New electrical panel question

[buckeyefarmer]

Trying to figure out how much power (amps) one draws from your energy usage (bill) is like trying to figure out what your (maximum) speed was by using your odometer and a stop watch..

Power is Watts, Current is Amps.

but you are right, your load changes all the time. Your bill is your best guide for what you are using.

I wouldn't put in less than a 200A panel for a house, with lots of breaker space. I like to put in a lot more circuits than the minimum.

 

[dickfoster]

Power is Watts, Current is Amps.

but you are right, your load changes all the time. Your bill is your best guide for what you are using.

I wouldn't put in less than a 200A panel for a house, with lots of breaker space. I like to put in a lot more circuits than the minimum.

Nether would I. Heck if I could, I'd get more. Get as much as you can, while you can.

BTW I'm a retired EE, just so you know, but I wasn't going to get all into power factors and what not. LOL

 

[Qapla]

Seems to me the OP asked for opinions on 100a vs 200a service

So, completely renovating and adding on to a 1940s farm house. My question is, what size of service should I go for? 100amp or 200 amp?...

So, some of us getting by with 30a, 60a, or the like or needing 3 phase really has nothing to do with his question.

I know in our area, if you do any kind of initial build or replace a service the minimum you can now legally install is 100a - so discussing less than 100a would not even apply - this could be true of where he lives.

Now, as to the original question, if you are going to replace the drop and the panel, I'd go with 200a - makes adding any additional sub panels much easier. I would probably want a "pass-through" panel.

Some utility companies will give/install the meter base free of charge - I would ask! I did and they gave me what I needed even though I could but it at a DIY. They often do this because they know the meter base they hand out is an exact fit and gauged to fit their meters and power requirements.

Our power company also does not charge to upgrade the transformer or the drop from their transformer to the weather head. If underground, you have to provide the conduit, properly sized and buried to depth and they will provide the drop.

Make sure you know what you have to pay for and what they will provide before you decide what to do and work within you budget. Often they will let you pay for everything instead of volunteering that they will provide some of the materials unless you ask.

 

[techman]

For those not intimate with the subject, a clamp-on will tell you amps. If you multiply amps times volts, you usually do NOT get watts. What you will calculate is VA, or volt-amps. To find watts you must also know the power factor of the device or circuit. Watts=VA times PowerFactor. There are meters that will measure watts, often called a true wattmeter (FYI home electric meters, old disk types and newer solid state models, DO measure true watts). Home devices like Kill-A-Watt and the Energy Detective do measure true watts. Many people are fooled when they use a clamp-on and measure a lightly loaded electric motor and see that they think it is using 20-30% power with little load. In reality if power factor is taken in consideration the motor's load is low and close to what you would expect.

Home "energy saving" devices can help improve power factor a bit, but since residential consumers do not pay for VA or bad power factor (larger industrial users do pay for bad power factor), there is only a few penny's a year of savings.

paul

 

[2ndhalf]

OK. Please educate me on this. If I have a 100 Amp wire to the service entrance, and put in a 200 Amp panel, but change out the main breaker to be a 100 Amp breaker, what is wrong with that?

I know I have to upgrade the main feed wire to put the 200 Amp breaker back in, but if I ever need the 200 Amps, I don't have to change out the panel. And, I get a lot more breaker slots. As people have said, with LED lights and more efficient appliances, real amperage draws are decreasing, but the number of circuits desired seems to be increasing.

Nothing wrong with what you descibe as long as the main matches the wire to the service entrance.

 

[2ndhalf]

If you're changing the service to underground anyway it's a no brainer to go with the 200A service if not more if you can get it. Heck, I wish they'd run 3 phase so I could run 3 phase motors easy.

Agree, given that info.. go with 200 amp and don't give it a second thought.

 

[Zerk]

I think some people are getting past the subject.

Talk to an electrician ask for a quote on 100 amp service and 200, see what it comes in as. Think about what your need are. Will you be running a 3 phase ________? Do you think you will be putting in a bunch of big motors, and have your buddies over running them the same time?

Talk to your utility about meter charges, and see what makes a difference.

Sure somethings help when selling a house. But doesn't mean it hurts if you don't have them. Lots of things go into the buying deciscion of a home. I doubt they will go screaming away if you have 100 service, then may not even know what a 200 is.

 

[Zerk]

How many people need 3phase motors, or have desire to have one?

The chance that you will need 3 phase service is about 1%, if that.

 

[teejk]

How many people need 3phase motors, or have desire to have one?

The chance that you will need 3 phase service is about 1%, if that.

On used woodworking equipment there are some great deals on well-maintained 3ph equipment (mostly from school shops). I guess the phase converters have gotten cheaper and more reliable to let them run on 240v single phase so the costs of installing 3ph doesn't make sense to me.

 

[Zerk]

On used woodworking equipment there are some great deals on well-maintained 3ph equipment (mostly from school shops). I guess the phase converters have gotten cheaper and more reliable to let them run on 240v single phase so the costs of installing 3ph doesn't make sense to me.

Yes I have heard you can get 3 phase machinary cheap at times, since it can be hard to sell.

But has anyone asked him if he plans on having some big *** machines, or if he even have room on the property to put a shop? What does 3 phase service cost?