Another Electric circuit posting

[ivseenbetter]

I didn't want to hijack Gweedo's post but after reading his thread it made me start thinking about some things.

I have all of my equipment plugged into a couple of outlets in my closet. However, I am pretty sure they are all on the same circuit. So far no issues. However, do I need to be concerned about having it all on a "dedicated circuit"?

What does it take to overload the circuit?

 

[10010011]

I didn't want to hijack Gweedo's post but after reading his thread it made me start thinking about some things.

I have all of my equipment plugged into a couple of outlets in my closet. However, I am pretty sure they are all on the same circuit. So far no issues. However, do I need to be concerned about having it all on a "dedicated circuit"?

What does it take to overload the circuit?

Well if you are not tripping a breaker then you are not overloading your circuit.

Personally I don't buy the whole dedicated circuit thing.

It's not like the noise generated by say your refrigerator is going to magically stop at the breaker panel.

Is it somehow confused on what branch circuit to take, then just give up and go to ground?

If this was so them why doesn't all the electrical noise present on the AC lines stop at the breaker panel?

 

[Rickster71]

If you haven't had any tripped breakers or noise so far. It sounds like you're ok.
The breaker will trip if, and when you exceeded it's ampacity. Probably 15amps if it's residential.

Though when a noise, or ampacity problem pops up, a dedicated circuit can help.
A typical equipment grounding conductor can go through a dozen or more poor splices and connections before it gets back to the building's grounding system. A dedicated circuit would resolve that type of problem.

The standard electrical grounding system throughout a building isn't designed to have current constantly flowing through it--and yet it does, you cannot stop it. The reason a ground will not and never be perfectly noise free is that the grounding electrode conductor is nothing more than a long wire from point A to point B. And the longer the wire the more noise it will pick up. If you have electricity you will have electromagnetic lines cutting through the air and anytime one of the lines cross any conductor in the ground system; it will produce an unwanted voltage. Those voltages cause noise, and are looking for the path of least resistance back to ground.

 

[Tarub]

This is when people makes a lot of mistakes all the time. When the circuit breaker keeps on tripping, they replace it with the higher amperage.....TADA, no more tripiing of the circuit breaker! This is a big NO NO! Yes, the new 30 amps circuit breaker you just put in will not trip on an overload circuit. But the 14 gauge wiring on your old house cant handle all the amperage and will heat up. This is the cause of fire on a lot houses. So make sure your circuit breaker amperage match with the wirings as per National Electrical Code.

Sometimes if you have a old fluorescent lighting on the same circuit, this might cause some electrical noise. The old fluorescent lighting uses a magnetic ballast. That is why you hear those humming when your turn on the lights. Nowadays they use the electronic ballast which eliminates noise and humming specially use on computer rooms.

 

[Rickster71]

I forgot these earlier:

Common Mode Noise-This is noise that exists between the power conductors, hot and neutral, with respect to the ground conductor.



Normal mode noise - This is noise that exists between the power (hot) wire and neutral conductor.



RFI - This is radio frequency interference.




EMI - This is electromagnetic coupling between conductors.


Inter system ground noise - Inter system ground noise can exist between the ground wires supplying interconnected devices.

 

[domiereavron]

Just a few points of interest, all outlets in a kitchen should be a seperate breaker. So a fridge should not be hooked up to anything else on a circuit. Generally, you can only have 12 outlets/lights on a breaker. This is using old standards before energy efficient bulbs and other appliances. I cant see how anyone could blow a circuit unless the house was wired badly.

 

[mtrycrafts]

...
Is it somehow confused on what branch circuit to take, then just give up and go to ground?

If this was so them why doesn't all the electrical noise present on the AC lines stop at the breaker panel?

Simple. Some noise are smarter than the others. Especially the ones who come in from the outside. They have more time to become smarter

 

[mtrycrafts]

Just a few points of interest, all outlets in a kitchen should be a seperate breaker. So a fridge should not be hooked up to anything else on a circuit. .

I don't think that is totally accurate. Large appliances do have their individual circuits by code: fridge, garbage disposer, compactor, dishwasher, etc. But, you only need a minimum of two 20A circuits for wall outlets in the kitchen. I have 5 or 6 such circuits

 

[Rickster71]

Just a few points of interest, all outlets in a kitchen should be a seperate breaker. So a fridge should not be hooked up to anything else on a circuit.

Much of this is dependant on the age of the home.

Generally, you can only have 12 outlets/lights on a breaker. This is using old standards before energy efficient bulbs and other appliances. I cant see how anyone could blow a circuit unless the house was wired badly.

There is nothing in the NEC that mentions the number of outlets per circuit.
It is calculated, 3 volt-amps per sq foot, for residential general lighting, and receptacle loads.
This doesn't include kitchen or laundry room calculations.

 

[mtrycrafts]

...There is nothing in the NEC that mentions the number of outlets per circuit.
It is calculated, 3 volt-amps per sq foot, for residential general lighting, and receptacle loads.
This doesn't include kitchen or laundry room calculations.

And, code requires at least one 20A circuit for dining room and living/family rooms, although they can be one circuit available to those.

 

[Rickster71]

And, code requires at least one 20A circuit for dining room and living/family rooms, although they can be one circuit available to those.

I wish the NEC required the same for bedrooms. These days a bedroom could have TV's, computer, a stereo, hair dryer, all on a shared circuit with other rooms.
Yes, the 2008 NEC 210.12 requires the dinning room circuits to be AFCI protected, where as the kitchen circuits do not need AFCI protection.(Arc fault Breakers) So, you probably would want to run a separate dedicated 20A circuit for the dinning room receptacles to avoid possible problems with false tripping.
There were so many nuisance tripping problems with AFCI's the state of NJ opted out of that part of the code.

 

[domiereavron]

That is just the general rule of thumb I use. 12 outlets per circuit. Dedicated 20 amp circuits for each load in the kitchen. Dedicated circuits with anything with a motor, 6 feet distance to each recep. except in hallways and threeway switches at the entry and exit of every room and hallway. That is my philosphy

 

[mtrycrafts]

I wish the NEC required the same for bedrooms. These days a bedroom could have TV's, computer, a stereo, hair dryer, all on a shared circuit with other rooms.
.

Hair dryers are in bathrooms and it requires a 20A circuit if I remember correctly. I have a dedicated wall mounted one in 3 baths
So, a bedroom, could easily handle a TV, around 150watts to 500 watts, computer being about 150 watts. But, I doubt you are prevented from using 20A in bedrooms. You just have to build it yourself.
Interesting that NJ would opt out of that part.

 

[mtrycrafts]

That is just the general rule of thumb I use. 12 outlets per circuit. Dedicated 20 amp circuits for each load in the kitchen. Dedicated circuits with anything with a motor, 6 feet distance to each recep. except in hallways and threeway switches at the entry and exit of every room and hallway. That is my philosphy

That's a good philosophy

 

[Rickster71]

Hair dryers are in bathrooms and it requires a 20A circuit if I remember correctly.

My neighbor has a wife, and 4 daughters. When they all get ready to go out at the same time,
It's not pretty; hairdryers any place there's a mirror.

Interesting that NJ would opt out of that part.

AFCI protection.(Arc fault Breakers) are nice in theory. NJ did have it for a short, but the nuisance trips, and call backs got really out of hand.
For example, people would unplug their vacuum while it was still on, and it would trip the breaker.

 

[mtrycrafts]

....people would unplug their vacuum while it was still on, and it would trip the breaker.

That will teach them to use the switch

Are those different from the GFCI types?

 

[BMXTRIX]

The rule as I know it is that when you are looking at a 20amp circuit the maximum load can be 1920 watts continuous. For a 15amp circuit it is 1440 watts continuous. With 12 gauge and 14 gauge wiring respectively.

The hard part I think is that while you don't need a dedicated outlet for your gear, you do need to consider (and find) everything else which may be on that circuit. You could be wired to lights, or other devices, and I sure as heck have wiring in my house that hits bedrooms, my office, and other locations, almost at random. One outlet in a room may not be on the same circuit as another, but may tie into outlets in different rooms.

But, AFAIK, there is nothing against using 20amp circuts or 15amp circuits within a home as long as the proper gauge wiring is used. As such, when my home was built, the electricians had no issue at all running a dedicated 20amp circuit from the box to my eqipment rack location in the basement.

If I had it to do over again, I would of had them run two more 20amp circuits for my basement, which is unfinished, but I put a lot of lighting in and now when I turn on power tools, the lights flicker.

Anyone have any solutions for interference that rolls up a TV, like a ground loop, when you turn on dimmers... even after the ground is lifted from the TV?

 

[ivseenbetter]

Wow, you all know a ton more about electricity than I will every be able to grasp. I guess for now, it is working so I shouldn't complain. My main concern though is that I still have to plug in my MFW 15s when I get them...and I think the plugs I will be using are on the same circuit as the other equipment. Hopefully they don't push it over the limit.

 

[Rickster71]

Anyone have any solutions for interference that rolls up a TV, like a ground loop, when you turn on dimmers... even after the ground is lifted from the TV?

Sounds like Radio Frequency Interference (RFI) from the dimmer. What brand dimmer, and how old are they?
Also, what type of lighting?

Most better, brand dimmers have RFI suppression circuitry. Don't go cheap, when it comes to dimmers.
Some manufacturers can supply additional filtering.

Off the top of my head, the first things I check are: Swap out the dimmer with a switch, just to see if the problem goes away.
Just to verify it's RFI or a ground loop.

Put dimmer on a separate circuit, from the TV or audio equipment.

Check all the ground and neutral connections.

Run dimmer wiring in its own metal conduit.

 

[Rickster71]

Are those different from the GFCI types?

GFI's protect against electrical shock.

Whereas AFI breakers actually monitor a certain waveform pattern that is characterized by a steady, relatively low-level, high-frequency current waveform. When an AFI detects that pattern, they recognize this signature as being an arc fault.

An arc fault can begin with the smallest of damage to conductor insulation. At first, an imperceptible current flows through that weak link from one conductor to another. The resultant current is relatively small, often much too small to trip a conventional breaker. Over time, further damage develops as the insulation is heated by the arc. Eventually, the damage becomes significant enough to allow a more intense arc and to ultimately cause a fire. An Arc Fault breaker would trip in the earliest stages of this scenario.

So far they sound great so far, but.

When they first came into use, a problem that cropped up involved the normal arcing in electrical circuits. Like the arc that is seen when pulling out an electrical cord or the arc a light switch makes when it is operated. Power tools are another example, as power tools generate a sustained arc while being operated.

Though they are better now, from what I hear.