RE: Generator Questions

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firefighterjake

Minister of Fire
Jul 22, 2008
19,588
Unity/Bangor, Maine
Bought a new Yamaha generator . . . have some questions that I figure you folks might know the answer to . . .

1. It has a ground earth terminal. Am I supposed to hook this up to something or am I good to go with the generator as is?

2. There is a voltage adjustor . . . do I need to fiddle around with this . . . and when would someone do so?

3. There is an economy switch where the generator kicks back to half speed and power output . . . I assume this is to run light use electrics such as lights, but not the freezer, refrigerator, well pump, etc.?

4. I'm running ethanol free fuel in it for now . . . for long term storage the manufacturer recommends running it dry and shutting off the fuel. Is using fuel stabilizer also fine? Preferences?
 
Bought a new Yamaha generator . . . have some questions that I figure you folks might know the answer to . . .

1. It has a ground earth terminal. Am I supposed to hook this up to something or am I good to go with the generator as is?

2. There is a voltage adjustor . . . do I need to fiddle around with this . . . and when would someone do so?

3. There is an economy switch where the generator kicks back to half speed and power output . . . I assume this is to run light use electrics such as lights, but not the freezer, refrigerator, well pump, etc.?

4. I'm running ethanol free fuel in it for now . . . for long term storage the manufacturer recommends running it dry and shutting off the fuel. Is using fuel stabilizer also fine? Preferences?

We don't know the model but since it has an economy mode I'll have to assume it's a 120 volt inverter model. That's great. They're really so much better.

1) Ignore the ground terminal. Often debated by academics, in real life, almost nobody has ever attached a ground rod to a portable generator.
2) The inverter has very good voltage regulation electronics. Check voltage one time, be sure it's 120, and then act like it isn't there. I've never seen this adjustment on an inverter genset but have often seen it on non-inverter sets and had to adjust it. Even then it was a one time thing.
3) The economy mode on an inverter set reduces rpm to match the load. It's not a 50% thing but varies based on load all the way up to full rpm and full output. There are some non-inverter sets that idle down when no load is detected but then rev up to full rpm when even a little light bulb is turned on. Inverters are awesome because of this. Reduced noise, reduced fuel use, increased engine life.
4) All of these generators are rated to run on regular fuel with ethanol. Every time I shut it down for more than the day I turn off the fuel and run the carb dry. Top off the fuel tank. All of my fuel has stabil added.
 
On fuel storage, like so many others with their own systems, I believe mine is best. You judge for yourself, but this is what I do:

1. If tank has more than just a gallon or two left in it, I disconnect hose downstream of fuel shutoff valve, and drain it back into one of my gas cans. From a better authority than me, “No chemical agent or fuel additive can be added to E10 gasoline, in a reasonable quantity, that will fully prevent phase separation or recombine a phase-separated layer. The lower “phase separation” layer will be a corrosive mix of water and ethanol.”

2. If there is just a gallon or two of fuel in the tank, enough that I’ll be able to put mostly fresh gas in it the next time I need it, I just add a cap of stabilizer to the tank, run it thru a little, then shutoff the fuel valve and run the carb dry.

3. I open the drain cock on the carb float bowl, and drain that last 2 oz. of fuel from the carb bowl. If your carb doesn’t have a drain cock, you can just loosen the screw in the bottom center of the bowl, and let it drain out thru there (less neat).

4. Drain engine oil, and fill with fresh oil. I don’t care if it only ran 2 hours, I don’t know how long it’s going to sit before I run it again, and I want the corrosives out of the crank case. The fraction of a quart of oil that my generator holds isn’t going to break the bank, even if I change it after each use.

If you follow this, you have the best chances of your generator being ready to work the next time you need it, whether that’s next year or in four years.
 
1. It has a ground earth terminal. Am I supposed to hook this up to something or am I good to go with the generator as is?

You really shook hook up to a grounding rod, but in practice I don't think most folks (including myself) do this, though I actually thought about this the other day and was looking at grounding rods on amazon


2. There is a voltage adjustor . . . do I need to fiddle around with this . . . and when would someone do so?

Perhaps to fine tune if using the generator to power sensitive electronics? Though I believe the issue with electronics depends on whether or not the generator produces a modified sine wave or not in terms of voltage output.

3. There is an economy switch where the generator kicks back to half speed and power output . . . I assume this is to run light use electrics such as lights, but not the freezer, refrigerator, well pump, etc.?

Likely what Highbeam noted. May also be simple a function that lets the generator idle when no load is detected. Mine generator has this feature.

4. I'm running ethanol free fuel in it for now . . . for long term storage the manufacturer recommends running it dry and shutting off the fuel. Is using fuel stabilizer also fine? Preferences?[/QUOTE]

I run mine dry after every use (close valve on fuel supply line) and only keep treated fuel in the tank. This is rotated out if not used; also let the generator run for half hour every few months.
 
If it’s a typical Yamaha inverter with eco throttle it will only hold 1-2 gallons and the carburetor is inside the enclosure. This would not be an open frame genset but a lunchbox genset.

@begreen has a yammy inverter genset. Maybe can share his experience with this voltage adjustment.

Also, FYI, Costco started selling a generator with a Yamaha engine that is an oddball generator. Not a Yamaha generator but a Yamaha engine. Seems Subaru small engines were bought and relabeled as Yamaha.

What do you have Jake?
 
Yamaha bought the Subaru line of small engines when Subaru made the decision to exit the small engine market. Yamaha is continuing just a few models.
Subaru also exited the car market stateside at about the same time.
 
Subaru also exited the car market stateside at about the same time.
What?? Where did you hear this? Subaru is not leaving the US car market to my knowledge. Seems like every 3d car out here is a Subaru.
 
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Oups screwed up it was Suzuki that left auto market.
 
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Ah yes, Suzuki. That is one brand I have never owned.
 
Regular generator . . . 7200DE.
 
74.5 decibels! Whoa. This is not an inverter genset.
 
74.5 decibels! Whoa. This is not an inverter genset.

I traded in my original generator on one with a Honda GX engine, because my first generator was just too loud, it got annoying when we had to leave it running all day during extended outages. My current generator is very quiet by comparison, so I just looked it up, and it’s listed at 79 dB. So, if that reference point is accurate, 74.5 dB seems downright quiet, but I suspect the listing of my generator might be an error.

https://www.homedepot.com/p/PowerSt...with-Honda-GX390-Engine-PS906811P-H/204401587
 
Big open frame gensets are almost always very loud but sometimes you need the power. Not many 240 inverter gensets available.

The decibel scale is a log scale so every 3 dB is a doubling of sound. The famous Honda 2000 genset is now less than 50 dB, my backup 3000 watt genset is just over 50.

If sound matters to you, and power quality matters then an inverter genset is the best way to get there but they do cost more!
 
Watching family members dealing with Florence reminded me to exercise the Yamaha. Most of the hours on it so far have been for exercise, but that's ok.
 
In the country . . . and if I'm without power, chances are everyone around me will be without power and running generators. Sound was a very low concern as I was looking more at the amount of power, reliability, fuel usage and all at a price point I was comfortable with . . . hence the Yamaha (although I was sorely tempted by the Honda generators -- they were just too expensive to justify the cost.)
 
Update: Came home on Saturday evening to find the house without power after a strong cold front breezed in, knocking over trees and large branches.

Hooked up the Yamaha generator, plugged into the house, threw the main breaker, slid the interlock device and flipped a set of breakers to supply the whole home with juice . . . worked great. Much cheaper than a whole house, automatic generator system . . . a little more work . . . but a lot cheaper.

Generator is a bit quieter than my old generator . . . no extension cords running every which way . . . and despite this being a larger generator it seems to be much more fuel efficient than my old Coleman Powermate.

Ran it off and on (no sense running it while asleep or not needing the juice) for 24 hours when the power came back on.
 
Good deal.

We also shut down overnight. The refrigeration systems are fine until morning, don’t need lights, noise for sleeping, and the running genset is attractive for thieves.
 
Jake, good to hear it worked out for you. What model did you get?

There's no user settable voltage regulator on our Yamaha that I know of, but our unit may be smaller than Jake's. Our genny is setup dual fuel but it's only been run on propane. It's amazing how clean the oil stays. I try to exercise it once every couple months. Not going to change the oil for these 15 minute runs. Once a year is fine. It self regulates itself according to the load.

In an extended outage we only run for a couple hours in the morning and 3-4hrs in the evening with an extended outage unless we know it's going to be a short one of less than 2 days. The primary concern is keeping refrigeration and freezers cold. Everything else is gravy. We have plenty of lights, a rechargeable radio and a propane cooktop to keep the ship running during a long outage. The longest so far has been just under a week.
 
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Yamaha 7200DE . . . my electrician friend took a look at the voltage and said it appeared to be pretty close to what comes in off the lines, although it is not technically "clean" electricity.
 
Ah yes, that's a big industrial model. Mine is about a third that size.
 
Hey begreen, I’ve been looking at the propane and dual-fuel conversions available on eBay, is that what you have? I haven’t pulled the trigger, because none of them look like they’d be a clean fit on my rig, I see some cutting the frame to make them fit and I just don’t want to do that.

I have 500 gallons of propane buried in the back yard, and we really don’t use it for much, so it’d be ideal for me to be able to run the genny of propane.
 
Hey begreen, I’ve been looking at the propane and dual-fuel conversions available on eBay, is that what you have? I haven’t pulled the trigger, because none of them look like they’d be a clean fit on my rig, I see some cutting the frame to make them fit and I just don’t want to do that.

I have 500 gallons of propane buried in the back yard, and we really don’t use it for much, so it’d be ideal for me to be able to run the genny of propane.

Sure beats storing 500 gallons of gasoline! I wish my genset was dual fuel. The new version of my genset is dual fuel so the manufacturers are listening.