That 10 amp startup reading has to be incorrect. A 15,000 btuh air conditioner draws more that that running steady, and a LOT more than that for startup. For the record, an eu2000i will start my RVP Coleman 15,000 btuh air conditioner. After the head pressure builds for a few minutes the power draw exceeds the eu2000i's continuous rating, so it's not a feasible combination.
I have a built in propane generator. It's great for running the microwave for a few minutes here or there, or a short stint with the air conditioner. Having a diesel rig, a built-in gasoline generator is not a practical option. A big advantage of the propane generator is to never have to worry about the carb being gummed up. For running the air conditioner a lot, or charging the battery while boondocking, it's not a good choice because it goes through the propane so quickly. When boondocking I carry an eu2000i to charge the battery, and don't go where I'll need much of the air conditioner.
Unverified opinion: If the Ryobi's output voltage and frequency are within the Honda specs the eu2000i should sync up with it. There shouldn't be any risk of damage (remember: opinion). The major problem I see that applies trying to sync a Honda inverter generator with any other is that Honda seems to stand alone with an output voltage at or near 128. This would mean that the two generators wouldn't share the load very gracefully, with the Honda carrying all of the load until it's close to being maxed out and its voltage gets pulled down. The subject Ryobi is the only currently available non-Honda/Yamaha generator I know of that parallels without the used of a sync line in its parallel cable. When Kipor did this years ago, Honda jumped all over them and the product got withdrawn from the market. Makes me wonder if Ryobi is licensing the technology from Honda and/or Yamaha, or if they're about to feel the wrath of Honda's lawyers?
The best and easiest way is to use a "memo-scope" and a current probe.I agree but what do you do with the data? Peak, average, RMS, single cycle, over a time window, how long is the window, etc? Even if there's a standard I don't know about, does the generator conform to that standard? I think this is a case where the only practical measurement is to try it and see if it works, or get enough user reports to have a fairly high level of confidence of the expected result. From what I've read, the Yamaha 2400 has a pretty good success rate with 13,500 btuh air conditioners, but there are some exceptions.
Even if somebody has real numbers I don't think you can put a lot of faith in them. AFIAK there's no standard definition for a surge measurement. When a motor starts, the first AC cycle generally draws the most current and it tapers down from there over a second or two. Does a surge measuring meter capture the peak at an individual cycle level? Does it sample over a certain time window and report the average? Is it reporting peak, average, or RMS values? I don't think there's much if any standardization between meters. Just as trivia I've measured the eu2000i peaking out at around 43 amps which it can sustain for only a couple of AC cycles.
At a typical 80% efficiency and 0.7 power factor, a maxed-out 60 amp converter will draw over 1,500 VA, and a maxed-out 75 amp converter over 1,900 VA. You can get away with higher than 60 amps on an eu2000i if you're willing to make sure the battery doesn't get highly discharged, cut other loads when necessary, and/or manually kick the converter out of boost mode when necessary. If you really need the bigger converter, a power factor corrected model might be justified.
I have a different rig, so this may or may not apply, but your story sounds awfully familiar. In mine, there's a 150 amp fuse in the battery interconnect circuit. This is what happens:
1. Chassis battery is dead.
2. Connect to shore power or generator, coach battery gets charged from converter.
3. Battery interconnect engages.
4. Dead chassis battery pulls more than 150 amps from the coach battery/converter combination.
5. 150 amp fuse blows.
This has happened more than once with rigs similar to mine.
I believe the stated information is:
1. No continuity neutral-to-ground in the unplugged RV. This is correct.
2. Dead short neutral-to-ground in the shore power outlet. This is correct.
3. ~30 volts AC from the chassis ground to the ground terminal of an AC outlet. This is incorrect and a significant safety hazard. It means the safety ground from the shore power outlet is not connected to the RV chassis as it should be.
The Progressive Dynamics converters are pretty bad with RFI emissions. Your situation sounds worse than what I have observed. Fixing the ground connection (item 3 above) might help with this.
I'm going to speculate that the 240 volt model is just straight 240, not split phase, because providing split phase would run the cost up considerably. Unless of course 2 of them are stacked to get the 240 volts. If the price was reasonable that would be a handy capability.
Have to love the "creativity" of the Marketing folks. The first listed feature on the web page is "Constant Speed Operation for long life", which I think is just opposite of reality. I think they'd be better off pointing out the 2,200 RPM engine speed. Looks like it's liquid cooled, making it kind of a baby high-end unit. I wonder how many people will follow the directions to check the oil and coolant level every day, then performing a visual inspection before applying a load? I'm also wondering about the power specs: 5 HP engine and 3,000 watt output, that makes the generator head 80.4% efficient. Are they really that good these days?
Even with good inverter efficiency data I think there's more to the story. If the load runs hotter with MSW, some of its increased efficiency is thrown away further down the line. To get a real data you probably have to measure different inverters with your own loads. What matters is how much power is pulled from the battery to get the job done.
Without good electrical measurements or swapping components everything is opinion. Mine is that there's something wrong with your generator, air conditioner, the interconnections, or you have an additional AC load you aren't aware of. I base my opinion on (1) My eu2000i started a 57915 with 100% reliability on 90+ days, and (2) It will start my current 15,000 btuh unit at at 70+ degrees and 3,500 feet, (3) Compared to the eu2000i, the 2400 VA Yamaha is "over engined", so I'd expect it to do better than a straight 20% improvement over the eu2000i.
The surge protector is not able to make an absolute measurement about the integrity of any of the wires. It has 3 sources of information: The voltages of the 3 wires carried on the power cord. When the relationships aren't right, it uses some sort of algorithm to proclaim what the specific fault is. The algorithm is probably correct most of the time, but there will be low-probability situations where it gives the wrong diagnosis. Since you're getting power in the rig, either the neutral is ok, or it's really bad and the RV is also miswired. Pending further data, I'd also suspect a problem with the safety ground at the pedestal.
In the rig where I had the Brisk Air unit, a 2003 Cougar 5th wheel, it did start the compressor first followed by the blower about 5 seconds later. It was a standard DuoTherm thermostat, not digital, not for a heat pump. Surely I'm not the only one where it worked this way, yet I've never seen a post about it from anybody else.
The good news is that, based my my experience and others who have made posts, you've got one of the more generator-friendly air conditioners. Several of us have measured the Brisk Air units as drawing less power than what the published specs say. And to be balanced, at least one very experienced RV tech is of the opinion that this indicates something is wrong with the air conditioners. In my case, on a mid-90s day at 500' elevation, the 57915 Brisk Air pulled 1,320 watts and 11.5 amps at 120 volts with the fan on high. (Watts are lower than volts*amps because of the power factor). I do not know the tail end of the 57915 model number.
You might get by with less than a 3,000 VA generator. Many have, but as you go lower the risk of an undesirable outcome increases. A 3,000 watt inverter generator should be safe (no guarantees, however). You're probably good with a 2,400 VA Yamaha inverter generator but there will be times when you can get tripped up if the battery is charging heavily, you forget to switch the fridge to propane, it's over 100*, and/or you're at a high altitude. A 2,000 VA Honda or Yamaha inverter generator has worked for a lot of Brisk Air users, but you definitely have to actively manage the other AC loads and keep the altitude under a couple thousand feet. It boils down to the tradeoff you want to make between generator size and weight, cost, and ease of use. Even with all the information you can gather, there's absolutely no substitute for actually trying the generator you're interested in with your rig under actual conditions.
It's hit-and-miss depending on your air conditioner and how well you manage the other AC loads. Many (not all) of the 13,500 btuh air conditioners draw below 1,400 VA running on a hot day. If you keep the other AC loads down and the generator can start the air conditioner, there's no problem running it indefinitely. If you leave the fridge on electric or have a heavily discharged battery, there's no chance of it working. The generator's capability goes down as the temperature and/or altitude go up. I use my eu2000i at 3,500 ft, and on a 90+ degree day it cannot sustain its 1,600 VA continuous rating. On the other hand, when I ran the 13.5 btuh air conditioner at the coast, the eu2000i didn't even rev to its full RPMs.