I use the 30 amp hard wired Progressive Industries unit. Note that if you plan on using a standalone generator, you will need to make up a ground-neutral bonding plug or else the EMS will detect a floating ground and you’ll get an error code. The plug is easy to make or buy.

I have the hard wire progressive industries 50 amp works great. As Richard said if you use stand alone generator you need to make a ground neutral bonding plug or you have to turn off the progressive industries.would buy again

We use the PD 30 amp pigtail plug. We rarely plug in and don’t use a generator but the product has worked well and the quality seems great. Nice piece of mind. A lot easiest than troubleshooting the campground circuit with a multimeter before plugging in.

I use this Technology Research Surge Guard 34830 Portable Model with LCD Display - 30 Amp. We do mainly full hookup camping and it has worked well for over 2 years. When I was looking for one I made sure it had high and low voltage protection. It also has a delay and I restart one conditions return to a safe operating range.
Good luck with you purchase!

We use a 30amp progressive and love it overall. The only thing I would mention is that when connected to 15 20 amp service maybe in you driveway parked at home or driveway surfing it may cycle on/off due to voltage drop. My battery charger equalizes when first started for short period as I believe most do. System is working as designed to protect from low voltage. On 30 amp service we never have any issues. And our generator has a 30 amp connection so no adapter needed. Progressive has lifetime warranty I believe and would say that’s the way to go.

I've had the PI EMS 30 amp hard wired since 2012, has worked well. I did kill it once playing around with my AC trying to run it off just one of my 2000w Champions. They sent me out a new control board for free under the lifetime warranty, just had to pay to ship the old board back.

There is a disclaimer on their website about Yamaha generators voiding the warranty - https://www.progressiveindustries.net/disclaimer

I think what happens is some generator inverter circuits under heavy, heavy load will produce a jagged wave instead of a pure sine wave and causes a component to fail on the PI control board. On mine, it was an open 47-ohm resistor.

I bought the Progressive 50 amp and hardwire ours myself. They have a very good customer service. Ours was defective and luckily they are close to us and I had it the next day. Make sure you put the card that has fault codes on it in a good place to find. It comes with the unit. Oh we have two Honda 2000 inverter and companion and I had to make a special plug account the progressive tripped showing a fault. Under the progressive website it talks about this issue. They sell it but I had an old drop cord and made one myself. It plugs into the inverter receptacle.

I made the neutral-ground bonding plug. Just take any plug and connect the neutral and ground prongs together. I did it inside of a plug housing and just leave it plugged into one of the generator outlets all the time.

So I have a question about the use of a generator and the progressive 50 amp surge protector. I am planning to purchase a Champion duel fuel and already have a progressive 50 amp portable system eventually I hope to have 2 generators in parallel. So will I need this neutral grounding plug for the surge system to work correctly?

Here is a good link to check out on the subject - http://noshockzone.org/generator-ground-neutral-bonding/ Lots of info in the comment thread too.

I installed a Progressive Industries set up on my coach and it would not let my Honda 2000 work it’s magic. Contacted Progressive and they told me I needed to buy a bypass switch that hard wires into their box. The solution that the above link provides is cheaper and a lot easier to install. Go with Mike Sokols suggestion.

I have the hard wire progressive industries 30 amp works great. Really like the display of Voltage, Hertz and Amperage being used. would buy again

Thanks for the info. I made one like yours. fired up my inverter / generator plugged in the tester and it showed an open ground error, put the N-G Bond plug in the other outlet, no ground fault.