which generator mep002 or mep003

[trooper632]

I need some input on which gen would work best for supplying power to a house as backup power, and what I would need to do to be able to hook it up to the house, Would the mep002 or mep 003 be the best if either at all.

 

[Crash_AF]

MilSpec gensets are extremely loud and inefficient compared to their civvy counterparts. A MEP-002 is a 5KW generator, you can get a much quieter and more efficient modern genset for only a couple of hundred dollars. As a bonus, you will get frequency regulation, something neither of the two listed gensets has.

Given those two options, I would go with the MEP-003, it has more reserve capacity and will power the entire house where a 5KW unit will only power some lights and maybe the fridge.

To hook it to the house, you need to have a positive disconnect installed with interlocks to prevent the genset and commercial power from being connected at the same time. You can get either manual or automatic transfer panels to do this job. The reason being is because your main breaker is not a positive disconnect and you could backfeed commercial, causing a lineman to be injured by energizing a downed line.

What you might want to do is call your electric company and request a usage history for your house and figure out what your average consumption is to help you decide what size unit you need. Make sure you account for both winter use and summer use as heat/AC can change the numbers dramatically if you want to power them as well.

Later,
Joe

 

[trooper632]

Hey Joe thanks, I'll look at civy gens, with not knowing the condition of GL gens, i'tll probibly be a lot less of a headache.

 

[Isaac-1]

I have to partly disagree with Joe about being able to find a comparable civilian generator for a couple of hundred dollars more than MEP-002 or 003's are selling for. A modern comparable commercial 1800 rpm diesel generator would be about 1/3 higher KW rating due to the conservative nature of the military rating system, lets say 12.5 - 15KW, looking at one major online dealer (generatorjoe) gives us a price range of $9,000 - $12,000 for both new and used units.

Ike

p.s. there are of course deals to be found much cheaper ebay, craigslist, etc.

 

[Scarecrow1]

I Don't know if you have a natural gas connection in your area. But man o man you can,t beat that setup. The cost isn't bad either , in the 1500 starting range, at least it was a few years ago . I lost my house 3 years ago and boy I do miss the Gen lol. Not Putting down surplus stuff, but Most of the problems far exceed the price diff . But if not then the next step is to call an electrician and have him install a switching station .And as always let them do all the connecting to what ever Gen you buy . This is not a do it yourself project and in most states its illegal to do so .

 

[Isaac-1]

Whole long debates can be made on best fuel source for a home backup generator

Gasoline, does not store well, can be in short supply when needed, but gasoline generators are cheap.

Natural Gas, is easy, no storage concern does not tend to go out except in major natural disasters

Propane, stores better than gasoline, but requires expensive tanks

Diesel, stores better than gasoline (shelf life measured in months, or years if sealed, compared to week or months with stabilizer added for gasoline)

The first 3 are likely to be the most expensive to run, natural gas in particular can be a shock to the wallet since most people don't keep a close eye on the meter. I remember as post from another message board last year regarding someone with a 30KW natural gas unit running up a nearly $10,000 fuel bill in 2 weeks during a hurricane outage.

As I see it the biggest problem of any generator that is sold on the "residential" market is the life expectancy almost all of these units are powered by some form of 3600 rpm often splash lubricated lawn mower style engine. These engines have a typical life of around 500 run time hours, which may not sound too bad until you consider there are 168 hours in a week (when Hurricane Rita came though here in '05 even 90 miles inland most people were without power for over a week, many for 2-3 weeks, and some for over 2 months), if that number is not bad enough, consider these units typically auto start and run for 30 minutes per week to keep the batteries charged, and engine ready to go, that alone is 260 hours over 10 years.. Another big downside to these splash lubricated units is the 25 hour oil change interval, so even if you have natural gas coming to your house, how many gallons of motor oil do you have on hand?

Ike.

p.s. note most commercial and industrial generators either natural gas or diesel tend to run at 1800 rpms, with a service life of 5,000 - 10,000 hours between rebuilds. They also tend to have 100-200 hour oil change intervals or longer

 

[steelandcanvas]

Good thread, lots of different opinions here.

 

[jbk]

i have a couple 002s and their tough as nails have good voltage regulation and use .54 gph of fuel not bad if you ask me 78db at 25 ft.. mine can power 3 ac units a 14,000 and 2 6,500 a freezer and fridg. never going beyond 65% load. if you live in close quarters then you might consider a 4 pole gas unit their quiet and cheap. the 003 uses 1.1 gph and would power you central ac or heat. just my two cents.

 

[Carl_in_NH]

I'm with Ike on this one. I also take issue with the comment about military gensets not having frequency regulation; they have mechanical governors - just like almost every generator built for the last 60 years or more. These hold the frequency to well within a couple Hz under most all conditions once the genset warms up. The military generators are as good or better than any typical civilian 'big box' emergency generator - if not considerably better.

Where they also excel is in the fact they have voltage regulation; almost every portable emergency generator powered by a one or two cylinder splash-lubricated engine will not have any electrical form of active regulation; the MEPs are regulated with adjustable output, the civilian units are not. There are, of course, exceptions to this rather broad-brush statement - but generally speaking, under any given load condition, you get what you get from one of these smaller civilian gensets for output voltage, and that's that. The counter argument would be that there's less to go wrong with the civilian set that doesn't have an external regulator circuit.

I've bought two surplus gensets from GL - an MEP-003A, and an MEP-017A; one diesel, one gasoline powered, for all the reasons mentioned above. Having more than one source of backup power when the chips are down is smart so that you can ward off a single point of failure mechanically, and also use different fuels in the event of a shortage.

I also have two civilian sets; one I bought after last year's ice storm where we went without power for a week, and the one that I used during that outage. The one I had during the storm I've had for a number of years, and didn't have even 10 hours on it before the storm started (and was well maintained). That 'industrial' Briggs-powered big box genset is worn out after that one storm; it consumes quite a bit of oil (IMO), and suffered mechanical (starter) and electrical (field cap failed open circuit) failures during the power outage. These things are made for a price, and reflect that.

The military generators were also made for a price - albeit a much higher one, and it shows. All you have to do is turn a wrench on both military and civilian gensets and you'll find that out pretty quickly. Is it all rosy for the military sets? No, it's not; these are 25 years old - or more (and sometimes much less given rebuilds). Parts can be much harder to find; my 003A had an IP problem when I got it, and ended up costing me more than $200 to get it up and running once I found people with the proper parts. OTOH, the 017A has a rusty carburetor bowl from condensation; while I was able to repair it and return it to service, I was also able to get a brand new one in the box for $39 from Saturn. These older generators will likely last longer than I will if given proper care, and a service interval that's reasonable. They are also not as good at being miserly with fuel as a new set civilian set might be; after all, these new light weight sets are not turning nearly the same rotating mass - both in the engine and the generator head - that the military sets are. That takes fuel.

You can probably tell that I've got a bias towards the military sets. In my case, and given my love of tinkering and maintaining such machines they fit the bill very nicely for my application - which is emergency power in New England for an average sized house. Your application might be very different - so you've got to take that into consideration as to the suitability of such a machine for your particular needs.

You've also got to consider what you're willing to spend. I suspect you can gen an excellent civilian generator that will be the match for a military one in all respects - but you're not going to be finding that for $1000-$2000 at Home Depot.

You need to evaluate this overall, and purchase what suits your needs best. My only recommendation is that if you're going to rely on this to keep your family and home safe in a set of circumstances where no replacement generator can be purchased at any cost (see ice storms and hurricanes, where there's nothing to be found on the shelve for 500 miles), then by all means don't have just one. These are electromechanical systems that will fail at some point - typically only when you need them most (after all, that's why you're running the thing instead of sitting inside running off the grid and drinking a beer). Always have a back-up for your back-up if it's humanly possible.

 

[rat4spd]

Starting current is where your civilian units will fail you. A MEP 003, although rated conservatively at 10KW, with a realistic output of around 14KW will start upwards of 20KW. Show me a comparable civilian unit with a 100% reserve starting capacity.

It is not enough to take into consideration only your running load when sizing a generator unless you are running all resistive loads.

I had my 003 hooked up to the house in the summer, with the central A/C on, three fridge/freezers, two window air units, the 2 ton A/C unit in my shop with all of it's lights on and it never even burped when I threw the breaker. It cycled from 25% to about 50%.

 

[Isaac-1]

rat4spd, there are some good commercial units out there that do stack up well against these MEP-002, and 003's, one that comes to mind is the older Onan J series which shares the same basic engine block with the 002/003, specifically the RDJF (radiator cooled version of the same block as the MEP-003) mated with a generator end rated at 17.5KW. Or as a more modern impressive looking small (by industrial standards) unit , see the Kohler 15REOZDB ratd at 15KW standby and 13.5KW prime its a close match for the MEP-003 in specifcations. With its permanent magnet exciter it is rated to maintain a direct short up to 300% output amps for 10 seconds. Of course your not likely to find one of these in your local big box store either and it is probably not built as tough as the MEP's, but its close..

ike

 

[rat4spd]

rat4spd, there are some good commercial units out there that do stack up well against these MEP-002, and 003's, one that comes to mind is the older Onan J series which shares the same basic engine block with the 002/003, specifically the RDJF (radiator cooled version of the same block as the MEP-003) mated with a generator end rated at 17.5KW. Or as a more modern impressive looking small (by industrial standards) unit , see the Kohler 15REOZDB ratd at 15KW standby and 13.5KW prime its a close match for the MEP-003 in specifcations. With its permanent magnet exciter it is rated to maintain a direct short up to 300% output amps for 10 seconds. Of course your not likely to find one of these in your local big box store either and it is probably not built as tough as the MEP's, but its close..

ike

I should've clarified like a previous poster had said.....you're absolutely right that they do exist, but are probably out of reach for the average consumer.

 

[Orionspath]

Great Information! Supports my decision to go with the mil genset (s). I will pass this thread to a few select buddies......Shhhhh!

 

[rat4spd]

Great Information! Supports my decision to go with the mil genset (s). I will pass this thread to a few select buddies......Shhhhh!

If you are going to be relying heavily on a mil set for backup, heed the advice given and have a spare. They, like dueces, are generally middle aged, and parts can be hard to find.

 

[Isaac-1]

As I see it the need for proper spare backup generator is important regardless of the vintage of the primary generator as during a real disaster parts are likely equally unavailable for both new and old generators.

Ike

 

[Csm Davis]

forget kw compare amps and remember the military gen set is rated at .80 not max like the civi ones. Now most of all ask a licensed electrician to check what you plan on doing , because you can kill yourself or a lineman or your whole family!

 

[Speddmon]

This thread was answered pretty well in all. But some things should also be added to what Isaac said about the different fuel types available. In particular the reasons why diesel is such a good choice for a generator.

To visualize the main reason to go with diesel as your fuel source, you need to look at the equivalent BTU/Gallon between the different fuels.

Natural Gas on average has 75,000 BTU/Gallon or is equivalent to 1.58 US gallons of gasoline (BTU's)

LP Gas has about 84,300 BTU/Gallon or is equivalent to 1.35 US gallons of gasoline (BTU's)

Gasoline on average (between the summer blends and winter blends) has about 114,000 BTU/Gallon

#2 Diesel on the other hand has 129,500 BTU/Gallon.

The above, combined with how well diesel fuel stores, makes the arguments for other fuel types over diesel a hard sell. If you look at the modern "tri-fuel" generators, you'll see that the information above is reflected in the 3 different KW ratings of those types of generators...the lowest rating being run on Natural Gas.

Given those two options, I would go with the MEP-003, it has more reserve capacity and will power the entire house where a 5KW unit will only power some lights and maybe the fridge.

i have a couple 002s and their tough as nails have good voltage regulation and use .54 gph of fuel not bad if you ask me 78db at 25 ft.. mine can power 3 ac units a 14,000 and 2 6,500 a freezer and fridg. never going beyond 65% load. if you live in close quarters then you might consider a 4 pole gas unit their quiet and cheap. the 003 uses 1.1 gph and would power you central ac or heat. just my two cents.

I have to agree with jbk on this point, the 5 KW 002a will run a lot more than just a few lights and a fridge. Just doing the math for the lighting alone 5000 watts equates to over 80 regular 60 watt light bulbs....how many lights do you have in your house???? Plus that is a military rated 5 KW, so you're good to use the FULL 5000 watts 24 hours/day 7 days a week

Starting current is where your civilian units will fail you. A MEP 003, although rated conservatively at 10KW, with a realistic output of around 14KW will start upwards of 20KW. Show me a comparable civilian unit with a 100% reserve starting capacity.

It is not enough to take into consideration only your running load when sizing a generator unless you are running all resistive loads.

I had my 003 hooked up to the house in the summer, with the central A/C on, three fridge/freezers, two window air units, the 2 ton A/C unit in my shop with all of it's lights on and it never even burped when I threw the breaker. It cycled from 25% to about 50%.

rat is definitely right about this point, the military sets are very under-rated as compared to a civilian set. Although I would argue that the starting capacity of the MEP 002a or 003a would be closer to about 300% of the full load rating of the set (15 KW and 30 KW starting capacity). I say this for a few reasons, one the leads coming out of the generator head are way larger than they need to be, and are even much larger than a comparable civi generator, so they can handle the starting current. Also, the starting capability of a generator lies as much in the wiring of the head as does the HP of the motor driving it; because the starting load is in reality only there for a fraction of a second, and typically the wiring can handle a short surge like that and still be fine. Your motor on the other hand, is different. If you try to start too large of a load with a generator that will not handle it, then you simply will stall the motor. Where the MEP-002 and 003 have this beat is in the rotating mass as mentioned in an earlier post and in the very conservative HP rating that the military gave these motors. As a rule of thumb, you need 2 HP per KW of generating capacity. I believe the equivalent civilian Onan generator to the MEP-003 is a 12.5 KW. Using the rule I just mentioned, that means about 25HP. Now, the MEP-003 doesn't really have a direct civilian equivalent, due to the fact that the 12.5 KW Onan has a 3.25" bore in the cylinders, where the MEP-003a has a 3.5" bore. This means more fuel/air mixture, and more HP...so taking all of that into account, I would give the starting capacity rating of the military sets a little higher than what rat4spd does.

 

[glcaines]

I recently picked up a MEP-003A GenSet from GL mounted on a M116A2 trailer. I picked it up at Fort Jackson. It was in extremely good condition and fired right up. The trailer even had two new tires and a new cover.

I found a new square-D 400 amp 4-pole manual transfer switch on e-bay for a ridiculously low price. It is being hooked up to power my whole house. It holds the frequency very well and always starts easily. The only complaint is the noise level, but I can live with that.

I love the fact that it is trailer mounted, because I have pulled it to several locations on my property and elsewhere for portable power.

Blue Ridge EMC sent some people out to look at what I had and they all wanted information from me on how to bid on generators from GL.

I would highly recommend the MEP-003A GenSet.

 

[Speddmon]

forget kw compare amps and remember the military gen set is rated at .80 not max like the civi ones. Now most of all ask a licensed electrician to check what you plan on doing , because you can kill yourself or a lineman or your whole family!

The military took into account the .80 (80%) power factor rating, that's why the set is rated for 10KW at 80% PF. The TM states "A 0.8 power factor load equals a 100% meter reading for maximum rated load. A 1.0 power factor load equals a 80% meter reading for maximum rated load"

 

[Isaac-1]

Speddmon, this may be getting a bit off topic, but Onan did make a 3.5 inch bore J series diesel engine in their civilian models, the 17.5RDJF, the big difference between this and the MEP-003a engine is the RDJF is a water cooled block.

Ike