USB Receptacle

[kwired]

I realized there was a sleep mode on my computer. It shuts everything off without having to re-boot when it's 'woke back up'.

I am now using sleep mode instead of running the computer 24/7. That should cut around 5 bucks off my electric bill.

Sleep mode usually powers down the display, shuts off disk drives, and maybe other peripheral devices, but still has processor powered up and ready to go, operation system is still running and RAM is in operation, any demand from system for powered down devices simply turns them back on and they are ready to go immediately.

System hibernate actually writes everything in memory to the disk, and then powers everything down, except for any "phantom" load that may be on the power supply that is also there when actually turned off but still plugged in. When you turn the system back on it simply reloads the memory with what was written to disk and you resume your session. Sometimes there are problems with resuming but that is the basic idea, and is especially handy for any system running on batteries to help lengthen run time on the batteries.

 

[GoldDigger]

Sleep mode usually powers down the display, shuts off disk drives, and maybe other peripheral devices, but still has processor powered up and ready to go, operation system is still running and RAM is in operation, any demand from system for powered down devices simply turns them back on and they are ready to go immediately.

System hibernate actually writes everything in memory to the disk, and then powers everything down, except for any "phantom" load that may be on the power supply that is also there when actually turned off but still plugged in. When you turn the system back on it simply reloads the memory with what was written to disk and you resume your session. Sometimes there are problems with resuming but that is the basic idea, and is especially handy for any system running on batteries to help lengthen run time on the batteries.

Some computers/operating systems, including Mac OS X for Mac Books, will prepare for both any time you select "sleep". As long as battery or other power remains available, the system will maintain the minimal power required to allow a fast return from sleep. But if that power runs out, the full state will already be saved to disk and a return from hibernate will be performed. That has the side effect that to actually hibernate you have to go to great lengths or actually disconnect all power including battery.

 

[mike1061]

Question for all, is one 15A-rated duplex receptacle permitted on a 20A branch circuit? Is it one or two receptacles?


IMO yes.

I do understand your opinion, but mine is different. The point of a single receptacle having the rating of the circuit is so that it is not overloaded. For example a single 15 amp receptacle is not allowed on a 20 amp branch circuit because the load could be 5 amps more than the rating. Yet more than one 15 amp receptacle is allowed on a 20 branch circuit because the load would be spread out. Also the likely hood of single appliance (or other corded device) exceeding the 15 amp rating of the receptacle unlikely. One instructor I had put it something like "If it's that big, it needs it's own circuit anyway".
Back to the rest of the point. That a duplex receptacle could easily have two separate appliances plugged into it. For example, a microwave and a fridge, or a microwave and a coffee machine, or a clothes washer and dryer. The combination of the two would not overload the branch circuit (wires or breaker) but could overload the duplex receptacle.
You know what I mean?
Thanks
Mike

 

[kwired]

I do understand your opinion, but mine is different. The point of a single receptacle having the rating of the circuit is so that it is not overloaded. For example a single 15 amp receptacle is not allowed on a 20 amp branch circuit because the load could be 5 amps more than the rating. Yet more than one 15 amp receptacle is allowed on a 20 branch circuit because the load would be spread out. Also the likely hood of single appliance (or other corded device) exceeding the 15 amp rating of the receptacle unlikely. One instructor I had put it something like "If it's that big, it needs it's own circuit anyway".
Back to the rest of the point. That a duplex receptacle could easily have two separate appliances plugged into it. For example, a microwave and a fridge, or a microwave and a coffee machine, or a clothes washer and dryer. The combination of the two would not overload the branch circuit (wires or breaker) but could overload the duplex receptacle.
You know what I mean?
Thanks
Mike

I think all 15 amp duplex receptacles available are designed for 20 amps they just don't accept a 20 amp cord cap.

You can supply one 15 amp duplex receptacle with a 20 amp circuit - it is considered two outlets in this case. You can supply multiple 15 amp receptacles on a 20 amp circuit and feed through each receptacle - they are designed for 20 amp feed thru.

 

[K8MHZ]

Sleep mode usually powers down the display, shuts off disk drives, and maybe other peripheral devices, but still has processor powered up and ready to go, operation system is still running and RAM is in operation, any demand from system for powered down devices simply turns them back on and they are ready to go immediately.

System hibernate actually writes everything in memory to the disk, and then powers everything down, except for any "phantom" load that may be on the power supply that is also there when actually turned off but still plugged in. When you turn the system back on it simply reloads the memory with what was written to disk and you resume your session. Sometimes there are problems with resuming but that is the basic idea, and is especially handy for any system running on batteries to help lengthen run time on the batteries.

When mine goes into sleep mode, it not only shuts down the monitor and disk drives, but all the fans as well, even the power supply and CPU fan. The only light that stays on is on the motherboard.

I really like the fact that when it's turned back on I don't have to wait for a re-boot. In 5 seconds I am right back to where I started.

So, why not employ a battery to supply the needs of sleep mode along with a flash drive = to RAM size that would copy RAM contents. Unless required for program installation or troubleshooting, a total re-boot would never be needed.

 

[kwired]

So, why not employ a battery to supply the needs of sleep mode along with a flash drive = to RAM size that would copy RAM contents. Unless required for program installation or troubleshooting, a total re-boot would never be needed.

I assume you are not running any version of Windows.

Windows always has something going on that maybe can be reset without rebooting, but is usually is just easier to reboot than to spend the time finding and fixing the problem(s).

 

[mike1061]

I think all 15 amp duplex receptacles available are designed for 20 amps they just don't accept a 20 amp cord cap.

You can supply one 15 amp duplex receptacle with a 20 amp circuit - it is considered two outlets in this case. You can supply multiple 15 amp receptacles on a 20 amp circuit and feed through each receptacle - they are designed for 20 amp feed thru.

I had no idea.
I'll see if I can find some more info about that. It changes things in my mind.
Thanks
Mike

 

[RustyShackleford]

... a single 15 amp receptacle is not allowed on a 20 amp branch circuit because the load could be 5 amps more than the rating. Yet more than one 15 amp receptacle is allowed on a 20 branch circuit because the load would be spread out.

This has always seemed very peculiar me. Generally, there is a strict requirement that every element of an X amp circuit (that is, a circuit protected by an X amp breaker) be rated for X amps. But in this one situation, the NEC says "hey, what the heck, it's cool, as long as there's more than one outlet on this 20amp circuit, there's no way some fool is going to plug a 20amp load into a single outlet". OTOH, running a 14ga switch-leg, which by construction can only be carrying current for the single load it's switching (typically a luminaire), is forbidden if it's on a 20amp circuit. I think it's more likely that someone will plug a 20amp load into some outlet on some 20amp circuit somewhere, other than one of the required single-outlet 20 amp circuits (e.g. washing machine), than is that someone is going to be controlling 20amps of lighting load from a single switch.

 

[tallgirl]

This has always seemed very peculiar me. Generally, there is a strict requirement that every element of an X amp circuit (that is, a circuit protected by an X amp breaker) be rated for X amps. But in this one situation, the NEC says "hey, what the heck, it's cool, as long as there's more than one outlet on this 20amp circuit, there's no way some fool is going to plug a 20amp load into a single outlet". OTOH, running a 14ga switch-leg, which by construction can only be carrying current for the single load it's switching (typically a luminaire), is forbidden if it's on a 20amp circuit. I think it's more likely that someone will plug a 20amp load into some outlet on some 20amp circuit somewhere, other than one of the required single-outlet 20 amp circuits (e.g. washing machine), than is that someone is going to be controlling 20amps of lighting load from a single switch.

The NEC is designed to prevent fires, not make sense. When I was writing software for marine engineers I had to implement some fairly bizarre rules. One day I asked and was told that every time a ship sinks, someone figures out what formula was responsible and changed it!

 

[GoldDigger]

One day I asked and was told that every time a ship sinks, someone figures out what formula was responsible and changed it!

And if they cannot figure out what caused the ship to sink, the pull a Boeing instead?

 

[kwired]

This has always seemed very peculiar me. Generally, there is a strict requirement that every element of an X amp circuit (that is, a circuit protected by an X amp breaker) be rated for X amps. But in this one situation, the NEC says "hey, what the heck, it's cool, as long as there's more than one outlet on this 20amp circuit, there's no way some fool is going to plug a 20amp load into a single outlet". OTOH, running a 14ga switch-leg, which by construction can only be carrying current for the single load it's switching (typically a luminaire), is forbidden if it's on a 20amp circuit. I think it's more likely that someone will plug a 20amp load into some outlet on some 20amp circuit somewhere, other than one of the required single-outlet 20 amp circuits (e.g. washing machine), than is that someone is going to be controlling 20amps of lighting load from a single switch.

The receptacles are designed to 20 amp standards AFAIK. The fact that they are 15 amp faces means you will not plug a 20 amp cord cap into them. If you plug a 20 amp load into them, then you have either cheated somehow or the load has the wrong cord cap installed.

The laundry circuit is not required to be a single 20 amp outlet. It is required to be supplied by a 20 amp circuit, but can have multiple outlets all in the laundry vicinity.

 

[mike1061]

The laundry circuit is not required to be a single 20 amp outlet. It is required to be supplied by a 20 amp circuit, but can have multiple outlets all in the laundry vicinity.

But it most often installed that way.
Thanks
Mike

 

[mike1061]

OTOH, running a 14ga switch-leg, which by construction can only be carrying current for the single load it's switching (typically a luminaire), is forbidden if it's on a 20amp circuit.

It is allowed as far as I know, under a tap conductor. It has to meet those rules, but that's not very hard.
Thanks
Mike

 

[Little Bill]

It is allowed as far as I know, under a tap conductor. It has to meet those rules, but that's not very hard.
Thanks
Mike

Maybe in Chicago, but not here. Switch leg conductors have to match the circuit supplying them.
It used to be allowed (by inspectors) but not now.

 

[kwired]

But it most often installed that way.
Thanks
Mike

I see it run as an individual outlet a lot, but it is always a 15 amp duplex receptacle at the washer location and not a single receptacle.

It is allowed as far as I know, under a tap conductor. It has to meet those rules, but that's not very hard.
Thanks
Mike

If it is a feeder tap, it must end in an overcurrent device. If it is a tap to a luminaire, that permitted tap doesn't include the switch loop, it would just be a reduced size conductor from a junction point through a relatively short cable, cord, raceway to the luminaire.

 

[jap]

It is allowed as far as I know, under a tap conductor. It has to meet those rules, but that's not very hard.
Thanks
Mike

What tap rule allows you to put 14ga wire on a 20a Circuit?

 

[jap]

The NEC is designed to prevent fires, not make sense.

I'd have to disagree with this.

Although there are a few things in it that dont make sense, the majority of it makes perfect sense.

 

[mike1061]

What tap rule allows you to put 14ga wire on a 20a Circuit?

Well, I just spent 15 minutes looking and can't find it. There used to be a paragraph that siad something like Tap conductors. Taps conductors are permited if the following are meat. It was in a list form. Something like this 1, 25 feet or less. 2. Must be continuis. 3. Must be sized for the load. and maybe something else. I'll try to find it.
Thanks
Mike

 

[mike1061]

I see it run as an individual outlet a lot, but it is always a 15 amp duplex receptacle at the washer location and not a single receptacle.

That's what I'm saying. I always thought it should have been a 20 amp recpt though.

If it is a feeder tap, it must end in an overcurrent device. If it is a tap to a luminaire, that permitted tap doesn't include the switch loop, it would just be a reduced size conductor from a junction point through a relatively short cable, cord, raceway to the luminaire.

I didn't mean a feeder, I'm looking for the article. I'll post if I can find it.
Thanks
Mike

 

[mike1061]

I can't find it. I'm really sorry.
I don't have an explamation. I remember it clearly. I can even picture it, on the lower corner of the left page. But then again, I'm begining to feel like I'm way of base here.
I can remember one instructor I had talking about it, me not understanding what he meant, asking if he was refering to a splice (adding an extension to a circuit with the same size conductors), and him saying "that wouldn't be a splice". That was the moment when I figured out the difference.
Thanks
Mike