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Joel
08-26-2011, 09:43 PM
I just purchased a little 800 watt, 2-stroke generator:

http://img.photobucket.com/albums/v186/JoelinTX/HFGen.jpg


http://www.harborfreight.com/800-rated-watts-900-max-watts-portable-generator-66619.html


The frequency holds well at 59-60hz, both loaded and unloaded, and I believe the freq can easily be altered by adjusting the rpm. The problem is that I am getting about 112 volt unloaded and 107 loaded.

Is there anything I can reasonably do to improve this?
I won’t be running any electronic devices from this generator, but how close does the voltage have to be before I will start causing problems with, say, a refrigerator?

I have run it for a couple of hours with a halogen light for a load and it is quiet and seems to run quite well. Curiously, they recommend a 25 hour break-in at 50% load, which seems more likely closer to the ‘breaking’ period.

Black_Moons
08-26-2011, 10:14 PM
Unless your fridge is a mini bar fridge, It won't run on that generator. the startup inrush will likey kill the generator.

Same with any sizable motor load really.

100v even should'nt really damage anything to be honest, might just underproform a little bit.

Easyest way to change its voltage... Return it for a new one? :P

Or buy an "AVR" automatic voltage regulator.. they have a multitap transformer to boost/buck voltage, and relays to alter the taps used as needed.

macona
08-26-2011, 10:23 PM
Most everything is rated at least +/-10%. And anything electronic is almost always 100v-240v input.

tdmidget
08-26-2011, 10:59 PM
It just needs a 9/64 exhaust and it's ready to go.

dp
08-26-2011, 11:11 PM
The voltage at your normal wall socket will move around as much as your generator. Even more now that the EPA is forcing the shutdown of diesel generators. It's a good time to buy a "Brown Out Special" home generator. I'm looking for a natural gas version.

Willy
08-26-2011, 11:59 PM
The voltage is not going to be an issue.

But as BM already said...you will never be able to start a regular house sized fridge with that generator.

Starting wattage on reactive loads like a fridge typically run up to 3 times of what it uses while running.

dp
08-27-2011, 12:10 AM
Here's what a quick google search turned up for starting loads:

http://www.generatorjoe.net/html/startingload.html

Using this for a typical reefer:
Refrigerator (frost-free, 16 cubic feet) = 725W

You probably won't get there. But - you can get a 1500kw APC that you can keep charged from your genny and which will handle the starting load of the reefer. Once the reefer is running the APC cuts off and you run on the genny.

I buy used APC (tm) battery backups in the 1.5kw range for $5 - $15 at a local PC recycling shop and buy replacement batteries at Fries Electronics for a song.

macona
08-27-2011, 12:35 AM
The voltage at your normal wall socket will move around as much as your generator. Even more now that the EPA is forcing the shutdown of diesel generators. It's a good time to buy a "Brown Out Special" home generator. I'm looking for a natural gas version.

EPA is doing what? I know the listeroids are nat allowed in the country, but if you ever saw one running first hand you would see why.

dp
08-27-2011, 12:55 AM
Don't consider this to be the word down from God - take it as a trail head and follow the idea on Google to as many sites as you need to get the drift:

http://www.thenewamerican.com/tech-mainmenu-30/environment/8700-epa-regulations-to-shut-down-coal-plants-and-raise-energy-prices

CO2 is now a poison, according to the EPA, to be regulated like bovine farts and dichlorodifluoromethane. The linked site has enough keywords to keep you busy until your head explodes.

lakeside53
08-27-2011, 02:53 AM
And.... how are you measuring? The waveform from the small generators is anything but a sine wave. Unless your meter is reading true rms, it may be way off.

The Artful Bodger
08-27-2011, 03:31 AM
And.... how are you measuring? The waveform from the small generators is anything but a sine wave. Unless your meter is reading true rms, it may be way off.


Who says the outputs are not sine waves? Where did this snippet come from/

macona
08-27-2011, 03:50 AM
Hmm, I think that site might just be a touch biased. As much as I dislike the federal government getting into our lives their notion of just eliminating the EPA is nuts. EPA has been a double sided sword, business and industry has shown over and over that left to their own devices they will do no more than they have to limit and control their pollution. On the other hand EPA has grown more and more power hungry, this whole carbon scheme has got to go.

lakeside, they are sine-ish. No where as clean as utility. That can be enough to throw off cheap multimeters.

The Artful Bodger
08-27-2011, 03:58 AM
I was under the impression that even simple alternators produce a good sine way and in fact it is not easy to build an alternator that produces anything else!

Utility mains are not perfectly clean as they have to contend with all manner of switching spikes and goodness knows what else.


Whatever the problems might be with small alternators I would be suprised if wave form is a major issue.:rolleyes:

Joel
08-27-2011, 04:33 AM
I take it that the output voltage is not something I can easily change then. I suspect with a full load the voltage will drop further.

So, no worries at this point, but at what level should I be concerned about possible damage or reduced lifespan of the load?
And yes, am using a true RMS VOM. I absentmindedly grabbed the cheap VOM I keep laying around the shop first, which failed to give a meaningful reading.

I should have added this to my original questions:
What would be the simplest way to add a 12v outlet?


Thanks a bunch for the help guys.

flylo
08-27-2011, 09:09 AM
Adding a 12V outlet. I've bought 2 things off Ebay for $1.70/Delv each that plug in the wall & have a lighter style power port. They work great.

J Tiers
08-27-2011, 09:25 AM
1) NO. Generators do NOT have to give a good sine wave. It is pretty common for them to give a wave with a flattish top under load, somewhat trapezoidal. Particularly cheap ones. It depends on the load type also. Some loads "clip" the wave, and a low-power generator may not be able to hold up voltage.

2) If a true RMS meter gives a very different reading from a standard average-reading type, it is PROOF POSITIVE that you do not have a sine wave...... They are calibrated to read identically on a sine, but differ widely when there are harmonics, as with any non-sine signal. (minor amounts of difference due to calibration doesn't count)

3) as for changing the output, it depends on the way the generator is made..... Those are cheaply made, I don't know if they are PM or wired field, nor how the excitation works if wired.
A generator will put out more voltage if the field is stronger. but you may or may not be able to control that.

lakeside53
08-27-2011, 10:50 AM
I was under the impression that even simple alternators produce a good sine way and in fact it is not easy to build an alternator that produces anything else! Utility mains are not perfectly clean as they have to contend with all manner of switching spikes and goodness knows what else.

Whatever the problems might be with small alternators I would be suprised if wave form is a major issue.


Yes, they supposedly put out a sine wave, but it's lousy at best. I've put a distortion analyzer and scope on many consumer grade generators. You can see over 35% harmonic distortion. The best I've seen was about 8% (that's "ok") but it was about 3X price. As a comparision, utility is usually about 2-3% (but your mileage may vary).

My current typical consumer 10kw (highly optmistic number) generator under no load has a very flat top, steep sides with ragged overshoot and a "narrow" waveform. Under a 5kw resistive load, it's not a lot better. Horrible with light dimmers -they tend to go from off to on suddenly (steep sided waveform), my microwave works at maybe 60% (takes much longer to boil water), and my fan motors whine. And.. my UPS keeps telling me I have "power quality" problems. lol... I keep thinking I'll find a compatible quality head from say Gillette, but none ever seem to come my way.

GKman
08-27-2011, 12:11 PM
It just needs a 9/64 exhaust and it's ready to go.

HUH? .

bborr01
08-27-2011, 12:14 PM
It just needs a 9/64 exhaust and it's ready to go.

Exactly the same thought I had when I started reading this thread.

Brian

dockrat
08-27-2011, 12:49 PM
It just needs a 9/64 exhaust and it's ready to go.

lol tgmidget too funny!!!!!!!:D

bborr01 and GKman it refers to this thread

http://bbs.homeshopmachinist.net/showthread.php?t=34767&highlight=airsmith+exhaust

Abner
08-27-2011, 04:20 PM
DO NOT QUOTE ME.
I have heard that frequency is more important that voltage (with in reason). I find appliances run better when I get the frequency close to 60 hz +/- 2hz. Voltage can vary from 115-125.
You will need a good meter. I use a fluke.

tdmidget
08-27-2011, 06:50 PM
Don't consider this to be the word down from God - take it as a trail head and follow the idea on Google to as many sites as you need to get the drift:

http://www.thenewamerican.com/tech-mainmenu-30/environment/8700-epa-regulations-to-shut-down-coal-plants-and-raise-energy-prices

CO2 is now a poison, according to the EPA, to be regulated like bovine farts and dichlorodifluoromethane. The linked site has enough keywords to keep you busy until your head explodes.

I didn't see the word diesel in that article

Joel
08-31-2011, 09:27 PM
An FYI for anyone interested - this little generator started and ran my full sized refrigerator. Everything sounded ok, but the voltage dropped to 105v. :eek:
Hope that's not going to be hard on the compressor. the frequency stayed good at 59Hz.

darryl
08-31-2011, 10:15 PM
Started and ran your full size fridge- great. You're probably ok if the startup to normal running takes place in about the same amount of time that it normally takes being plugged into the grid.

Something that might be worth looking into is some kind of unloader relay that would work by operating when a heavy load like a motor starting comes on. The relay would have normally closed contacts, and a heavy draw from a dedicated output would open the contacts. Anything powered through those contacts would shut off momentarily as the motor got up to speed. You'd probably have lights, maybe a radio- it wouldn't matter if those got interrupted. This could make the difference if your generator didn't have a lot of headroom to power the load you might have on it. It could help you get by with a smaller generator in a situation where most of the time it's relatively lightly loaded. Burn less fuel most of the time too-

bewards
09-01-2011, 10:01 AM
And.... how are you measuring? The waveform from the small generators is anything but a sine wave. Unless your meter is reading true rms, it may be way off.

I had this problem checking out an old UPS. The meter I was using was a new digital auto ranging one. It kept showing the wrong voltages when on battery power. I had to round up a analog one that was my dads and is probably 50 years old to get the right reading. The output wave form was fooling my digital meter.

upon edit, posted before reading the whole thread
be

troyken
09-01-2011, 01:50 PM
I bought one of these for my father for fathers day last June. He used it for 3-4 days this week in the aftermath of the hurricane /tropical storm. He ran an 18 cuft fridge/freezer with it from a 14awg extension cord. Started fine and the generator sounded great. His observation was that the generator ran cleaner ( less odor) on premix 40:1 two stroke fuel ( Sears, Walmart ect in quart cans), than it did on fresh 87octane regular gas(10% ethanol) with Homelite synthetic two stroke oil at 50:1. He said it was quite fuel efficient and he ran it off and on about 5 hrs/day. I heard it and the noise was far less than my 2250 watt 5hp Coleman generator (4 stroke).

I did see on youtube the recommendation to change the original spark plug to a Bosch plug. We may do that. All in all it was well worth the $89.00, lightweight, easy starting , and powerfull enough for essential loads. That two stroke premix fuel has a long shelf life and our local Fire House buys it in 55 gal drums for saws, generators, hurst tool and the like. Expensive but worth it for emergency use.

On edit I forgot to mention that the length/ AWG of extension cord makes all the difference, but then we all knew that right?

Paul Alciatore
09-02-2011, 08:29 PM
I had this problem checking out an old UPS. The meter I was using was a new digital auto ranging one. It kept showing the wrong voltages when on battery power. I had to round up a analog one that was my dads and is probably 50 years old to get the right reading. The output wave form was fooling my digital meter.

upon edit, posted before reading the whole thread
be

Inexpensive digital meters, and that includes about 99% of those sold, and even some expensive ones are actualluy reading the peak Voltage and dividing it down by a factor based on the assumption that the waveform is a sine wave to arrive at the reading that is displayed. Only meters that are designed to read true RMS Voltage will give proper readings (the readings you want in the real world). Many analog meters do the same thing, but they will do a partial job of ignoring any high frequency spikes and SOME other distortions in the waveform. So they MAY give better readings even though they are not specifically designed as true RMS meters.

In general, only a meter that is actually designed as a true RMS meter will give accurate readings. And even then, you should read and understand the specs. because all meters have other factors that can change the readings. One such factor is the frequency response of the meter's circuitry. A low frequency response can cause even a good meter to ignore the high frequency components of a waveform and give a false reading.

I am glad the generator did work on your refrigerator. It will probably be OK for occasional use, such as power outages, but I would not recommend using it 24/7/365, for multiple years. Of course, under those conditions, the generator will need to be replaced far sooner than the refrig. FAR sooner!

Fred P
09-03-2011, 02:16 AM
I do not know about the generator in question but many of the small generators now days are not generators, but are 12v alternators with a built in inverter to up the out put to 120v +- AC. With this kind of a set up the speed of the engine has very little to do with the out put voltage or frequency.

Fred P.

J Tiers
09-03-2011, 09:28 AM
Paul is being a "little" extreme....... "true rms or the trash heap"......

95% of the time, it makes no difference which type meter you use. Even many Fluke meters are not true rms reading, they are "average reading, rms corrected".

Sometimes it does matter. And, a true rms meter can even give you a wrong reading, when an averaging meter gives you what you want. Knowing that difference is important to getting good results in the 5% of cases that it does matter.

tdmidget
09-03-2011, 10:14 AM
I do not know about the generator in question but many of the small generators now days are not generators, but are 12v alternators with a built in inverter to up the out put to 120v +- AC. With this kind of a set up the speed of the engine has very little to do with the out put voltage or frequency.

Fred P.
What in the world does that mean? A generator is not a generator?
Are you trying to say that it is an automotive alternator? Why would an alternator need a "built in inverter"? Alternators produce alternating current.

lakeside53
09-03-2011, 10:21 AM
A car alternator is a three phase generator, but low voltage. It would need an inverter to take it from 12v dc to 120v ac 60hz. If it's a cheap inverter, you get a "modified sine wave" (stepped square wave); better inverters swich at high frequencies and when filtered can put out a decent sine wave.

Fred P
09-03-2011, 12:50 PM
Many of the newer (generators) are not generators as we new them in the past, but are alternators that make first 12v ac then converted to 12v DC then fed in to a inverter to make the 120 v ac out put. If the generator also has 12v DC out put. it is most likely an alternator with a built in inverter to give the 120 v AC out put. Many of the smaller Hondas are built this way. The speed of the engine has less to do with the out put. Sometimes all those little electric things in the box are not working the way that we think that they should work. I just added this input so that you can look at your problem in another way. I will not tell you how long I worked on one before I came up with the above.

etpm
09-07-2011, 03:35 PM
An FYI for anyone interested - this little generator started and ran my full sized refrigerator. Everything sounded ok, but the voltage dropped to 105v. :eek:
Hope that's not going to be hard on the compressor. the frequency stayed good at 59Hz.
Greetings Joel,
I have an 850 watt two stroke industrial duty generator that's gotta be at least 20 years old. It too experiences a voltage drop when loaded to near its max. This may be OK. Voltage drop with induction motors is dangerous because the induction motor will try to draw more current in order to speed up. The higher current causes heating. So does the lower speed of the motor because the power consumed is not being output by the slower spinning motor shaft as efficiently. If the low voltage power supply can supply enough current, like what can happen during a brownout, then induction motors can overheat. Your 800 watt generator is probably not going to be able to supply enough current to overheat your fridge motor as long as the fridge starts every time. My little generator would start my fridge or freezer about 95% of the time. But every now and then it wouldn't. Then both the starting and running windings of the fridge motor would be energized and the starting winding overheats quickly, sometimes in less than 1 minute. So unless your generator never fails to start your fridge I wouldn't run it unless you are awake and can hear the starting failure. Or if your generator automatically pops a breaker when overloaded for less than 20 seconds or so. My little generator does and has an automatic breaker that disconnects the generator until the load is removed and then resets itself. Maybe yours does too.
Eric

Black_Moons
09-07-2011, 03:50 PM
Many of the newer (generators) are not generators as we new them in the past, but are alternators that make first 12v ac then converted to 12v DC then fed in to a inverter to make the 120 v ac out put. If the generator also has 12v DC out put. it is most likely an alternator with a built in inverter to give the 120 v AC out put. Many of the smaller Hondas are built this way. The speed of the engine has less to do with the out put. Sometimes all those little electric things in the box are not working the way that we think that they should work. I just added this input so that you can look at your problem in another way. I will not tell you how long I worked on one before I came up with the above.

These are very clearly marked "INVERTER GENERATORS" and typicaly cost like $700 for a 1000W one, and like $1000 for a 2000W one (Basic residential model)
Conversely, you can get a 6000W conventional generator for about $600~1000 here (depending on quality/make/model/electric start/etc)

The big advantage in inverter generators is they are not required to run at 3600rpm (or some fraction there of), Hence if you are just running a few light bulbs/etc, they can idle down. I made one myself outta a lawnmower, alternator and true sine inverter, worked very well, dispite the lawnmower being a POS that had the rpm surge up and down under load, with a bent shaft that leaks oil (tossed out the motor ages ago), and just had manual throttle control (+ the feedback govoner that lawnmowers have, so you basicly set RPM via the throttle, and just cranked RPM up higher before starting any heavy loads)

Bob D.
09-08-2011, 10:33 AM
The OP shows a pic of the HF #66619 genny that I'm considering picking up to run the circulating pump on my gas fired hot water baseboard heating system in the event of a power outage. I've read through all the 140 reviews on the HF site and it seems like a good unit if you check for minor assembly issues, (especially the fuel line) and install a name brand spark plug and use hi octane gas. And with the current coupon, it's US$89.99.

Any other experience with it here? I trust you guys! You always seem to know what you're talking about ( when things are on topic):)

PS: not to seem sexist using the word "guys" but I don't ever remember seeing a post by a female here....:cool:

darryl
09-08-2011, 10:46 PM
There's generators and there's alternators. Both generate electricity, but while an alternator is a generator, a generator is not an alternator. Hope that clears everything up :)

Before alternators came into use in vehicles, they had generators. Those had brushes, a rotor with a commutator, and a field winding. There was also a regulator, separate from the generator. The engine spun the rotor, the regulator fed current to the field, the resulting magnetic field made current flow in the rotor windings. That current was drawn off through the commutator and brushes. The output was DC. In an alternator, brushes feed field current to the rotor through slip rings, and there is no commutator. The rotor gets magnetized with four or more north poles, and an equal number of south poles. The magnetic field developed sweeps around all the laminated poles, causing current to flow in the windings. Each of three sets of windings delivers both positive and negative pulses of current as the polarity of the magnetic field passing the stator poles changes. The rectifiers turn both polarities of voltage into positive pulses, and the positive pulses are delivered sequentially by the three windings. The output is again DC- not pure DC, but an assemblage of positive waveforms. To a battery it's DC- current flowing in one direction to replace the charge that's been drawn out.

The faster the magnetic poles can pass a stator pole, the higher the induced voltage will be. The wire can be heavy gauge to keep losses low because the turns count can be low, and high currents can flow as long as sufficient mechanical power is applied to maintain high rotor rpm. This is one way an alternator shines- to a point, the faster it turns the more power it generates. When you hear alternator whine, that's a relatively high frequency, far higher than 60 hz. In the stationary 'generator', the alternator is comparatively larger than the equivalent in a vehicle, because it's restricted to developing 60 hz. Unless it's designed to output 3 phase, it will have only a single output winding. Maybe a pair of windings in parallel or in series, but it's single phase- whatever the winding count or connection is, it operates as a single winding. Much more iron is needed to output power at 60 hz than would be needed at say 400 hz ( a common frequency in airborne equipment) or at 1000 hz, which is not uncommonly generated in a vehicle alternator.

The alternator windings are stationary, so they don't need brushes to pick the current off. The generator windings are rotating, so they do need brushes to pick the current off. A happy coincidence is that the brushes and commutator do a sort of mechanical switching so the high current rectifiers aren't needed. The generator doesn't need brushes to feed field current- the alternator does. Happily, the field current is much lower than the output current, so the brushes don't have to deal with the total output current, plus they don't have comm segments wiping under them. It's an easy job for a brush since it's low current and it doesn't do any switching.

The alternator wins out as we all know. You can't buy a vehicle anymore that uses a generator, they all use alternators.

Same for these things called 'generators', or standby generators, or home generators, backup generators, or gennies. All have alternators. If a particular unit also has an inverter, it most likely means it's using something more like an automotive alternator, and the inverter is absolutely needed if you are to be able to get 60 hz output. So- it can be smaller and lighter for the same power output, but it also gives the advantage of constant 60 hz output while the input rpm varies all over the place.

You can generate with an alternator, but you can't alternate with a generator- unless you 'alternate' the field current.

So there you have it- power production in a paragraph (or several :))

Bill736
09-09-2011, 12:19 AM
My first emergency generator was a 4 cycle unit rated at 1000 watts continuous, and 1100 watts surge. It would not start my refrigerator, athough my refrigerator was a 1974 model, and perhaps less efficient than modern ones.
My second generator was from Sears, with a Techumseh engine, and rated at 5000 watts continuous. Right out of the box, it burned more oil than gasoline, and soon got stored away. My present generator is a Briggs & Stratton branded unit, rated at 5500 watts continuous. It starts on the first pull every time, and runs flawlessly. I've found the easiest weather enclosure for the generator is two 6 foot long by 4 feet high pieces of plywood, hinged along the tops along the 6 foot length. I unfold it like an "A" shaped puptent to cover the generator, with the exhaust pointing out one open end. The cover is inherently wind resistant, and has worked well even during a hurricane.

Joel
09-09-2011, 03:15 AM
Thanks for the info, and for the heads up.

FWIW to anyone who bought or is thinking about buying one of these, the voltage AND frequency change with rpm. I raised the governed speed and was able to get the voltage a bit better. Originally, the freq and volts were low, so I cranked it up until the freq was 61Hz (was 59Hz), which helped the low voltage situation. Still not perfect, but improved.
I believe I need to be careful not to exceed 61Hz?

jobs2250
02-25-2013, 06:53 PM
I had a similar problem with 240V - only ouputting around 200V
I found the adjustment screw under the fuel tank (RHS) just above the pull start).
It now puts out about 250V unloaded and 235V loaded.

The Artful Bodger
02-25-2013, 08:30 PM
I believe I need to be careful not to exceed 61Hz?

It is my understanding that low frequency is more of a problem than high frequency.

J Tiers
02-25-2013, 08:43 PM
Low VOLTAGE is a problem..... low frequency can be one.

Low frequency can draw more current, because the inductance may not be sufficient, and back EMF of the motor is lower.... equals "draws more current", and small generators are somewhat limited in current. But the "more current" is typically only a little more, and a fixed amount more, so the "system" tends to be stable at a bit higher current.

Low VOLTAGE also causes motors to draw more current for a given power output, but it's generally a worse problem. Small gennys are limited in current, so that can be a feed-back... low voltage draw more current, which lowers the voltage, which draws more current........which lowers the voltage even more..... and so on.

For a good example, run your air compressor on a long extension cord.... it probably will not start, and likely will pop the breaker.

if the genny can hold up voltage, then the feedback doesn't happen.

darryl
02-26-2013, 12:24 AM
Just an idea- a small genny could be bolstered by adding a flywheel and having a means of temporarily increasing the field current. When a motor starts, it would tend to drop the rpm and the frequency, but the flywheel would lessen the effect of this. With the added field current, the generator would be capable of giving out more of a surge to help get that motor up to speed. Whether this would make the genny heavier than a higher rated model, I don't know. I know there's going to be some maximum current/voltage product available from the generator portion, but I'd bet that most are good for considerably more than rated power on a temporary basis. I'm not aware of any generator that uses this idea, but offhand it does seem like a good way to handle motor starting loads.

If generators were built 'inside out', like some model electric motors, your extra flywheel effect would already be there, without the need to add weight.

The Artful Bodger
02-26-2013, 12:31 AM
Darryl, some no break power supplies, for places like hospitals and airports, had a massive flywheel that was being continually rotated by a mains driven motor. When the mains failed the flywheel was engaged to start a diesel that in turn drove the flywheel and the motor that then functioned as a "generator". In a good system the lights did not even blink.

One variation continually turned the diesel with exhaust valves held open, I understand the diesel engines did not really like that life and the system was deemed unreliable.

armedandsafe
02-26-2013, 01:02 AM
We used those no-break diesel generators on White Sands Missile Range back in the 60s. The only problem I ever had with them was a new guy who went out to do the monthly run-up test and exercise operation. The frequency indicator was vibrating reeds. The speed was to be set to make the reeds saying "60" stationary. I noticed that things were looking pretty strange in the comm center, so I went out to check. I knew immediately that the generator was not sounding right. Upon inspection, I dropped the generator speed back to the 1200 RPM level it was intended to run and the proper reeds stabilized again.

Vibrating reeds will stabilize at 60Hz AND at 120Hz. :D

Pops

oldtiffie
02-26-2013, 01:29 AM
I have a "Honda" EU201 generator:

http://powerequipment.honda.com.au/Super_Quiet/EU20i

Here are tables of typical starting and runing loads:

http://powerequipment.honda.com.au/FAQ_Generators

Recently the electical utility supplier (with notice) cut off power here (pre-planed maintenance to the reticulation service) on a very hot day when we had guests for lunch.

The generator ran 3 refrigerators and 3 fans and never missed beat - very impressed - but I did not have it on "Eco" mode as it idles at a lower speed and needs a lot more torque to get up to standard speed (50Hz) - so "standard speed" it was (at 50Hz).

I run heavy electrical tools (drills, chain saws etc.) and never a problem and at 20Kg (say 45 pounds) is easy to move around - fits easily into a builders barrow or on the from of the "zero turn" mower.

It has allowed me to almost get rid of many of my air-driven and battery-operated tools as well - some elctronic stuff as well - never a problem.

mototed
02-26-2013, 06:14 AM
I bought two of those little generators for work to run fans to help cool off the crew during the summer, and to run small sump pumps. I changed the spark plugs to NKG, and the other mods, ( I think it was fuel line replacement) before I ever pulled the rope. Ran them 10 hours a day,7 days a week for 3 weeks. At 1/2 load they burn right at a gallon in 8 hours.

Not bad little units at all, They do take a little while to warm up.

For storage after the job, i dumped the leftover fuel back in the can and ran them till dry, but I do that to all my two stroke stuff anyway.

macona
02-26-2013, 06:15 AM
There are also power conditioners that use the flywheel method. Massive 3 phase motor and massive 3 phase alternator with a huge flywheel in between. Smooths out a lot of line issues, I believe they are used in semiconductor plants where line quality is very important.

vincemulhollon
02-26-2013, 10:13 AM
Refrigerator (frost-free, 16 cubic feet) = 725W

Yikes how old is that thing, guess is 80s era? I know my new fridge draws less than half what the 15 yr old fridge drew. Off the data sheet mine draws 150 once running and peaks at 450 when starting up.

Interestingly you may find it cheaper (especially in the long run) to buy a newer more efficient fridge than a bigger generator.

I'm quite certain my mom and dad's 1970s fridge was drawing about 30 amps to start, because it was dimming the lights just as bad as the air conditioner dimmed them. Those days are long gone of course.