Generator - A/C issue

[Xmcdog]

Unfortunately gensets are sold by wattage.

Using a little ohms law will take you either way.

[A Frame]

Well the small ones are for sure. Did generators for about 15 years before I did my career change into pipelines. Here is a chart that will help

Originally Posted by Xmcdog

Unfortunately gensets are sold by wattage.

Using a little ohms law will take you either way.

[Band Of One]

Original poster here:
I really appreciate all the comments, especially the ones about Watts and Amp, but the issue I have must be unique as again the generator is working and does not default to overload when running in eco mode when the compressor comes on. It only defaults to overload when the generator is running at full throttle RPMs (about 3600) and the compressor comes on. When it is running in eco mode it is running at 2650 RPM's and then jumps to 3050 RPMs when compressor comes on and does not default to overload. The generator obviously has enough watts or is able to carry the amp load at 3050 RPMs. If that was happening in reverse it would make sense it did not have enough watts or was not able to boost up to compensate for the amp load when the compressor comes on but something else is going on. Could there be something wrong with the generator computer "over sensing" the load when it is in full throttle mode and defaulting to overload?

[NFlcamper]

Could be that there may be a timer, a capacitor, or other failsafe for eco mode. It allows the motor to get to the speed to produce the needed power. I would run it in eco mode anyway, I do mine. Saves you fuel as it allows the generator to slow down, and run cooler.

[followingsea]

Originally Posted by L.C.Gray

...At 7,500 ft elev the loss is about 22.5%. ..

Another thing to consider is dynamic response. My propane fueled 6500 watt Onan would not load the micro wave at 6000 ft the other days. When frequency dipped to 55 hz, protective circuit tripped off 120 vac but the generator kept running. After a short period, 120 vac would come bace.

Today I am at 2000 feet and the generator loaded both the micro wave and the a/c without issue.

[followingsea]

Originally Posted by A Frame

Well the small ones are for sure. Did generators for about 15 years before I did my career change into pipelines. Here is a chart that will helpAttachment 280143

Ohm's Law applies to DC circuits. AC generators have to also consider reactive and inductive loads which is taken into account by power factor.

You need both an engine with enough power to drive the generator and big enough wire to carry the current.

[A Frame]

Originally Posted by followingsea

Ohm's Law applies to DC circuits. AC generators have to also consider reactive and inductive loads which is taken into account by power factor.

You need both an engine with enough power to drive the generator and big enough wire to carry the current.

Very true, and is why I posted this. Everyone needs to at least buy 20% over to cover their AC load when starting. I have found my trailer only has one GFI that covers all the other outlets in my trailer which is wired for 15 amps total. Not much to work with when it comes to 4 outlets on the same circuit. I have not made sure the microwave is on it.

[followingsea]

Originally Posted by A Frame

.... I have not made sure the microwave is on it.

My microwave is not on the GFI but on the inverter as is the GFI circuit. Also the frig can be powered either off the battery or propane.

My electrical system does not like moist wind blowing off salt water. If it is not one thing it is another.

[Band Of One]

I'm in south Louisiana so altitude is not a consideration. The delay in eco mode verses a quick speed up in full throttle mode might be some of the problem however i think the generator was built with that in mind. Again, the generator in eco mode, speeds up to 3050 rpm from 2650 when compressor comes on but defaults when running at full throttle (3600 rps) as it tries to speed up when compressor come on. If it carries the compressor start up load and holds at 3050 rpms shouldn't it hold and run the A/C at 3600 rpms without going into default?

[KanzKran]

Originally Posted by followingsea

You need both an engine with enough power to drive the generator and big enough wire to carry the current.

This. It's why generators are spec'd in both kW (power) and kVA (magnetics and wiring), or at least industrial/standby/back-up gen sets are. Not small ones usually.