power needs

I need some opinions on my power needs.  I am looking into getting an Onan commercial generator.  What should I look for? Should I be concerned with the watts or the amps?  All of my equipment(2-1200w warmer, 1-500w soup kettle, 1-1450w water heater) plus a small fridge and water pump.  Total watts is 4340 and total amps 56.2 for all of my equipment.  Am I good with a 5500 watt generator?  I plan on some lights and later down the road an air conditioner.  Am I good with 5500 or should I go with a 7000watt? 
Is 5500 too big?  Will these pieces of equipment cycle on and off that would allow me to go with even a smaller gen set?

I'm planning on a MINIMUM of 8,000 watts running, 10,000 watts surge power (for AC startup, load spikes etc.) and I might even go bigger - an 80% of my kitchen is propane! 
 
We had a large desert racing team for many years, and we found that you should only run at about 70% of your total genset capacity. So as an example, if I was burning 5,600 watts with everything turned on, I would need an 8,000 genset to have a good safety cushion. Nothing worse than popping breakers, having pistons cook, or turning off important appliances cuz you don't have enough juice...
 
The important calculation here is how much do you need if EVERYTHING IS TURNED ON AT THE SAME TIME!
Then, give yourself an extra 20 to 30% more juice, and you won't be short any time soon.
Dave

I forgot to add, humidity, elevation, ambient temperature, ventilation, etc. all play a part in how efficient your generator is going to be. Just cuz it's rated at a certain power does not mean you are going to get that!
 
That's why car manufacturers say "your mileage will be different"...

7000 watts is a good size,your big appliances will have a surge at start up and then level off,also it wll allow some room to grow with your needs. Oneway to easy power needs on lighting is to use rope lights. easy to hang up and you can link strings together. 18' rope x 2 about 55 watts at a cost of $25.00.

LOL we're gonna look like a small city up here with all my power - hey, maybe we could rent hookups by the hour! 

The one thing you really need to be concerned about is noise and then fumes. I would be pissed if I was to have to listen to a gen set all day long. Have you heard the particular set running that you are looking at? I would recommend something within this noise level 51.5 - 61 dBA. Any higher and you are now a nuisance.
 
I use one of the little Yamaha generators, you need to be right on top of it to even hear that it is operating. http://www.yamaha-motor.c...specs/626/0/specs.aspx
 
I know that if I was to use a contractor commercial type gen set I would be run off of the spot I am set up. I would seriously consider a unit like this, http://www.yamaha-motor.c...elhome/622/0/home.aspx
 
I know they are pricey, but you are paying for quiet. Your neighbors and customers will greatly appreciate it.

The problem with ALL the quiet ones is none of them are very big or powerful.
 
http://www.yamaha-motor.c.../generator/sizing.aspx
 
if you do the math, running even simple stuff like a toaster, the roof air, a hood vent, one reefer and one freezer, and some lights you are pretty much tapped out. You gotta remember that many devices have startup needs vs. running needs. That's why I say I will want at least 8,000 running watts.
 
The quietest genset that will serve my needs (other than the house-power style) I have found is about 70db, I've talked to dealers and they say nothing on the market is quiet if it's bigger than that Yamaha.

localnet

I know they are pricey, but you are paying for quiet. Your neighbors and customers will greatly appreciate it.

 
  They also appreciate the fact that EVERYONE in Alaska has lots of big guns with them at all times...don't think complaining neighbors is really an issue up here. Heck, people drive snowmachines, ATVs, and other stuff up and down city streets and in people's yards and nobody complains...I don't know about over where Roger is, but here in the interior you pretty much do whatever you want.
Dave

chocolategypsy

localnet

I know they are pricey, but you are paying for quiet. Your neighbors and customers will greatly appreciate it.

  They also appreciate the fact that EVERYONE in Alaska has lots of big guns with them at all times...don't think complaining neighbors is really an issue up here. Heck, people drive snowmachines, ATVs, and other stuff up and down city streets and in people's yards and nobody complains...I don't know about over where Roger is, but here in the interior you pretty much do whatever you want.
Dave

 
I know about Alaska, I used to live and work up there, and still have a few guns. I don't know where you are setting up, just stating that many people do not appreciate a loud commercial generator running continually for hours. I know it would drive me nuts having to listen to one all day long in my trailer.
 
And those little Yamaha gen sets can really put out some juice. The little 2000 watt unit I have runs a commercial refrigerator, a separate chest freezer, a coffee pot, a commercial food warmer, sears auto battery charger, vent hood and two florescent lights, all at the same time. I don't know how she does it, but it is the best darn generator I have ever owned, and you cannot even hear it. Runs for 10 hours + on less than a gallon of gas too.
 
And if you are putting in AC, save your money, when everything in your trailer is running, ventilation is your friend. My griddle is rated at tens of thousands of BTU's, and then throw in the steam table, they don't make an AC unit big enough to cool my little trailer. Not that you should need one up in Alaska, but I do remember a few days on the slope that it was so hot it actually shut down a pump station. No one thought to install any means of cooling up there.

My trailer is all electric except for the wood/charcoal smoker and propane stove/turkey fryer.
 
I've got a water pump, heater, fridge, 3 hot food wells and 1 double cold food well, stereo, lights.  Everything running I need 10KW.  I've gotten by for 5 years with a 3000W quiet Honda and couldn't be happier.  All you have to do is juggle your usage and keep the surges in mind.
 
It's great to have a 220V 50A hook up, but you can't beat the size, portability, fuel economy, reliability and most impotantly the quietness of a Honda or Yamaha type gen.  When I first started I bought a big boy gen from Lowes and returned it within a week.  Drove me crazy!
 
I recently added a convection oven and will run it with a smaller 2000W Honda or Yamaha.  I prefer to deal with and have more options with 2 small quiet gens than a big boy.
 

Good info thanks.  "Juggle" you mean maybe turn things on all at different times?  What would be the bigger surge draws?  do you think the warmers would draw the most because they are the largest watt user?  I don't know how often the water heater will cylce but I would think that the lights and water pump would be much to worry about.  I just want to know that I have enough so I don't cook my gen...pretty pricey and very important.

I also have a 3000 watt honda, I'm on 50A service, but only draw 35??... The generator will handle 2 refers and the hood no problem, but if the water heater kicks in when the coffee pot is brewing, kicks the breaker every time. And forget about running the microwave. I have to shut off both fridges to do that.
I still have a 2 bay steam table that I can't use with the generator.
You CAN get by with an under sized gen, but it's a pain!
I'm mainly on generator only 1 day a week, and it's during the colder months, so it's not critical if I rotate fridges on and off, but I would not do it when hot out.
Nothing like the health inspector coming by and your refers are not at proper temp.
When funds are available, I'm going with a 10k generator. I hate being under powered.
I found this one for a grand,  66db, so its fairly quiet, the honda 3000 runs at 49-58db.

chefbuba


I still have a 2 bay steam table that I can't use with the generator.
You CAN get by with an under sized gen, but it's a pain!
I'm mainly on generator only 1 day a week, and it's during the colder months, so it's not critical if I rotate fridges on and off, but I would not do it when hot out.
Nothing like the health inspector coming by and your refers are not at proper temp.
When funds are available, I'm going with a 10k generator. I hate being under powered.

Like I was saying...
Everyone in my family has 2,000 watt Yamaha generators already - do the math....a toaster (yes, the silly little thing that takes two (2) slices of bread is 1,500 watts. My little old coffee pot is 800 watts...and so on, and so on..turn on a fridge (wait, you REALLY think the H.D. might actually want to check temp?) and a freezer, and you are WAY over the output of the cute (and quiet) little Hondas and Yamahas.
 
LOL I bet most of you didnt know that over 1/2 of Alaska has no other power but generators! Hell, half of my 'city' (Delta Junction) isn't on the grid, the folks use old diesel gensets from WWII that the govmint left behind. Noisy, smelly generators are as common as bears up here - meaning they are everywhere.
 
I understand about noise. I also understand that I want extra power when I need it - and the solution is simple. We figured this out years ago, not sure why you peeps haven't taken the mental leap yet.
Listen to a Kohler, Generac or Onan generator next time you are standing by a coach motorhome. What was that? You don't hear much? MmmmHmmm...that's cuz there's baffling, sound chambers (think Bose steroes) and BIG FRIGGIN' MUFFLERS on them. Piece-O-Cake to fit an automotive style muffler to your loud industrial generator and lose about 10db, more if you build a sound baffle box like my smart brother did. He's a long-time Burner and his camp is dead quiet, but he has zillions of watts at all times.
 
Even if I didn't modify the exhaust, I'd still go with big power. I have 50' of 6-gauge wire, put the damn thing behind a rock or in the bushes. So far, I've only seen 3 mobile rigs in the entire Alaska interior, so 'neighbors' don't really exist. And if i did do any vending, it would be at snowmachine races or some other kind of motorsport event, so noise would be the rule, not the exception.
 
Last summer it was over 90 in Fairbanks for quite some time, and over 80 most of the summer. Yes, it gets relatively hot up here. Yes, I will put in a roof cooler, just because.

good points there....go and look at some of the bigger marine units.....they most all come with a sound box/baffling/and great mufflers, that run so quite you can sleep on top of 15k watts while its running..... you just have to do some research, and maybe get a little creative......PIECE OF CAKE !!
 
you can get marine units from around 3.5k, all the way up to 20k, and even bigger..... so finding a box for one on your trailer shouldnt be too difficult

most events that we do states no generators allowed. we only do a couple that use them and most are very loud.

kennyb


most events that we do states no generators allowed. we only do a couple that use them and most are very loud.

Intersting...so do they have power on site? I know that some of the community fairs and such have power, obviously if we do any of those places we'll use it. Generators are destined for remote places, like working the fire camps, hunting trailheads, snowmachine trails, other 'wild' locations.

a couple of good deep cycle batteries, with a tender you plug in every night can take care of lighting and maybe music needs..... also, swap to a 12v water pump, tankless propane heater(fires off of D cell batteries) cough up the extra for a propane fridge, all cooking done on propane, except maybe for sandwich press, coffee maker, and small toaster if needed.....
 
tie your battery bank into the 12v side of a small genset, but you will still need at least 3k unit if you have AC.... but you can put large vents in the roof to vent a lot of the heat, at least it wont build up and become oppressive, your hood fans can be 12v as well.....
a pair of 27 series deep cycles can run a lot of stuff for quiet some time..... or go big and put in an 8D, or a pair of them, and you will run all night long and half the next day before you have to recharge them

Nah, I'll just buy a genset...batteries are a pain, expensive and ad lots of weight. Perfect for a remote Alaska cabin, however - that's what everyone does off the grid.
I'm thinking an Onan or Generac system, the kind in the box - reasonably quiet, low RPM compared to the one-cylinder portables, and extremely durable. I've seen a number of the new mobile kitchen builders installing these on extended trailer tongues. I'm guessing I could have a local welder do the same setup for me.

as long as your using a boxed unit, and maybe using a secondary muffler, i dont see any big concerns with excess noise....
 
as it is, im thinking an extension on my front bumper mounts will be the way i go with my genset, wont be the look im going for, but will keep a lot of room freed up inside the van for other things...... lol, im already wishing i was a couple foot longer !

Genset considerations:

1. Price
2. Wattage vs. needs (type of equipment)
3. Noise
4. Size & Weight
5. Ease of moving
6. "Permanent" installation or do you have to set up everyday
7. Is your concession a 1 person or multi-person operation, if you need more than one person to move the gen?

indycarver1


Should I be concerned with the watts or the amps?  All of my equipment(2-1200w warmer, 1-500w soup kettle, 1-1450w water heater) plus a small fridge and water pump.  Total watts is 4340 and total amps 56.2 for all of my equipment. 

Remember Watts = Amps X Volts
 
56.2 A @ 110V = 6,162 Watts.  I'm assuming that is your surge watts and 4340W is your running watts.  You should be fine with a 5,000W gen assuming you do not start everything at the same time.

Hmmmm...wish I had read this thread a week ago. My electrician said that a 5000W would struggle. He said it'd run the lights and maybe a coffee maker. Also, a guy at work said that he used a 5000K at his house during a storm and he could run his lights but if he wanted to use his microwave or turn on his fridge or use the water heater he had to turn everything else off. He said that if he tried to use any power tool while the lights were on everything would dim way down...SO I bought a 78K...yes, that's 78 thousand watts!!!! I can probably run a city. It's quiet so that's in my favor but it weights about 400 pounds.

78k ?????
holy crap....does it have its own trailer ?
i promise you, that monster weighs more then 400 pounds!
it would have to have at least a 4 cylinder to make that much juice, the engine itself probably weighs in at 400-500 lbs
 
im going to look at a 4 cyl unit next week...i think it should be 15-20k, coming out of an old phone company repair truck, i think the guy is going to want too much for it though.... he is a boater, and thinks everything is on a boat price scale

Are you sure about this?  What brand and model number?  I have a feeling it is a 7800W but maybe your electrician was drinking or something.
 

We got a 7500w Generac for our kitchen rig, and it's quieter than I expected. The surge watts are 12,500 so I'm pretty sure we will be able to run everything we've got and not poop out.
For the 'tow truck' we picked up a used Onan 5500 commercial genset, the kind that hangs on a cradle under the frame rail. This will power the refrigeration system for the reefer box, and I should have leftover juice for a chest freezer, or be able to put my warming box into the dry storage area in case I need more room in the cook trailer. I know two generators is excessive, but here in OutBack Alaska over kill is a pretty good idea...

What do you think about the below generator for running a sandwich prep station, commercial single door refrigerator, DC water pump and steam table?
 
http://www.amazon.com/Hon...1306104823&sr=8-16
 
What size/type circuit breaker would I need?

I'm going to convert a school bus into my food truck. The one I have decided on has undercarriage storage built in and that is where I am planning to put my genset. Should I be able to insulate properly to deaden the noise and still have adequate airflow? Also, the bus has a gasoline engine so should I be able to run a direct feed from the gas tank to the genset?

It will all depend on what type of genset your using and yes you can put a sound deading mat in side one of your boxes, same stuff they use for car stereo deading mats its work real good. Just have the door vented for the generator and the exhaust pipe out the back of the bus and your fuel I'd have in a differnt tank in another compartment and able to fuel for outside. Use a F150 ford fuel tank for the genset. Mike 

I just had my Generac 7500w quiet pack installed with inline fuel hook up and remote start. It is very quiet and plan on building my cabinets around them yet and plan on insulating the inside of the cabinet to further quiet the generator.  Alone it is very quiet.  Sure I spent some big dough but I knew it would be my most expensive piece of equipment but it is also my most important peice of equipment.  It is an RV unit because I didn't want to shlep a 300lb generator in and out of my truck, so this is the direction that I a went and sure I will be very happy.

We got a Generac 7500 unit similar to yours, it has a 12,500w surge load. I've ran it and I was quite surprised at how 'quiet' it is for being a large generator. I definitely won't need to do any modifications! It's 70db by the way, so before you buy the one on the link you sent, see if you can find out how many decibels it is.