AC Hard start additions

Gdetrailer wrote:

TurnThePage wrote:
So... Are you saying that soft start devices harm or stress the A/C? Hard start caps also reduce that "thump" that happens at the moment the compressor fires up.

I totally agree that a properly sized generator should be used, but I've never heard from any reputable source that there is any harm in using hard start caps or soft start electronics.

If the gen voltage sags well enough before tripping a breaker or sending gen into overload, absolutely.

Softstart devices which "ramp up" voltage over time in an attempt to break loose the locked rotor are doing the very same thing that everyone on this forum crys foul over with sagging campground voltages by electronically reducing voltage going to the compressor then ramping it up (IE "soft start") over a short period of time.

There is no "free lunch"..

Additionally, the "add ons" may work OK in your driveway in 80F temps but add in elevation at your campsite and more heat and you have a good chance that it isn't going to work reliably or at all.

Why bother messing around with a undersized gen and hoping it will work fine.

For those scared of 50lbs more weight, get creative. You can buy a nice set of light weight aluminum fold up ramps and wheel it right on. You can get portable lift tables with wheels which are nice, a little creativity you can find quite a few ways to safely hoist or lift a 100 lb gen..

Heck for myself, I use my tractor front loader to lift and place my 100 lb 4Kw gen into my truck bed.. I also have used 10ft boards with cheap aluminum ramp ends to ease the gen on to the tailgate..

I do cheat a bit and leave the gen in the truck bed and run it when needed..

my experience with a Coleman Mach III 13.5K BTU AC non "high efficency", honda 2200, micro air easy start, at 7,000 ft altitude, outside temps near 100F. Density altitude near 8500ft.

AC starts smoothly and quickly with generator in eco mode, doesn't ramp up to full rpm. Had the converter off. Next, how much "spare" power could the honda 2200 supply at 7,000ft when outside temp was near 100F and AC running? changed the fridge to AC from propane adds about 300W. Genny still running not in overload. Voltage from the generator still at 122V. turned on the converter with the batteries near full charge, generator still running hours later still at 122 v

measuring generator output voltage during startup with a NIST traceable meter that will catch 10ms windows shows the lowest voltage during startup is 115V RMS, actually higher than some campground voltages!

Measuring running current with a calibrated clamp on meter shows I'm still below the continous current rating on the 2200 on AC only. So, given that I doubt I'm overstressing the generator.

Now a honda 2000 will overload at about 3,000Ft. The 2200 in addition to have 200more VA, has a 25% larger motor so in a sense honda has overcome the altitude derating of most generators.



BTW the micro air easy start has a "overload" sensor that is quicker and more stringent on overload than the honda. It will kick out the AC if it senses an overload instead of waiting for the generator to kick out, then after 10 minutes try a restart. As a test I turned on another 500W load to see what the micro air would do sense that would overload the generator. AC quit, honda dropped down in rpm to supply the other loads. turned off the 500W load, 10 minutes later AC came back on.

next tried the same thing but this time turning on the microwave. Same results, AC quite, generator kept the microwave running.

Conclusion: 1) My honda 2200 will run a coleman MachIII with easy start at 7000ft altitude continously without exceeding continous rating. 2) Micro air does an excellent job of detecting possible overloads and acting as a load shed device shedding the AC under overload.

How other 2000ish generators do, don't know. Some probably would work just fine, others likely are like the old honda 2000 at higher altitude.