What size generator Do I need?

[time_traveler]

I have a TT 2014 Coachmen Apex with a 13K A/C

 

What size do I need to power everything?

[time_traveler]

Would a 3K generator work?

[AFchap]

That depends on what "everything" is and total amps required. My 7,500 Watt generator will turn out a maximum of 62.5 amps. Watts divided by volts = amps. So for me 7500w/120v=62.5a. OR, calculates how many total amps you need and multiply by 120 and you will know hhow big a generator you need in watts. If you truly want to run "everything" at once, but a bigger one than the numbers indicate.

[time_traveler]

I want to be able to run my a/c and some lights and TV at the same time? where do i found how much amps each device uses?

[AFchap]

Amp draw should be in the specification sheet for each appliance, particularly the ac. The ac may have a label on it with that info. Lights & tv would be fairly low. Flat screen would be lower than a tube type tv. My guess would be an avg ac would pull around 15a. A 3k generator turning out a max of 25a should run one ac unit plus lights & tv. Add a coffee pot or microwave and that would be too much. Remember the refrigerator probably pulls 4-5a too unless you run it on lp. When we are on 30a power we shut down the ac long enough to run microwave or coffee pot.

[time_traveler]

thanks

good info

[Yarome]

A few additional points to consider.

 

1. Your trailers power system capability. I believe your rig has 30 amp service so regardless of the size of generator you purchase, your rig is only capable of dealing with a maximum of 30 amps of incoming current... meaning a 4000 watt generator is going to be about the maximum your rigs internal systems can handle.

 

2. When purchasing a generator, you need to pay special attention to the specifications. There are generally 3 levels of output. Surge, maximum (both for limited duration) and sustained outputs. For an A/C a higher surge rate would be desirable, but you also want to ensure the sustained power output is sufficient. Ie., a 2000 watt generator might surge for a short duration to 2300 watts, with a sustained output of 1600 watts. That would probably be sufficient to run the A/C, a light or two and the TV, however, that's going to be about it.

 

3. Generator sustained usage, cost, and weight. Needless to say.. the bigger the genny the heavier it will be and the more fuel it will consume. What percentage of the time will you actually be running your A/C off-grid? What is the cargo capacity of your trailer? Do you need 4000 watts available at all times? How physically fit are you? Loading/unloading a 200# 4000 watt generator vs. a 45# 2000 watt.

 

What I find that works for me and is a very common setup among boondockers is 2 - 2000 watt portable inverter generators. They can be connected in parallel to double the current, but I very rarely ever need more than one at any given time... a single is capable of providing for my needs 90% of the time. My A/C is also the smaller 13.5k and has a "hard start capacitor" mod so my 2000 watt portable is more than sufficient... not by much... but once the A/C is up and running there is enough left over for a few light (LED's), TV, and satellite receiver.

[chirakawa]

Would a 3K generator work?

 

Yes.

[Kirk W]

I want to be able to run my a/c and some lights and TV at the same time? where do i found how much amps each device uses?

Some things will have a amp rating on the tag next to the power cord, but some will list the requirement in watts. To convert watts to amps you divide the watts by 120V. Thus a device listing 1200 watts of power will dray 10A of current. But it really isn't as simple as that because all devices have a brief period of starting power surge that exceeds that running current which is usually what the label shows. Anything with an electric motor will have a very short period of much higher current draw.

 

a 13K A/C................................................What size do I need to power everything?

That 13K is probably a rated cooling capacity in BTUs.So you will need to convert that into watts. Most RV air conditioners draw between 8A and 13A while both fan and compressor are running. Then you also need to define what "everything" means as your microwave is another very large load, as compared to other things. A generator of 3Kw might run most things but it will not run the microwave and the air conditioner at the same time. It may be able to supply other loads and the air conditioner, if it can deal with the starting surge of the air conditioner. There is much too little information to answer but most do not supply an air conditioner from a small portable generator.

[Ray,IN]

RV appliance electrical consumption

and this from RV education 101, discusses your converter and battery charger electrical draw.

I hope that helps you make your decision between the 3 or 4 low noise level gensets sold today; which IMO are Honda, Yamaha, Boliy, and Generac.

Personally I've owned and used a Boliy 3600SI since 2008. It has better specs than any other genset of the same size.

[kinseypw]

Whatever generator you get, please make it a quiet one. I know that honda and yamaha make very quiet units. i have a champion 3500i that is a little bit noisier but we rarely use it since we have solar. Nothing worse than sitting by the fire on a quiet night and a generator starts up across the lake and you have to put up with the constant drone for the next 5 hours

[Kevin H]

Whatever generator you get, please make it a quiet one. I know that honda and yamaha make very quiet units. i have a champion 3500i that is a little bit noisier but we rarely use it since we have solar. Nothing worse than sitting by the fire on a quiet night and a generator starts up across the lake and you have to put up with the constant drone for the next 5 hours

 

Thread hijack here -- Why are the people with the loud generators the only ones who do not hear it ??? Perhaps their barking dogs are covering it up

[chirakawa]

Nothing worse than sitting by the fire on a quiet night and a generator starts up across the lake and you have to put up with the constant drone for the next 5 hours

 

Maybe trying to sit outside and enjoy a quiet evening and your neighbor starts up a campfire which smokes you back into the house.

[Lou Schneider]

Besides the noise, many construction style generators (the inexpensive, loud, open frame ones) are 120/240 volts.

 

120/240 volt generators have two separate 120 volt windings that are combined to make 240 volts. They cannot be combined into a single 120 volt outlet unless the generator has a switch to convert it from 120/240 volts to 120 volts only. Each winding on the 120/240 volt generator supplies half of the generator's rated output, so a 3000 watt 120/240 generator will only supply 1500 watts (13 amps) on the single outlet that will feed the RV.

 

To use the generator's full output you need either 1) a 120 volt only generator, 2) a switch on the generator that converts it from 120/240 volts to 120 volts only or 3) a 50 amp RV that is wired to utilize both 120 volt circuits equally.

[Kirk W]

Besides the noise, many construction style generators (the inexpensive, loud, open frame ones) are 120/240 volts.

And most of them also have rather poor power regulation since they are not designed to supply today's modern electronic equipment but most are intended to supply things with motors, (saws, drills, & assorted power tools) and things like welders which are not terribly sensitive to poor quality power sources. Most of them must operate at a constant RPM to supply the 60 Hz power that tools require and so are not very efficient.

[time_traveler]

thanks for the input

Buying a quiet generator is the only option for me.

I just returned from dry camping at BLM site near Quartzite I used a friends 2000 Honda and it worked great for everything but the A/C and Micro which i didn't need on this trip. there were several people out there using the open frame loud construction type. I would never own one of those for camping. I would like to buy a generator that can handle both the A/C and Micro not at the same time.

[time_traveler]

RV appliance electrical consumption

and this from RV education 101, discusses your converter and battery charger electrical draw.

I hope that helps you make your decision between the 3 or 4 low noise level gensets sold today; which IMO are Honda, Yamaha, Boliy, and Generac.

Personally I've owned and used a Boliy 3600SI since 2008. It has better specs than any other genset of the same size.

 

 

I looked up the Boliy 3600SI very impressive. How is the quality and noise level compared to the Honda?

[Yarome]

It's also important to be aware that most contractor style generators do not come equipped with spark arrestors which makes them illegal to use in many areas "as is".

[markandkim]

It's also important to be aware that most contractor style generators do not come equipped with spark arrestors which makes them illegal to use in many areas "as is".

Champion does come with a spark arrestor.

[Kirk W]

I would like to buy a generator that can handle both the A/C and Micro not at the same time.

Have you considered one of the generators which can be purchased in a pair and run two in parallel, or one single when only one is needed? I think that might be your best choice and there are several.

 

Yamaha parallel pair Honda parallel pair Champion parallel pair

[Ray,IN]

 

 

I looked up the Boliy 3600SI very impressive. How is the quality and noise level compared to the Honda?

Mine was bought in August 2008. Since then I've changed the fuel filter and spark plug 2X. I bought an installed a new carb in 2011, which was totally my fault for failing to use Stabil in the gas, leaving gas in the carb for 6 months while we were traveling to AK and back, then touring the NW for a few months. The new carb was $39 from that website. FWIW, all electronics are plug N play, no expert required to replace things. There are no local dealers, but anyplace that works on Honda gensets can also work on a Boliy because they are very similarly built. They even have a free download of the complete service manual for owners.

Quality is IMO good except for the pigmented plastic case, it faded the 2nd year to a light dull red. I never shaded or shielded it from weather while in-use camping or use at home. Noise level is as advertised IMO.

The only genset I had to compare it to was my Coleman construction genset, which was perhaps 3x as loud, even with the optional $120 Briggs & Stratton "quiet muffler". I think most of the irritating noise came from the generator part and mechanical noise of the engine which cannot be quieted to the level of RVing gensets.

[Phil Saran]

You've been given lots of good advice on what type of generator to purchase, but the big question is where are you going to

put it to transport it??

 

If you are going to mount it on the rear of the TT then something like a Honda 3000 generator is great and will cover everything

you want to run.

 

If like me you have a bad back and your going to carry the generator in the bed of your truck I would look at the Honda 2000i

and it's mate. Wired together they put out 4000 watts of power.

 

The Honda 2000i weights in at about 34 lbs. and the Honda 3000 weights in at about 128 lbs.

 

When I owned travel trailers (2) and a cab over camper I used two Honda 2000i running in parallel.

[Ray,IN]

You've been given lots of good advice on what type of generator to purchase, but the big question is where are you going to

put it to transport it??

 

If you are going to mount it on the rear of the TT then something like a Honda 3000 generator is great and will cover everything

you want to run.

 

If like me you have a bad back and your going to carry the generator in the bed of your truck I would look at the Honda 2000i

and it's mate. Wired together they put out 4000 watts of power.

 

The Honda 2000i weights in at about 34 lbs. and the Honda 3000 weights in at about 128 lbs.

 

When I owned travel trailers (2) and a cab over camper I used two Honda 2000i running in parallel.

The Honda 2000 has a continuous output of 1,600 watts, so two coupled together has a maximum continuous output of 3,200 watts. The advertised 2,000 watts is instantaneous/start-up only.

[Yarome]

No one asked for it, but just to clarify a few points on wattage ratings. There is NO industry standard on wattage ratings. It's up to the manufacturer to determine what defines the ratings. Some will list a 2000watt generator because that is the maximum output, but may only last for a fraction of a second. Some may use different standards like 10 second. Nearly ALL manufacturers sustained output which will range from 80%-90% of the maximum output. So no matter what brand you buy you'll never have sustained output listed on the device itself.

 

Let's make it more confusing. Not all manufacturers list, measure, or even use the same terminology with their output ratings. Ie., Honda and Yamaha portable inverters actually measure 3 ratings. Maximum, sustained, and commonly called iAVR. To them.. "maximum" is the maximum current sustainable for 30 minutes. So a 2000watt genny is 2000watts for 30 minutes.. NOT to be confused with "surge". iAVR is their "surge". The maximum output sustainable for 10 seconds. So in their case, their actual ratings would be 2300w/2000w/1600w.

 

That is, in part, why not all 2000watt generators are created equal and while some may run.. say.. an A/C unit.. while others will not. Ie., 2000watts for a fraction of a second won't kick over an A/C compressor, but 2300watts for 10 seconds will. Likewise, a generator putting out 2000watts for 30 minutes will "seemingly" handle much greater energy loads (what can be run at the same time) than a 2000watt generator that cannot put out more than 1600watts (sustained) for more than a fraction of a second.

 

When you're pushing heavy loads it is really very difficult to say precisely what "size" of generator is needed when they really are not created equal.

 

Muddy enough?

[Yarome]

The advertised 2,000 watts is instantaneous/start-up only.

 

As mentioned above, the Honda 2000 would have 2300w surge/start-up only (10 seconds), 2000w maximum for 30 minutes, and 1600w continuous. HOWEVER.. you can't simply double those figures when paralleling. In parallel mode the sync technology limits them to continuous mode only.. so 3200watts. Eco-mode will also not be available.