we deeply value your feedback and the frustration it has caused.it has caused.

Solid built, features I didn't expect for the price.
A well built unit that makes me anticipate years of great service.
So happy I went with Renogy!

I'll be back..

It’s certainly a pretty thing. I have yet to put it thru its paces, but it does work as expected. This is an upgrade for a perfectly working 2000watt Renogy inverter. I won’t be using the transfer switch function, but I really like the heavy load output wiring hookup.

Setup was a breeze. It’s really plug and play.

I am very happy with the Inverter. Build is solid and well constructed.
My only complaint against the transfer switch, is it would be nice if there was a way to get it to transfer 110vac shore power without the need to have the unit in the "on" state which also requires it be connected to a charged 12V battery.