Suitable generator for home backup?

[Drewster2016]

So I’ve stumbled upon surplus action websites of generators on eBay and that led me to doing some research, is like to price out buying one of these generators to power my home Incase of a power outage.
I used some calculators online and if I want to power everything in my house, I’d need about 13kw, but I’d like to plan for the future, so I’m not sure if a 15 would be a good choice.
So I did some research into the mep 805a/b. But the issues is those are only 3 phase, and my house is 1 phase. Is there anyway to use a 805 in single phase?
In the future I’d be adding central air units (at-least 2) and will need the capacity for those.
So anyway I could use a 805 in my situation? Or am I going to have to select what items I’ll be able to power and go with a 804 15kw?

Thanks! I’m just researching and would love any and all input!

 

[eric67camino]

As I understand it, the 805 can be reconfigured to run single phase. I don't know the specifics, but I believe it looses capacity/output when doing so.

 

[dependable]

If you want to consider some load management during outages, then you migtht get by 803, 10 KW. The are already configured with 120/240V option.

 

[Zed254]

MEP-803A: 60Hz. There are 400Hz generators out there: don't buy one of them. The MEP-803A is a 12.5Kw machine that the government calls 10Kw.

Pricing: Govplanet holds about a year's worth of history on recent auctions - https://www.govplanet.com/jsp/s/search.ips?sort=ad desc&sm=1&l2=USA-CT|USA-PA|USA-VT&k=mep803a&mf=1 I pulled states near you thinking you would want to recover it yourself.

These are surplus units that may or may not have been well cared for. Keep searching the SS site and you will get a good feel for what you can expect....and what to look for. Monitor auctions and you will see what is available and what the current prices are.

 

[Coug]

These units run much better long term if operated above 75% of their rated load whenever possible. So if you can make it work with a smaller unit that's better.
There's also the fact that the larger the unit, the more fuel it burns just to operate.

My opinion would be go with the 15kw, or even a smaller one for now and see what all you can actually do with it. Install wiring for the next size up, and then you can always do a straight swap out if you decide the load management game isn't for you. These things don't seem to go down in value much, so if you're not in an immediate hurry to sell it you can probably get your investment back.
Also, it depends on how you're planning on wiring it to your house. A smaller generator like the 5 or 10kw can be wired in with a pigtail and a manual switch installed into your house panel (depending on design) where a larger unit will require a larger, separate transfer switch, bigger breakers, and bigger wires. Will be a much larger investment.


Another option is to purchase multiple smaller units. This gives you redundancy in case one has issues or needs to be taken offline for maintenance or repairs, and also allows you to tailor the amount of power produced to the amount used. It also means that you can load the generator to peak load capacity depending on the season and what you want to run. Downside is having to wire up multiple circuits, or other wiring changes.

I don't have any aircons, but I can run my house with electric dryer, hot water, and stove off of an 802 5kw as long as I'm not running more than one of those 3 appliances at a time. the rest of the household loads are negligible in comparison, and with newer light bulb technology they don't add up to much.

That 13kw estimate is probably a little high compared to the amount you actually use. Being willing and able to choose what loads you need to run at any one time is a much better choice in this situation considering the size/output difference between the 804 and 805 for what you're trying to do. Plus the added expense of transfer switch rated at 30kw, larger wires, and other factors all increase the expense.

 

[Drewster2016]

If you want to consider some load management during outages, then you migtht get by 803, 10 KW. The are already configured with 120/240V option.

Well the issue is going to be more in the winter, in the winter I won’t have the central air compressors running but I will have the furnace fans and the outdoor wood boiler. So I’d prefer not to do load management if necessary. I’ve looked into standby generators but seeing as I already have diesel onsite for other things it makes sense to go with a old military unit I think

*edit* forgot about the well pump and water softener system.
The other thing I was thinking about was In the future my shop is like to be able to keep that running Incase of a power outage as it’ll be a heated shop

 

[Jericho]

I have been off grid for 26 years , have had plenty of gensets Save some heart ache . get a skid mounted , fuel tank under-neath 22 KW 4 cylinder turbo diesel. Yup they run 12k ish up front, new buy a year old "last years model " some as low as 8 k Generators America in FLA sells plenty . Yes its a bit up front,, PARTS are available every where they are simple and easy to get in to for maint . I usually get 150k hours out of mine , I prefer Mitsubishi engines and also have a John Deere , BUT john Deere engines are made in Mexico, MACHINE WORK IS NOT VERY GOOD, INJECTORS HAVE TO BE HAND LAPPED IN !

 

[fa35jsf]

Let’s start with some basics. Since you said you’ve done research and seem to understand basic electrical terminology then you know your house is set up for 120/240 single phase.

Any machine above a 803 is naturally setup for 3 phase. There may be a way to rewire them, but that might be unnecessary as these machines are generally overkill.

Btw, a 805 is a 30 kw unit, the 804 is a 15kw.

I suggest you take a better look at your true electrical demands and loads. Unless you have a large house I would question your need for 13kw without the ac unit. Bear in mind that NOT ALL of your loads are going to be running at the same time. You won’t have two refrigerators, two freezers, a well, a welder, 5 ac units, etc all running at once, you get the point.

The other thing is these generators really like to run at their top end, meaning they like to run with 70+% load on them. When you run them for a long time with little load you get wet stacking.

Another point is these generators are NOT setup and forget units. Trust me, I’m finding that out the hard way. Most people run their units about once a month to keep things fresh and working.

For load comparison I submit my fathers setup. He has a 803 that will put out 13+ kw.
3200sqft house built in 99.
One 4ton ac unit
One 3 ton ac unit
One 2 ton ac unit
All ac units from 2017.
Electric oven
2 fridges
Lights + electronics.

Everything running above (intentionally at the same time) and it still only draws 80% load.


Sent from my iPhone using Tapatalk

 

[Chainbreaker]

My initial urge was to go with more kW than I really needed. I initially wanted 15 kW but after some research I went with a 5 kW rated generator that is capable of 7 kW for short duration and I am very glad I did. So yes, our temptations are to want to go larger to allow for future needs. However, with more efficient electronics showing up in homes (LED lights vs tungesten, LED vs Plasma/CRT TV's, more efficient HVAC, more efficient washer/dryer, etc.) the trend for consuming more electricity seems to have leveled off to some extent. If your home's needs do increase it probably wont be all that much unless you don't have AC and plan to add it later, or switch from gas appliances to electric (i.e. water heater, etc.)

A wise decision is to figure out what you really need to run during a temporary outage while on emergency power. Also, not all appliances are going to be used simultaneously. If one is concerned about that, there are load management devices for load shedding that can be installed to protect overloading a generator.

The BIG ADVANTAGE of finding the sweet spot of just enough kW output is FUEL CONSUMPTION. Unless you already have a large home heating oil tank or store lots of diesel in a farm tank and routinely burn through it to keep it fresh, the big concern is having enough fuel on hand to make it though an extended outage. My MEP's burn 1/2 GPH at 100% load but average less than that. I would want to stay at a max fuel burn rate of 1 GPH.

Since I bough my generators I've been through 2 extended outages ranging from 4 - 7 days and when weather has you stuck home-bound, fuel supplies start to weigh heavily on your mind...how long is this outage going to last...do I have enough fuel on hand?

Anyway, if you truly require upwards of 15 kW then by all means plan for that by knowing how much fuel you will need are willing to store and keep fresh. Our biodiesel laced fuel does not last as long as straight diesel did years ago.

 

[LEOK]

I think the 802 and 803 are prefect for most homes with moderate load sharing, and manual cutover system. If you need larger and want automatics transfer and exercising along with logs buy a new unit in a nice aluminum/stainless cabinet with dedicated single phase with a digital feedback voltage regulator. $12k will buy a first class 30kva machine.

 

[Slate]

Always get more than you think you need. You can always have extra when you don't need it, but it's hard to get more when you don't have it.

Sent from my moto z3 using Tapatalk

 

[mcii]

In the 800 series the ability to have 1 or 3 phase selectable DOES NOT extend into the 804a/b at all as well the 805 on up, yes an ebay seller is claiming his 804 will do 1 phase, its a lie or outright misrepresentation unless he is using transformers or higher neutral voltages [139] to get the 240 phase to phase.
The MEP-004 WILL or can be pretty easily hooked up for 1 phase operation. BUT once more the MEP-804 up, are wound at the time of manufacturing into a WYE only configuration, wire numbers T10, T11 and T12 are tied together inside and brought out as T-10 only, with extensive effort you can go in and break out T10 11 and 12 apart but it is not a east process and requires re-dipping and insulating as well more interior control logic effort.
You can buy what you want, but nearly every response tells you run emm harder and with more load for best operation, and I support that ...
Yup you can make the case for more KW ability, but who and I forget made mention on the long term fuel consumption Vs. supply on hand for long term outages. go back to KISS buy set up and try the 803 if it does not fit or suit your plan/s and needs, it retains its value and sell it off and buy what ever you think, using all that you will have learned, its near a win win ..
To close this, you have choices, and choices are always good. mac/mc

 

[obijohn]

I have a 3400 sqft house, with heat pump AC plus a gas furnace (I can force furnace-only in 'emergency' mode). Big screen TV, gas appliances, microwave. I have a 6KW/7.5KW 'start' gasoline Troy-Bilt gen set with a Briggs &Stratten engine that has worked well for extended outages here in the Pacific Northwest during winter storms. I had a cutoff/isolation switch installed so that I can run the entire house either on street power or the genset, and use load management via turning off lights and breakers (for the big draws). We can do a load of clothes and watch TV downstairs, or cook dinner using the microwave or TV, lights and heating, or TV and AC and a few lights. Because of the temperate weather here it has worked well for me, when the weather was from high 30s to high 50s. Not a longterm system but enough to deal with multiday outages due to winter storms... every few years we'll lose power from a day to a week or so once or twice a winter. It would also suffice for an earthquake, but I wouldn't want just this as my ongoing power source. The advantage is that wiring to code including the exterior socket and box and the cutoff switch and circuit box work of relocating a few less common circuits to the already-present auxiliary box along with inspection and the genset was under $1K. I am getting ready to install a multi fuel kit so I can run it off of natural gas to eliminate the need for storing a lot of gasoline.

When I was much younger the local volunteer fire department had a military surplus gender that was at least 20KW. It could run the tower-mounted siren, but that would really knock down the generator RPMs. This was on the Gulf coast for hurricane prep, to ensure the station could function as a shelter. Seems like one of these gensets would be massive overkill for most houses.

 

[porkysplace]

Always get more than you think you need. You can always have extra when you don't need it, but it's hard to get more when you don't have it.

Sent from my moto z3 using Tapatalk

With diesel generators you want to match the load to the generator , if you go to much past your load you risk wet stacking the motor .

 

[Light in the Dark]

You owe it to yourself to determine the following:

1.) What MUST you run?
2.) What do you WANT to run?
3.) How LONG do you want to run?
4.) Can you supply enough onsite fuel and supplies to meet #3?

The answer to your real application question can be gleaned by parsing through the above 4 questions. A large genset is great when you have literally everything running during the day under full use. How about at night? What if you are consuming only 2.5kw on a 15kw machine?? Not a good scenario long term. There is never a best of all words... only a best of most worlds. You determine the answers to the four questions above, and a best fit might present itself naturally with those answers.

 

[Guyfang]

As I understand it, the 805 can be reconfigured to run single phase. I don't know the specifics, but I believe it looses capacity/output when doing so.

You are going to have to show me how that works.

 

[eric67camino]

You are going to have to show me how that works.

https://www.google.com/url?sa=t&sou...BMAB6BAgDEAU&usg=AOvVaw1sPoVtz2QpbFIMoT_mFaVL

I personally don't have the experience with it, but I found this when I was looking at one.

 

[Light in the Dark]

You are going to have to show me how that works.

Easy

 

[Light in the Dark]

https://www.google.com/url?sa=t&sou...BMAB6BAgDEAU&usg=AOvVaw1sPoVtz2QpbFIMoT_mFaVL

I personally don't have the experience with it, but I found this when I was looking at one.

00x and 80x are very different beasts. What you can do with the 00x does not carry over to the 80x in this regard.

 

[Light in the Dark]

In the 800 series the ability to have 1 or 3 phase selectable DOES NOT extend into the 804a/b at all as well the 805 on up, yes an ebay seller is claiming his 804 will do 1 phase, its a lie or outright misrepresentation unless he is using transformers or higher neutral voltages [139] to get the 240 phase to phase.
The MEP-004 WILL or can be pretty easily hooked up for 1 phase operation. BUT once more the MEP-804 up, are wound at the time of manufacturing into a WYE only configuration, wire numbers T10, T11 and T12 are tied together inside and brought out as T-10 only, with extensive effort you can go in and break out T10 11 and 12 apart but it is not a east process and requires re-dipping and insulating as well more interior control logic effort.
You can buy what you want, but nearly every response tells you run emm harder and with more load for best operation, and I support that ...
Yup you can make the case for more KW ability, but who and I forget made mention on the long term fuel consumption Vs. supply on hand for long term outages. go back to KISS buy set up and try the 803 if it does not fit or suit your plan/s and needs, it retains its value and sell it off and buy what ever you think, using all that you will have learned, its near a win win ..
To close this, you have choices, and choices are always good. mac/mc

I have seen people say you can pull single phase off, just by tapping two legs of the 3ph configuration. Thats where most of this info comes from, repeated through the internet. Thats why SS and other resources are so essential in making sure the good info floats to the top!