Author Topic: Determining what kind of generator I need...  (Read 8775 times)

0 Members and 1 Guest are viewing this topic.

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Determining what kind of generator I need...
« on: May 05, 2014, 04:34:13 PM »
After much consideration, I think my main power needs would be during the build of my cabin, more so than once the cabin is built.  Once complete, I plan on using propane for almost everything, and simply have a generator to top up any batteries, maybe run a pump in the morning or minor electrics.  During the build, I need something I can transport back and forth, something that I can lift by myself (I have 3 herniated discs in my lower back so am limited here) and what can fit in the trunk of my economy sized car.  I am considering a small 2000 watt inverter with a cost of around $600.  I know I can get much more power for less money if I go with a standard generator, but it will weigh too much and be too difficult to transport in my small car.

With this in mind, I am looking for power tools that do not take a lot of power.  Most of what I have is 15A saws.  I need a new circular saw and found a very nice Makita 10.5 A circular saw going for ~$100, (almost 50% off the list price).  I was wondering if anyone was in a similar situation, and if they regretted the smaller powered inverter, and/or having a lower amperage saw? 

My best friend thinks I need to save about $1200 and go with a stationary diesel generator to get 14 kW power.  He likes his TV and electronic gadgets... I figured a few lights and absolute worse case a small pump to fill a holding tank now and then, can't require that much power. 

Offline hpinson

  • Administrator
  • Senior Member
  • *****
  • Posts: 849
Re: Determining what kind of generator I need...
« Reply #1 on: May 05, 2014, 05:01:04 PM »
I've been keeping tools under 13.5 Amps and have had no problems using the Honda eu2000i, running one tool at a time. 15 amps is going to be a problem, at least on startup and when under load. I do not regret going for the smaller genset. It does require some adaptation in work habits. I think quite a few on this board will agree.

I will bring it places I would never think of bringing a bigger/ heavier generator.

The decent clones, like the Champion make it even more attractive, at their lower prices.

And it is nice and quiet.

Offline MountainDon

  • Administrator
  • Journeyman
  • *****
  • Posts: 16,813
  • Jemez Mountains, NM; that's pronounced HEY-mess
    • My 15.75 x 30 Jemez Cabin
Re: Determining what kind of generator I need...
« Reply #2 on: May 05, 2014, 06:06:07 PM »
I do not like most generators. Most are too noisy.

We have a Yamaha EF2800i and a Honda EU2000i.  The Yamaha has just under 1200 hours on it. I think we bought it in 2004 or so. The Honda is new; has less than a handful of hours so far. It is much quieter than the old 2800 Yamaha, which is much quieter than the typical box store generator. I selected the Honda 2000i over the yamaha 2000i version mainly for the difference in physical dimensions. The storage place for the new generator is in a trailer and the one inch less height of the Honda tipped the choice in that direction.

I have seen a number of favorable reviews, happy owners of the Champion inverter series brand. There are a lot of threads on various inverter generator brands over on rv.net forum. The general consensus there has been that the Champion inverters are better than any of the other alternatives to Honda and Yamaha. As for me I was not ready to make the jump from the Honda and Yamaha. I paid 999 delivered; more than a Champion but it pleases me.


One thing I would like for a generator at the cabin is an electric start. My wife can not start the ones with a recoil starter. But electric start would mean a 3000 watt H or Y at much higher price. Maybe someday when I am older and less able as well.

Also for something like an electric start at the cabin I would consider getting a propane kit. Then there is never a concern about the liquid fuel going bad, no gummed up carbs. The oil change interval can be stretched out as well. Propane conversion will derate the output some, but I'm not sure by how much as that is also altitude dependent, but I am certain either 3000 would work for us.
Just because something has been done and has not failed, doesn’t mean it is good design.

Offline flyingvan

  • Journeyman
  • *****
  • Posts: 1,022
  • Welcome to the CP-Forum
    • flyingvan
Re: Determining what kind of generator I need...
« Reply #3 on: May 06, 2014, 05:25:07 AM »
Really good article on sizing a generator.

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=5&ved=0CEQQFjAE&url=http%3A%2F%2Fwww.homepower.com%2Fsites%2Fdefault%2Ffiles%2Fuploads%2Fwebextras%2FHP138_pg88_Goodnight.pdf&ei=shNTUrbLEOegiQKn7IGwCQ&usg=AFQjCNF4WOWSIrQXyL9F8qARVGMdrlQXjg&bvm=bv.53537100,d.cGE

  Takes temperature, altitude, surge factor, and power factor into account.

In a nutshell---If you add up the wattage required for everything you might want to run for continuous use (as opposed to surge) and start from there... Here's what I calculated for Cuyamaca Cottage

Continuous watts needed-------------2,380
   / power factor adjustment                 .85    (explained in the article)
   / altitude derating                            .825     (3.5% per 1000' above sea level)
   / temperature derating                      .97     (1% per 10 degrees above 60F--worst case scenario here)
   X surge rating                                   1.2      (120%.  She'd have to run the disposal just when the fridge kicks on)

   means I need a generator with a peak power of just under 4,200 watts.  Using LPG mine's rated at 5850 so there's a bit of padding there.
    The article talks about charging batteries simultaneously.  Not an issue for me just yet, but I like the idea of a discretionary load that is used while demand is low.  Also talks about autotransformers to balance uneven loads so you don't demand too much from one leg of the generator.
     Aside from initial investment costs, there is an efficiency advantage to using the smallest generator you can get by with.  It takes a 4,000 watt generator less fuel to generate 3,000 watts than for a 20,000 watt generator to produce 3,000 watts

     THis is where I got my data for sizing my generator.  Some great info in that article.  The surge ratings for the clear sine wave (inverter) generators is usually far less than the old style generators
Find what you love and let it kill you.

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #4 on: May 06, 2014, 01:26:55 PM »
Interesting article, I will sit down and do some more concrete calculations with this info.  Efficiency is definitely important to me, as much as being able to actually move the generator and store it or transport it.  The smaller the better in my eyes, as long as it meets the needs the cost should be secondary.  That said if I am going to pay a lot, I want a good quality machine that will last for many years to come.

I was originally looking at this Champion 2000W inverter ($599.99). 
http://www.canadiantire.ca/en/pdp/champion-2000w-inverter-generator-0550329p.html

Then I came across this slightly cheaper Powerhouse PH2100PRi Inverter Generator with a Remote Starter $539.99
http://www.costco.ca/Powerhouse%C2%AE-PH2100PRi-Inverter-Generator-with-Remote-Starter.product.100109382.html

I like the idea of the remote starter.  Waking up in the morning and pressing a button rather than tramping through the wet grass to pull start. I guess you are sacrificing some quality over convenience though. Still, brewing a nice cup of coffee with warm feet is hard to argue with.

And eventually some small solar power kit like this:
http://www.homedepot.ca/product/400-watt-off-grid-solar-panel-kit/823975

For just myself, I don't think I need any power at all... the cabin will be very tiny and used not very much to require showers and such.  That said, I do have a 4 year old so the possibility of having that generator to power maybe a small TV and DVD player, or portable DVD and just charge batteries will probably be priceless to keep her happy.  I would also like some 12V LED lighting throughout the cabin, so if I have a generator I can throw in a few 110V lights here and there for when company comes over.

* I have been discussing the land situation with my buddy and his father. 
They used to own a much larger lot years back (just down the road from where they are now).  They are now considering buying that lot back, and since I am so eager to get some land, if they do buy it then they will cut off a chunk for me sized for the the price I have to spend. (That probably means around $1k per acre, so a 5 acre spot in some corner of the bigger lot).  Works for me, I think there is a $1000 lawyer fee for splitting the land and doing the divisions, which I would be responsible for.  If that is the only way I can get this ball rolling then so be it.  :)  There is a major advantage of being next to my buddy's land, his Dad owns a tractor (and some attachments for mowing and soon for digging), as well as two bulldozers, which need work but they are 1/2 way working.  They are kind of messy people though, and tend to keep old cars and trailers laying about the land.  That said if there is a wooded part, I will ask for that so I can have some privacy and not have to look at the mess.  They tend to like more open areas anyways, and like to keep bees so I don't think they would mind me taking a wooded portion.  We'll see if that pans out... I am not sure when they are planning on buying, maybe this summer if not next.  I have to get cracking on my plans to ask the city if they approve before I spend money on the land.

Offline suburbancowboy

  • Senior Member
  • ****
  • Posts: 266
Re: Determining what kind of generator I need...
« Reply #5 on: May 06, 2014, 02:05:39 PM »
If you are going to run a larger air compressor to run tools, double check the amps rating.  I bought three generators during my build because my aircompressor kept throwing the breakers on them.  I ended up with a honda3000w genny.  It works great.  I also have a 6000W monster but it is way to loud and uses to much fuel.

My preference is to use ryobi battery powered tools that I charge at home and haul up to the cabin.  I have 8 of them.  Then I don't need the genny at all.  By the time I use up all the juice I am to tired anyway and rest or head back home.

My next genny purchase will be the honda2000.  Quiet and a fuel sipper.  Most of my building is done now.

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #6 on: May 06, 2014, 02:12:49 PM »
I tried to go the battery route about 20 years ago at my friends cottage.  We needed to add some structural support to the roof, and I went out and bought a full Ryobi 18V kit with circular saw, reciprocating saw, driver and flashlight.  Once we got up there, I made it through 1 5/8 sheet of plywood (literally 1 cut) and the battery was dead.  I had a backup, managed to cut a few dimensional lumber pieces and it died within no time as well.  That entire kit was useless after only 1 year, the batteries would no longer hold their charge.  Reading some reviews it seems their newer series (the + batteries and tools) are much better, but unfortunately incompatible with my old equipment.  And with each battery costing around $100, for the same price I think I will go for the genny route this time.

I just ordered my Makita 10.5A circular saw in preparation... :) 

Offline MountainDon

  • Administrator
  • Journeyman
  • *****
  • Posts: 16,813
  • Jemez Mountains, NM; that's pronounced HEY-mess
    • My 15.75 x 30 Jemez Cabin
Re: Determining what kind of generator I need...
« Reply #7 on: May 06, 2014, 03:15:20 PM »
Todays Lithium Ion batteries are so superior to the old Nicads there is really no comparison.  I built most of our cabin using a 18v Ryobi circular saw, regular drill, 90 degree angle drive drill and impact drill, reciprocating saw and saber/jig saw. Four batteries and two chargers with the chargers running off a small inverter on the truck battery mostly.

The generator was used to power the air compressor and the miter saw as well as recharge the RV 4 x 6 volt battery system and the microwave. Mostly the generator was not running very long. I had an auxiliary 20 gallon air tank from an old defunct compressor to give me more cu ft of air storage. I could air nail a long time with the generator off, then take a break and run the gen as needed.
Just because something has been done and has not failed, doesn’t mean it is good design.

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #8 on: May 06, 2014, 04:16:44 PM »
I have Dewalt battery powered drill that has outlasted 3 Mastercraft drills combined.  I know if the quality is there, the tool will last.  Drills, especially impact wrenches, I find can last a long time but something like a saw takes so much power that sometimes electric is the way to go.  If I will eventually want a small inverter anyways, might as well get it for the build and use it as much as I can.  Not sure what the Powerhouse quality is like, will need to research.  If the land comes up this year, I will wait on the generator, but if the land will only be purchased next summer I may go ahead and get the inverter this year.  One website I found shows that a fridge takes around 600 watts (probably not all equal, and not the start up power), but if I could run a fridge with the 2000 watt inverter then it could help us at home for power outages as well.  We have a wood burning fireplace (needs to be inspected), so heat should be OK if we huddle in the basement (slow burning stove).  It is just the food going bad we would need to consider.  And, doing it this way would make it a "house necessity" and not a "Adam wants more tools for his cabin ideas" tool.  Takes some of the pressure off of me.  :)

Is it just me or do the prices skyrocket with any inverter over 2000 watts?  Jump to 3000 watts and it doubles-triples in price.  What gives?

Offline hpinson

  • Administrator
  • Senior Member
  • *****
  • Posts: 849
Re: Determining what kind of generator I need...
« Reply #9 on: May 06, 2014, 04:33:44 PM »
So what would you run with the generator?  There are a few things that might require more, rather than less:

-- A mid size or large air conditioner

-- 15 AMP tools

-- A bigger air compressor

-- A deep well pump

-- An electric refrigerator

-- A washing machine

-- An electric cloths dryer

-- A big LCD TV or monitor

-- Electric pipe defrost wrap

-- Electric heaters

What else?

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #10 on: May 06, 2014, 05:44:18 PM »
For the build:

I will now have a 10.5 A circular saw.  I may need to purchase a smaller amperage table saw, but maybe I can get away with just the circular saw.
I will likely use ring shank nails, and/or construction screws with my Dewalt battery drill (so charger mainly).
If I use a compressor, mine is a 8 gallon 12.5 A one, not sure if the surge would surpass the 2000W inverter maximum.
All of my smaller tools, like the jigsaw and sanders are in the 6-8 amp range.

For cabin use:

Fridge, stove, some lights, possibly a heater, will be all propane.  One idea was to actually find an old camper trailer, use it during the build, then gut out the propane appliances to install in the cabin and use the empty trailer as storage.
There will not be any air conditioning, clothes washer or dryer, and if it can be avoided no TV or even radio.  (I like my peace and quiet).
The cabin will be summer only use, and not have any real plumbing to speak of so no need for any pipe defrost mechanisms.  I will probably have a chemical toilet, and if no agency is watching I might go with a home-made septic system, but we are talking 1-2 person use, 1 day on the weekend, every 2-3 weekend, in the summer only.  It would take 20 years to fill a 50 gallon drum.

The pump is the real question.  It really depends on the land.  If I can find something with a stream or brook, I would like to use a small pump to draw water to a holding tank.  This would be used primarily for washing up, and possible for a toilet at some point.  I do not know pumps, but even if the power was higher that my inverter could handle, I would consider a gas powered pump since it would only need filling periodically.

I would like to have LED lighting throughout the cabin.  My plan calls for a ladder of sorts to get to the loft.  With a young daughter, I want to make sure I can keep the steps light at night in case she decides to explore or needs to use the toilet without waking me up.  I can use a propane stove top kettle or coffee maker, but I can see potentially using the generator for a coffee maker.  If people come over, you may want brighter lights to keep things less dreary.  And for especially rainy days, I would consider a DVD player or something of the sort for the little one's amusement.  I think I can get away with just a couple of batteries worse case, so the inverter would serve more as frosting rather than necessity.  Any work that needs some I would rely on it as well. 

The cabin itself will be only 16'x16', so I think either a small wood stove, or a propane or kerosene burner would be enough for the colder spring or fall days. 

For home use:

This is where it becomes a bit of an issue.  My wife originally asked me to look into a generator because of power outages.  1 concern is food going bad, so I may want to run a fridge with the inverter to keep our food from spoiling.  Another concern is the pipes, and not letting them freeze.  Since the slow combustion wood stove is in the basement, I think I could just run a fan to the utility room from the stove to keep the temperatures above freezing.  We would have to be home to monitor this though. 

Offline MountainDon

  • Administrator
  • Journeyman
  • *****
  • Posts: 16,813
  • Jemez Mountains, NM; that's pronounced HEY-mess
    • My 15.75 x 30 Jemez Cabin
Re: Determining what kind of generator I need...
« Reply #11 on: May 06, 2014, 05:46:03 PM »
The H 2000 runs our fridge no problem. Also runs the gas furnace.

Most newer inverter generators can also use parallel cords to increase available power. Something to consider if higher power needs might occur at times.
Just because something has been done and has not failed, doesn’t mean it is good design.

Offline MountainDon

  • Administrator
  • Journeyman
  • *****
  • Posts: 16,813
  • Jemez Mountains, NM; that's pronounced HEY-mess
    • My 15.75 x 30 Jemez Cabin
Re: Determining what kind of generator I need...
« Reply #12 on: May 06, 2014, 05:51:27 PM »
The H 2000 is only useful to us at home if we are there. If we are away for a few days that could be a problem. On the plus side though is in our location power outages have usually been measured in single digit hours. That's since '85 and most outages were back when we were living on the outside edge of a rapidly developing area. Contractors seemed to misread the power line marking or something.
Just because something has been done and has not failed, doesn’t mean it is good design.

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #13 on: May 06, 2014, 05:54:57 PM »
Does a fridge really need to be powered non stop in the case of a power outage?  My thinking is that you could probably cycle 2 hours on, 2 hours off, without it warming up enough to spoil your food (which would prolong your generator gas usage).

Offline MountainDon

  • Administrator
  • Journeyman
  • *****
  • Posts: 16,813
  • Jemez Mountains, NM; that's pronounced HEY-mess
    • My 15.75 x 30 Jemez Cabin
Re: Determining what kind of generator I need...
« Reply #14 on: May 06, 2014, 06:04:08 PM »
I think time rotation is fine. Most of the time I never worried unless the time out was approaching a half day. If the power is out open the door as little as possible. It's also handy to have a remote read thermometer sensor inside the fridge so temperature can be monitored with the doors closed.

Just because something has been done and has not failed, doesn’t mean it is good design.

Offline flyingvan

  • Journeyman
  • *****
  • Posts: 1,022
  • Welcome to the CP-Forum
    • flyingvan
Re: Determining what kind of generator I need...
« Reply #15 on: May 06, 2014, 06:16:51 PM »
We keep our freezer full all the time.  I've got a few milk jugs about 80% full of water that get stuck in there to fill any voids.  If we have a bunch of food the frozen jug gets moved to the fridge side.   When the power goes out a full fridge will keep food from spoiling much quicker than an empty one...
If you're managing power in the winter, remember that a fridge is just a big resistance heater.  A 1500 watt fridge will put the same amount of heat into a room as a 1500 watt electric heater----even more if the food isn't cold yet
Find what you love and let it kill you.

Offline DaveOrr

  • Senior Member
  • ****
  • Posts: 238
  • Living In The Land Of The Midnight Sun
    • The Arctic Angler
Re: Determining what kind of generator I need...
« Reply #16 on: May 06, 2014, 08:12:48 PM »
I will be starting work on my cabin this summer and just purchased a Yamaha EF2000IS inverter generator.
Got a good price on it through this company: http://www.wisesales.com/
Got it for $989 no tax, free shipping and 2nd year of warranty free.   ;D
Dave's Arctic Cabin: www.anglersparadise.ca

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #17 on: May 11, 2014, 07:30:44 AM »
In an attempt to gather some extra funding to go towards my future generator/inverter, I decided to sell off some stuff I had laying around that I was not using.  So far this weekend, I sold a motorcycle cover for $25, and an old kayak for $160.  I also had a large bag of pennies and other random coins that had been sitting in a bag for years, brought them to the machine at the local grocery store.  That turned out to be 26.6 lbs of coins, 23 quarters, 448 dimes, 411 nickels and 3317 pennies for a total of $104.27... but they only paid out $91.86 because of their almost 12% fee!   :o  I was too lazy to roll all of that anyways.Along with a few extra bucks I had my fund is already up to $295!  Another weekend like this and I am ready to buy the inverter!  :)

So I have been comparing a few different models.  While I am not 100% sure that a 2000w is enough, the next step up is far too expensive, far too heavy and loud, and too not economical enough for my needs.  I was doing a comparison between the Champion and the Powerhouse.  They are quite similar, Champion is slightly quieter, but it uses a lot less gas.  They have very similar power ratings, but the Champion has an 80cc engine and gets 9.5 hours (1/4 power) out of 1 gallon of gas, where the powerhouse is a 125cc engine and only gets 8.2 hours (1/4 power) for 1.4 gallons of gas.  Price is very similar, the thing that might be nicer with the Powerhouse if the possibility of a remote starter.  Still, I think the Champion *might* be a better quality machine.  The Honda and Yamaha are nice machines but a little out of my budget.  I am still trying to convince my wife of the usefulness of the generator at home.  She sees the $600 price tag and freaks out... the Honda is $1200... twice the price, I won't even mention it to her.  Realistically, we can't heat the house with such a small generator but the fireplace is a slow combustion, just need to have it inspected. 

One question...  my deck in the back is about 3' off the ground, and has a covered roof.  There are cedars on the side that keep in the humidity and thus some of the planks have rotted.  I need to change some of them and was thinking I might build an insulated box under the deck (with a fan and exhaust for the muffler) and then have an access from on top of the deck.  I was thinking to keep the inverted stored in there for easy access when we need power.  Just run a couple of extension cords inside the house when needed.  It stays tucked away until needed, and regardless how much snow we have I can get to it since it is under a covered deck.  Would this be safe?  Would this be legal?  I would run a metal exhaust out of the box around the side of the house, and wire a fan so when it is running there is cool air being drawn over the engine.  Thoughts?  Is this a good idea?  Would it indeed make for a much quieter running machine?  (I thought a plywood box with safe n' sound lining it (or something similar)).

Offline flyingvan

  • Journeyman
  • *****
  • Posts: 1,022
  • Welcome to the CP-Forum
    • flyingvan
Re: Determining what kind of generator I need...
« Reply #18 on: May 11, 2014, 09:01:49 AM »
http://countryplans.com/smf/index.php?topic=13276.msg173070#msg173070    Here's what we ended up doing for the cottage.  Safe?  Probably.  Legal?  Depends.       The challenge is to make a housing that's theft proof, keeps sound in but lets heat out, allows for easy generator use in the worst weather, provides easy access for fueling and maintenance, and can't trap fumes.

Have you looked on Craigslist?  Lots of people buy generators in a panic then unload them at a discount.

I'm a fan of propane.  It won't go bad and the oil and engine life is extended.  Also a fan of the power transfer switch setup.

If you use a fan for cooling, set it up on a thermostat or switch or something so the generator isn't started under load (or you can just always leave the main breaker off until the unit gets up to speed)
Find what you love and let it kill you.

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #19 on: May 11, 2014, 11:10:49 AM »
The problem with a transfer switch is our heating is a 12000 BTU electric furnace.  I would need to switch only part of the power, which would mean rewiring part of the house so that the essential appliances are on a common circuit.  Not sure how feasible this will all be.  The "real" use case is for my eventual build or trailer power, but to sell it to the wife I need a viable solution.  Decisions decisions...  :)

Thanks for the input, nice thread.  That is actually where I got my ideas from.  You went without the inverter... does that mean a fridge and other main appliances can tolerate a generic generator?  Can you just purchase a small inverter (stand alone unit) to power your electronics if need be, thereby saving money?  So much to read still...

Offline flyingvan

  • Journeyman
  • *****
  • Posts: 1,022
  • Welcome to the CP-Forum
    • flyingvan
Re: Determining what kind of generator I need...
« Reply #20 on: May 11, 2014, 01:08:30 PM »
A friend who is an electrical engineer assures me the power from the generator is clean enough to power everything, even the DVD player and flat screen TV.  So far he's been right.  The range has a brain, so does the microwave.

Power transfer switches that can selsct only certain circuits are pretty common--here's one from Northern Tools https://www.google.com/shopping/product/2216369542018601624?q=Northern+Tools+power+transfer+switch&rls=com.microsoft:en-us:IE-SearchBox&prmd=ivns&sa=X&ei=gvRvU8W7LtLsoASO_YKgDg&ved=0CEcQ8wIwCA

A shortcut many people take is just going to the panel and shutting off the circuits you don't want to power.  I don't recommend that---For an emergency backup generator I think the simpler and more foolproof the better.....If you mounted it under your deck is there ANY chance of CO making it into the structure?
Find what you love and let it kill you.

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #21 on: April 16, 2015, 02:12:23 PM »
I know this is an old thread but...

What would happen if I used a 7 amp circular saw with a generator that could only supply 6.7 amps?
Would it just make the saw less powerful or could it damage the generator?

I have some wood to cut, my saw is a brand new Makita circular saw rated at 7 AMPs. 
The intended generator I want to use is a 1000 watt (800 watts continuous) and has a plaque on it that says its rated for 6.7 AMPS.
(Genmate GG950)
Here are some good pictures:
https://www.gcsurplus.ca/mn-eng.cfm?snc=wfsav&sc=ach-shop&vndsld=1&so=DESC&sf=ferm-clos&lci=&str=1&sr=1&ltnf=1&lcn=243490&lct=L


If it is just a matter of less power when under load, I can take my time... if it means damaging the generator then I may look for a different generator.

* EDIT *

I am getting senile in my old age.  The Makita is actually 10.5 AMPS as I read my first post.  Duhh... it's 7 1/2 inch... not amps.

Still, I wonder, if I had a Genny that was rated at 10 AMPS and I used a 10.5 AMP saw... same question?  More curiosity now cause the 6.7 will definitely not be enough for a 10.5 AMP saw.  :(


Offline MountainDon

  • Administrator
  • Journeyman
  • *****
  • Posts: 16,813
  • Jemez Mountains, NM; that's pronounced HEY-mess
    • My 15.75 x 30 Jemez Cabin
Re: Determining what kind of generator I need...
« Reply #22 on: April 16, 2015, 02:30:32 PM »
Generators like our Honda EU2000's have built in protection that will cut the power output well before there is any danger of the generator being damaged.  No idea about those.

The saw motor on the other hand, may run hotter if it can't get all the power it wants. IMO, it may be more likely that the saw may be damaged.   

Use a good sharp blade. A blade with fewer teeth is better than one with more teeth. Maybe a rougher cut but an easier cut.  More teeth = more cutting edges in contact with the wood when cutting. More cutting edges means more drag.

I see those are noisy little genny's.  ;D
Just because something has been done and has not failed, doesn’t mean it is good design.

Offline Adam Roby

  • Senior Member
  • ****
  • Posts: 647
  • Montreal, Canada
Re: Determining what kind of generator I need...
« Reply #23 on: April 16, 2015, 02:39:36 PM »
I see those are noisy little genny's.  ;D

Yeah, definitely not something you'd want to use at the campground. 
Our local CanadianTire has a Champion 1500 watt on sale right now for $199, which is pretty darn good in Canada (prices are quite a bit steeper here than in the USA).  Might consider that as an option instead...  although it only has a 10 amp breaker so will probably trip it constantly.
There is a local guy selling a used one 1850 watts for $125 (already negotiated down).  Might just wait it out until I really need it then make my decision at that moment in time.

Offline hpinson

  • Administrator
  • Senior Member
  • *****
  • Posts: 849
Re: Determining what kind of generator I need...
« Reply #24 on: April 16, 2015, 02:57:39 PM »
Amperage draw is highest when you start a cut. If you exceed what the generator can do, the generator will probably stall or be cut off by a governor. So if you are going to try - ease into cuts as much as you can.  I can't imagine this would do terribly much damage to the saw unless you made a habit of it.

Seconding the Champion 1500 inverter generator. It's is decent, quiet, and costs a lot less then a Honda eu2000i. I don't know if it has the longevity of a Honda eu2000i, but there are MANY positive reports around the Net (and a few negative ones too!).   I had one of the larger Champion non-invertor generators for awhile and was impressed by Champion phone tech support.  They walked me right through a repair phone to ear.

Costco often carries a decent Honda eu2000i clone and they have a great return policy if that store is available to you.

No regrets on getting the Honda though. Coupled with a good 12 or 13 Amp saw, it is a super practical setup for a build.




 

Templates: 5: index (default), Ads (default), Portal (default), Display (default), GenericControls (default).
Sub templates: 12: init, html_above, adsheaders_above, body_above, adsindex_above, portal_above, main, portal_below, adsindex_below, body_below, adsheaders_below, html_below.
Language files: 3: SPortal.english (default), index+Modifications.english (default), Ads.english (default).
Style sheets: 1: portal (default).
Files included: 38 - 1124KB. (show)
Cache hits: 16: 0.00237s for 40,804 bytes (show)
Queries used: 28.

[Show Queries]