Anyone know where a good generator FAQ is located?
My wife came to me today and said she wants to buy a generator to power the house if we loose power. I'm afraid I don't know anything about wats and volts and tying the generator into the house power.
I would prefer a diesel generator since the fuel stores for a long period of time and my truck an tractor use diesel. Any suggestions?
Re: Generator FAQ?
Re: Generator FAQ?
I ended up with some no name brand gas thingy. It was my wifes idea during the Y2K crisis. It came in handy this last snow. First time I had used it in three years. [img]/forums/images/graemlins/smile.gif[/img] Anyway, I think we spent close to 800 bucks on it. Hmmmmmmmmm.
When I tried to start it, the engine was froze. I had to open it up and take a hammer to it. No kidding. [img]/forums/images/graemlins/confused.gif[/img] Anyway, it powered the woodstove, the TV, a few lights and charged the batteries all up. We moved into the basement for about six hours. The major thing was the Heat!!
My point is, I really don't think it was money well spent. But it does give me the secure feeling, knowing it is available.
Our electricty around here is spotty during storms. Heck today we lost power for three hours. Must be getting ready for the big one. [img]/forums/images/graemlins/smile.gif[/img]
I would say take a good look at your survivalist skills, cause they do run some change. [img]/forums/images/graemlins/grin.gif[/img]
Re: Generator FAQ?
I would have agreed with you if I hadn't experienced an ice storm in 1991 in which we went without electricity for 10 days. Why didn't I just go out and buy one at the time? They were simply not available in the area because of the incredible demand. I have one now, and have never used it, but I am not sorry that I bought it.
Re: Generator FAQ?
Check with Trev, he's an expert on volts & watts, and owns one BIG moma generator.
Ask him about 200 amp services too.
Re: Generator FAQ?
I hear ya on demand, I work at a big box and during the recent ice storm, the store sold over 400 generators inside a week. The moral is, plan ahead...
Re: Generator FAQ?
</font><font color="blue" class="small">( Check with Trev, he's an expert on volts & watts, and owns one BIG moma generator.
Ask him about 200 amp services too. )</font>
This is the first post I've seen from Franz about generators that contains a completely incorrect statement! [img]/forums/images/graemlins/laugh.gif[/img]
I don't know squat about this stuff.. but I do have a setup now that will power the house from the tractor.. and it works!
Check out the thread a while back about PTO-driven generators, and note Franz' suggestion about using an Amprobe on your service to see how much your house is really drawing before you decide on the generator you need.
And note his comments about 200-amp circuit upgrades being the oldest trick in the book that electricians use to make bucks. [img]/forums/images/graemlins/mad.gif[/img]
Let's just say that we now have plenty of generating power, given our needs. [img]/forums/images/graemlins/blush.gif[/img] [img]/forums/images/graemlins/grin.gif[/img] Once I build the moat around the house, heated of course so the alligators and pirannha are happy, and I have the drawbridge with those big motors to raise and lower it, and I install the roof mounted lasers and particle beam weapons, I may be happy I have so much generating power. [img]/forums/images/graemlins/tongue.gif[/img]
No, seriously, we can power everything in the house, for a long time if needed, while the tractor sits in the garage out of the elements. And I don't have an extra engine that needs upkeep and maintenance. I really like the PTO generator setup.. it's on wheels, so I can just tow it to a neighbor's house and power them up for a while during extended outages. I just hook it to the tractor every three months or so and exercise it a bit.. and the tractor gets plenty of exercise all year round. So, when I need power, I can be pretty sure it will work. Not a bad setup!
Re: Generator FAQ?
You have to decide how you want to do switch-over to generator power and how much manual action will be necessary when the power fails and what you want the generator to accomplish.
A few questions for you to think about:
<ul type="square"> [*]Who will do the generator changeover (You, your wife, your children, your neighbors)? Is electrical start necessary or will a recoil start be sufficient? Will you train each person who will do the changeover or should it be 'obvious' with a placard or two?
[*]Is a power failure when the house is unattended a problem? Do you expect the generator to start to keep the heat on in the winter or the sump pump running in the summer if you and your wife are traveling?
[*]How much will you power when the power fails? What electrical devices do you expect to keep working? At one extreme you may have a few lights, the blower for a forced air furnace (or pump for forced hot water heat), a water well, a sump pump. You may want to keep a home office operating, especially of the power failure is several days. You could make more lights available, power the refrigerator and deep freeze. An extreme would be to power almost everything you would use when power is on adding air conditioning, and electrical heat.
[*] Will you maintain the generator and engine yourself or will you want a local service organization? Can your wife fix problems if you are out of town?
[*]What size electrical service do you have to the house?
[*]How many days (or hours) of fuel do you want to keep on hand?
[*]Is someone in the household handicapped and dependent on some electrical device in the house. (e.g. a starclimber chair on the stairway, an oxygen concentrator in the bedroom...)? Could this person be home alone? How will this person do changeover?
[*]Is portability important to you? Will you use the generator away from the house? [/list]
The least expensive generator systems use a portable generator and a manual transfer switch. You go outside, wheel the generator out of the garage, plug a cable from the generator to a receptacle on the house, start the generator, go to your transfer switch and switch from line power to generator power. The transfer switch may switch selected circuits (the little GenTran switches for 6 to 12 circuits) or the entire circuit breaker panel (a 200 Amp 220 volt transfer switch) and select circuits to be powered by turning off selected circuit breakers. This type transfer switch must be sized to match the panel. A 200 Amp service panel will require a 200 Amp Transfer switch.
With the manual system you should start the generator monthly and allow it to warm up, circulate oil and possibly charge a starting battery.
The better and more expensive standby power systems have a generator permanently mounted in a box outside with an automatic transfer switch. The automatic transfer switch detects the loss of utility power, after a short delay (2 or 3 seconds) starts the generator and transfers the load to the generator. When power has been restored the automatic transfer switch switches the load back to the line, allows the generator to run without load for a short time (cool down) and shuts off the generator. Selected high load circuits (e.g. an air conditioner) may be disabled by a relay when the house is on generator power. An alternative is to hook the automatic transfer switch between the main panel and a sub panel containing the circuits to be available during a power failure.
The automatic transfer switch will also start the generator at regular intervals, let it warm up, circulate oil and charge the battery.
Cummins and Kohler both make excellent standby generator systems and have a service organization to install and service the generator.
Northern Tool offers stationary generators in their house brand (made with engines from Perkins, and Mitsubishi) but without a local service organization, you would need to install and maintain these systems yourself.
The manual system is less expensive but changing over to generator power is far more involved. You wife (or children) may not be comfortable doing the switch-over when you are not home. Also if you will be away from home in the winter, the manual system can not protect your house from freezing or flooding (by keeping the furnace and sump pump on).
In other threads on generators recently contained references to a third technique fro transferring the load, a technique to eliminate the transfer switch, Backfeeding the panel from a dryer outlet. Don't even think of doing it. It is unsafe. It may be illegal. It may invalidate you homeowners insurance (it is negligent).
Another generator option mentioned in other threads with an even higher set up time is a PTO powered generator powered by a tractor. This does provide a diesel engine but the tractor must maintain PTO speed as the load on the generator changes. Some loads in the house (computers, clocks and some ac motors) are sensitive to frequency of the ac power. A PTO generator could require that a 3 point attachment be removed from the tractor, the generator attached to the tractor before treating it like a portable generator. Depending on who will do the changeover this is another option. It has the advantage of not adding an engine which needs maintenance to your collection.
The engines used in the generator matter. Cheep generators have cheep engines. With a cheep generator you can be standing in a cold rain trying to start a reluctant engine and still not have a working generator when you need it. The topic of small engine reliability comes up frequently in this forum. I have had very bad experiences attempting to start Briggs and Stratton engines, yet have had no problems with Honda, Kubota, Kohler or Onan engines. (I have a rather extreme position that I will never again own a device powered by a Briggs engine. I realize that this is extreme but it is based on my experience with the engines. )
Look at the manual for the generator. Are there weasel words warning you that the generator must be used outdoors and at the same time must not be exposed to rain and snow?
Electrical power and generator capacity is usually measured in VA (the product of volts and amperes). With Alternating current this is not quite the same as Watts, as it would be for a Direct Current circuit. (Basically with AC the characteristics of the load control the phase relationship between of the voltage and current. The VA measurement ignores this phase angle while Wattage takes phase angle into account. The Wattage is therefor dependent on the characteristics of the load.) Frequently the unit Watts is applied incorrectly.
The generator will provide 240 volts with a center tap providing 120 volts between each hot leg and the neutral. This is the way your electrical power comes from the electric company. With the generator and especially with a small (few circuit) transfer switch you must balance the 120 volt load between the two hot legs. In your breaker panel this corresponds to the columns of breakers. It is not terribly important to balance the load to the power company so the circuits in your panel may not be balanced.
You should size the generator for the maximum load you expect it to carry. This will be below or equal to the size of the electrical service to your house. If you have 200 Amp service you would need a generator of 240 Volts * 200 Amps = 48,000 VA (48 KVA or improperly 48KW). Unless you are planning to keep everything in the house running including air conditioning you will get by with a smaller generator.
Remember the size rating for the generator assumes that the load will be a 240 volt load or a perfectly balanced 120 volt load. The meters measuring current for each hot leg on the GenTran transfer switches is a big advantage. With the whole house (panel) transfer switch and a generator smaller than the house (panel) capacity it is a good idea to also install current measurement when installing the transfer switch. (Such as an amprobe on each hot lead.) For example a 6000 VA generator used for 120 volts only, will provide a maximum of 25 amps on each hot lead. If your circuit is unbalanced and you only draw 10 amps on one hot lead, your total output of the generator is (120 * 10 + 12 * 25) 4200 VA. (You can not draw 'extra' on one lead if you draw less on the other. The limit is the limit.) If you can not balance the load you may need to move up to a larger generator.
The portable generators are typically gasoline powered. These units will range up to 10000 VA. You can find some of the larger, industrially rated portable units with a diesel engine but these are very expensive units when compared to the gasoline generators, even the industrially rated gasoline generators.
The stationary, installed units are available in gasoline, diesel and gas (natural and LP).
Diesel and gasoline are both subject to condensation of water in the fuel tank, and bacterial contamination.
The most convenient fuel to store is LP gas. With one or more underground 1000 gallon Propane tanks you can have several days to a week of fuel. The propane company will fill the tank and keep it full. I don't have experience with the 10 day blackouts but my guess it that it will be easier to get a Propane delivered than to find a gas station with power.
Diesel is second in convenience. A Fuel oil tank to feed the generator and delivery of fuel oil can approach the ease of Propane. I would worry about long term storage of diesel even with a anti-microbial additive. I would burn off all the diesel fuel/Fuel oil at least once a year and refill with fresh fuel.
Good values in portable generators are the combination welder/generator units available from Miller and Lincoln. For example see the Miller Generator Page. These units are very good quality and are very reliable. The downside is that these generators are heavy and will require some effort to move the generator cart. (You can also see from the Miller site that a diesel engine will just about double the price of a generator. )
I recommend that you avoid the 6 to 12 circuit transfer switches - I have discovered that as carefully as I picked the RIGHT 10 circuits, I was wrong. I have had an electrician change circuits once and I am wrong again. A whole house transfer switch would have been a better choice ( at about the same cost). Switching off selected circuit breakers in the main panel would not have been anywhere near as inconvenient as running an extension cord to power my mother's TV as part of the change-over.
Last summer I got a quote from the local Kohler dealer to install a 45 KVA propane generator, external housing and automatic transfer switch for under $17,000. I have not purchased a stationary generator yet. The worst case for my house is if both air conditioner compressors and the well pump start up at once. Other than this one extreme case this generator is oversize but a smaller unit could trip circuit breakers if the compressors start at once.
I should mention what I am using. I currently have a 6300 VA Homelite generator (with a Honda engine) and the infamous 10 circuit GenTran transfer switch. I picked the Homelite because (at that time) it had the best voltage and frequency regulation of the portable generators. I was not aware of the pricing of the engine driven welder/generators when I bought it. Today if I was getting a portable (with effort) generator I would get a Miller Bobcat with 10,000 VA generating capacity, and get a better generator and an engine driven welder.
I was not all that regular running the generator every month to charge the battery. The battery is now dead and will not take a charge. This has not been a problem since the Honda engine starts on the second pull on the recoil starter. One of my summer projects will be to replace the battery (and possibly fix the charging circuit).
The Homelite manual does have the weasel words I mentioned. Warning that the generator must be used outdoors and at the same time must not be exposed to any rain or snow. If I had seen this before buying the generator I wouldn't have bought it. I set it up in an open garage door when it is raining or snowing. I set it up outside the garage if the weather is clear.
I keep the 10 Gallon gasoline tank on the generator full. In the winter when a power failure is more likely I also keep 2 or 3 5 gallon gas cans full and available. In a power failure I get about 10 hours from each fill of the tank, so I need a run to the gas station the first day and each day of the outage. In 5 years I have not had a problem finding a gas station with power. (The record outage is 4 days 5 years ago.) A stationary generator with a plumbed in gas/diesel/Propane tank would be a big advantage. (It would have been a big advantage, I would never have known about, if I had just gone direct to the Propane powered stationary generator. Between typing lines of this message tonight I am rubbing my sore kneecap which I smashed when I slipped on the ice 5 years ago. The Orthopedist says that the knee will just get worse as time goes by.)
I am tempted to have a manual whole house transfer switch installed but I really need to upgrade to an auto-start generator. My mother lives with me and is partially disabled from a stroke. She is dependent on the lights, stairclimber, TV set.... She can not start the generator let alone wheel it out and hook it up. When I am not in the house I am now dependent on a neighbor coming over and starting the generator for her.
As you have observed a diesel generator would have safer fuel storage than gasoline, but the cost is so much higher I can not justify the price for a portable unit and will go to Propane if/when I get a stationary generator since I already have a propane tank for heating and cooking.
Forgive me this is more a stream of consciousness rather than a coherent article.
Re: Generator FAQ?
Excellant Post! Sure has a lot of insight [img]/forums/images/graemlins/cool.gif[/img]
I have opted for a potable generator, since i would like to use it around the place. I am getting a Bi Fuel setup which will allow me to switch between LP and gas. That should get me the best of both. The kit was about $175.00
(Haven't got it yet, so I can't day how easy/well it works)
Re: Yanmar 5kw Diesel Gensets
I just found these advertised in Rock & Dirt,
5kw, Yanmar engine, electric start, fuel tank & shutdown.
These are portable machines ( if you have a strong back) with cages. I don't know the seller, phone is 863-382-4632
No web site listed.