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Pher9999

join:2011-07-06
Carmel, NY

Generator sizing Chart

»www.yamaha-motor.com/outdoor/gen···ing.aspx

using that link above, does the wattage seem right for sizing? we have a oil boiler and well, so trying to gauge for approiate size, I can count light bulbs. Propane stove, 2 fridges. I don't mind oversizing the generator, just don't want to waste too much money for never used.



alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1

Maybe I missed that part of the instructions, but...

For the ADDITIONAL STARTING WATTAGE REQUIREMENTS, you don't add up all of them. You only add the highest one in your list.

Also, you need two totals.
One total is the RUNNING wattage
The second total is the RUNNING wattage + (highest) starting wattage.

First total is for your generator's running wattage rating.
Second total is for your generator's starting wattage rating.

My generator is rated 3000W running, 4000W starting. So if the first total is 2000W and second total is 4000W, I am fine.


Pher9999

join:2011-07-06
Carmel, NY

But if the well pump and the Furnace need to spin up at the same time doesn't that use both starting wattages at the same time to double? so if both are around 2500w starting, I would need 5000w to get both up and runnning together?


garys_2k
Premium
join:2004-05-07
Farmington, MI

Sure, so a cushion to allow that to happen is an excellent idea. Beyond sizing for two motors that happen to spin up together, though, is likely overkill.



alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
reply to Pher9999

said by Pher9999:

But if the well pump and the Furnace need to spin up at the same time doesn't that use both starting wattages at the same time to double? so if both are around 2500w starting, I would need 5000w to get both up and runnning together?

It's possible, but very unlikely. We're talking about a couple of seconds of starting wattage per 15-20 minutes.

I'd suggest that you leave the furnace blower ON at all time, that way it will only kick start once.

Pher9999

join:2011-07-06
Carmel, NY

Furnace is boiler with radiator heat. no blower. circulator pump and the spark to light it.



alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1

1 recommendation

Then you'll need to deal with it.
But again, it's highly unlikely both would start at the same time.

If each of them kick start on average every 20 minutes, and they take 2 seconds to start:

20 minutes x 60 seconds = 1200 seconds
2 seconds / 1200 = 1/600th chance they start at the same time in a single 20 minute session. 600 attemps (in 20 minute spans) is 500 days



tmh

@verizon.net
reply to Pher9999

said by Pher9999:

»www.yamaha-motor.com/outdoor/gen···ing.aspx

using that link above, does the wattage seem right for sizing?

They look like typical values, your appliance's power draw may be different. For example, they have a fridge drawing 600W but mine only draws 300W.

The load requirements for an electric dryer look screwy. Running load is 5KW but additional starting load is 1.8KW. Everything else has a higher starting load than running load.

garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
·callwithus

said by tmh :

The load requirements for an electric dryer look screwy. Running load is 5KW but additional starting load is 1.8KW. Everything else has a higher starting load than running load.

Maybe the resistance heaters don't come on until after the motor is up to speed.

Pher9999

join:2011-07-06
Carmel, NY
reply to Pher9999

Plan is now to save towards standby Propane Generator with transfer switch. They don't want to deal with trying to manually start an engine in the dark.


nyrrule27

join:2007-12-06
Howell, NJ
reply to alkizmo

so i know amps X volts = watt. and if something is on a 15 amp breaker (correct me if im wrong) if it draws more then 15 amps it will pop, that its drawing less then 15 amps. so as a guide can you add up all the breakers in the panel and multiply by 120 volts that it would give you an aprox calculation on how many watt generator you would need. or is that a little too much.

Im not an electrician but sometimes come up with crazy ideas and theorys. this was just something i tought about when showering in the dark again..lol



Ken
Premium,MVM
join:2003-06-16
Markle, IN

said by nyrrule27:

so i know amps X volts = watt. and if something is on a 15 amp breaker (correct me if im wrong) if it draws more then 15 amps it will pop, that its drawing less then 15 amps. so as a guide can you add up all the breakers in the panel and multiply by 120 volts that it would give you an aprox calculation on how many watt generator you would need. or is that a little too much.

That's not a little too much, it's way way too much. I have a 15 amp breaker for nothing but my smoke alarms. Your calculation would add 15 amps in, but in reality that circuit draws a tiny fraction of that. Many of the circuits in your panel are like that, they never draw the full amount. Problem #2 is even though some of the circuits do draw the full amount, they don't all draw it at the same time.

scooper

join:2000-07-11
Youngsville, NC
kudos:2
reply to Pher9999

If you really want to get a good handle on how little watts a house really uses - get a TED 5000 , install it, and SEE what is really happening »www.theenergydetective.com/ . My house was originally built as all electric (and yes, I'm on a well too), and mostly still is (exceptions - propane furnace for backup and propane cooktop). I'm still using an electric tank water heater (pulls about 4.5 KW when running) and an electric clothes dryer, and my primary heating is a heatpump. The highest load I've ever pulled has been 25 KW - and that was also running the oven, a pool pump, and an electric tankless waterheater and the dishwasher (as well as those other loads) all at the same time. Normal running watts is about 2Kw in the winter (until the heatpump goes on - then its about 6KW startup - 4KW running). The water heater really doesn't come on very often (one reason why I'm still using electric instead of propane).



Coma
Thanks Steve
Premium
join:2001-12-30
NirvanaLand
reply to nyrrule27

said by nyrrule27:

if something is on a 15 amp breaker (correct me if im wrong) if it draws more then 15 amps it will pop . . .


I bought another rental house last year that has a Federal Pacific Electric Panel and their FPE Stab-Lok® breakers have well documented issues.

--
November is National Epilepsy Month


alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
reply to nyrrule27

said by nyrrule27:

so as a guide can you add up all the breakers in the panel and multiply by 120 volts that it would give you an aprox calculation on how many watt generator you would need. or is that a little too much.

WAAAAAYYYYY too much.

My panel is rated 100A (which is means 240v x 100A = 24kW)

If I added every single fuse's rating in there, I'd get 40kW.

Typical 120v receptacle/lighting circuits are rated 15A because that's the minimum possible, then you have multiple of those circuits in case you carry heavy load portable appliances around, like a vacuum cleaner. You can have 10 of those 15A circuits, it doesnt mean it's likely that you'll be using any more than 2 of those circuits at 50% of capacity at any given time.

For appliances like furnace, A/C, water heater, the ratings for their circuits are MAXIMUM protection, meaning if it goes above that rating, there's a problem, but most of the time, it's well UNDER that rating.

nyrrule27

join:2007-12-06
Howell, NJ

yea i figured it wasnt correct. like i said i get these crazy ideas. some make sense..some dont. i think the best way to figure out what i need is just to call someone in to calculate it.



alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1

1 edit

Double post, plz delete.



alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
reply to nyrrule27

said by nyrrule27:

yea i figured it wasnt correct. like i said i get these crazy ideas. some make sense..some dont. i think the best way to figure out what i need is just to call someone in to calculate it.

Actually if you're going to call an electrician to get the whole thing installed, may as well make them come for quotes, they'll do a calculation at the same time.

You can compare not only the quoted prices, but also see which wattage seems to come up more often. That way you will also get an average, in case you'd fall on an electrician that wanted to make a bigger profit by supplying you a generator bigger than your basic needs.

nyrrule27

join:2007-12-06
Howell, NJ

yea i would never jsut get one estimate. i would get a few. my cousins friend is a licenced electrician so he would prob give me the best price. he upgraded my servcie for me 2 years ago and did it alot cheaper then others.

There was another thing....would i call an electrician or a plummer. i guess i would need both but i would assume if i call an electrician they would have someone they use for these situations and vice versa.