USB Receptacle
- Thread starter Dennis Alwon
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K8MHZ
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- Electrician
A picture is worth 1000 words
K8MHZ
Senior Member
- Occupation
- Electrician
K8MHZ
Senior Member
- Occupation
- Electrician
[h=1]USB Type A Receptacle, PCB Mount (Right-Angle SMD)[/h]
http://www.electrontubestore.com/index.php?main_page=product_info&cPath=37_82&products_id=259
http://www.electrontubestore.com/index.php?main_page=product_info&cPath=37_82&products_id=259
K8MHZ
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- Electrician
What has the 'AC feed's point of view' got to do with anything?
The NEC does not specify if AC or DC is used. Read the NEC definition of 'receptacle'. Also, as I have illustrated with pictures from the 'net, it is the industry standard to call them receptacles.
The UL defines 'receptacle' as 'A female contact device intended to be installed on a wiring system to supply current to utilization equipment'. In the case of the OT, the current is 2.1 amps. The utilization equipment would be cell phones or iPads, etc. And, like the NEC, does not specify AC or DC or voltage.
So, until some changes are made by the NFPA, the UL and industry at large,USB contact devices that allow a plug to make a connection to a cable are receptacles.
K8MHZ
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Since the NEC does'nt define outlet in terms of voltage or current, should I consider the water dispenser on my refrigerator an additional oultet since the refrigerator is plugged into an electrical outlet?
Did you read the NEC's definitions of outlets and receptacles? The above indicates you may have not.
To me its not about the wording of the definiton.
Sometimes I think too much emphasis is put into the "Wording" of things.
I just think there should be a better dividing line between Line Voltage outlets and Low Voltage outlets.
To me, putting the USB Outlets and 120v Receptacle outlets in the same category doesnt seem right just because of the wording but that's JMHO.
JAP>
Sometimes I think too much emphasis is put into the "Wording" of things.
I just think there should be a better dividing line between Line Voltage outlets and Low Voltage outlets.
To me, putting the USB Outlets and 120v Receptacle outlets in the same category doesnt seem right just because of the wording but that's JMHO.
JAP>
Your right, The USB Contact is in fact a "Receptacle".
But does it not make a difference that the charging circuitry ahead of this receptacle is Hard wired to the branch circuit?
The Hard Wired Charging Circuitry ahead of the USB Receptacles is the grey area for me.
JAP>
If an external USB charger is plugged into a 120v receptacle to charge a phone, then I would consider the charger Utilization Equipment not another outlet.
Does this change simply because the charger in the Combo Receptacle/USB device we are talking about is hardwired to the branch circuit instead of being plugged in?
Does this change simply because the charger in the Combo Receptacle/USB device we are talking about is hardwired to the branch circuit instead of being plugged in?
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What JAP said!
Is a device which contains a 120 volt receptacle and Type F coax cable jack a duplex receptacle? There there is no active device associated with the cable jack but there is a communications wiring system behind it.
I would call this "complicated" and a combination of features and equipment which was not contemplated at the time the definition was written. Therefore the definition does not apply well.
1. If this were a wall wart to serve the same purpose, it would, I think, be agreed that the wall wart is utilization equipment whose purpose is to supply power to other utilization equipment and that output power is not carried through a wiring system, or at least not one which is part of the building. In the case of a power brick, the separation is even clearer. The wiring from the brick to the computer, etc. is covered by UL, but is not directly addressed by the NEC.
2. In this case, we have moved the wall wart into the device itself and contained it entirely within the wall box. That blurs the distinction between utilization equipment and the associated receptacles/outlets.
3. The "USB ports" in this device are not actually USB ports in that there is no data interconnection to other devices, indeed no data wire connections at all. This is simply a power supply which uses the power provisions of the USB specification to deliver its output. There should be an official designation for a power-only USB receptacle.
4. The original convention for use of USB connector Series A and B was that a Series A connector was used on a USB master port, such as a computer, and the Series B connector was used on a peripheral device to be attached via USB to that computer. Now we have, in addition to using Series A at both ends, mini-USB (trapezoid) and micro-USB (oval) connectors as well as the mechanically incompatible USB 3.0 connector for high speed wiring, which still supports USB 1 and 2 communications as well!
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To me an Outlet is just that, a place where you connect a "Load" not a "Load" in itself.
Utilization equipment is a Load.
To me the built in charger in the Combo Receptacle/USB Charger device is a Load that has Outlets on its Secondary.
Although all are "Outlets" on the strap, the load between the branch circiut and the USB Receptacle Outlets (Load being the Charger) makes me feel like the 120v receptacle should be the only thing counted as an outlet.
To me this is (1) 120v receptacle outlet and (1) piece of Utilization equipment tied to the line side of it.
Utilization equipment is a Load.
To me the built in charger in the Combo Receptacle/USB Charger device is a Load that has Outlets on its Secondary.
Although all are "Outlets" on the strap, the load between the branch circiut and the USB Receptacle Outlets (Load being the Charger) makes me feel like the 120v receptacle should be the only thing counted as an outlet.
To me this is (1) 120v receptacle outlet and (1) piece of Utilization equipment tied to the line side of it.
Wow, man that was well put,,,,, I wish I could explain myself as good as you guys.
I need to quit trying to explain my point in typing it just gets me deeper into trouble.
I wish we could all get on a conference call sometimes, I bet we could hash things out pretty quickly.
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- Retired PV System Designer
K8MHZ
Senior Member
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- Electrician
That is a good question, but a coax connector is not a receptacle as per NEC definition, because it is not connected the the NEC's definition of an outlet, which defined as a point in which current is taken to supply utilization equipment.
We can use the following 'litmus test' based upon the NEC's definitions.
If the answers to all the following are 'yes', then the device is a receptacle. (per the NEC and UL)
1) Is the device a contact device?
2) Is the device installed at a point on the wiring system where current is taken to supply utilization equipment?
3) Is the device for the connection of an attachment plug that establishes a connection between the conductors of the flexible cord attached to the plug and the conductors permanently connected to the device?
K8MHZ
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- Electrician
Too bad we can't get the NFPA's or UL's answer in writing. Besides that which is already written, I mean.
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- Placerville, CA, USA
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FWIW, in many Satellite and preamp-using OverThe Air OTA) TV coax connections, the coax is in fact carrying DC to load equipment, and that DC may be injected at any point along the cable, including on the room side of coax jacks (an inlet?), with the utilization equipment cable being connected to another coax jack. Picky, but codes roll that way sometimes.
Similarly a CAT5 connector may be carrying just data or may also be carrying power to remote utilization equipment. The connector does not know the difference.
Thanks for calling attention to this part of the test. In the case in point, it does not establish a connection between conductors of the plug and conductors permanently connected to the device, since the low voltage wires are not connected to the AC wires and do not leave the device anywhere except on the faceplate temporary connectors.
By that same token, you could argue that a pair of screw terminals from the secondary side of a doorbell transformer contained within an outlet box do not constitute an outlet both because of the lack of an attachment plug and flexible cord and because there is no connection of those wires to conductors permanently connected to the device. There is certainly power transfer, but no *connection*.
K8MHZ
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- Electrician
FWIW, in many Satellite and preamp-using OverThe Air OTA) TV coax connections, the coax is in fact carrying DC to load equipment, and that DC may be injected at any point along the cable, including on the room side of coax jacks (an inlet?), with the utilization equipment cable being connected to another coax jack. Picky, but codes roll that way sometimes.
Similarly a CAT5 connector may be carrying just data or may also be carrying power to remote utilization equipment. The connector does not know the difference.
I thought about that. Because I have a pre-amp and OTA. In order to be a receptacle, the device must supply current, not use it.
How are the low voltage wires not permanently connected to the device in question? No one ever said the USB devices were AC receptacles. They are not, but they still qualify as receptacles.
By that same token, you could argue that a pair of screw terminals from the secondary side of a doorbell transformer contained within an outlet box do not constitute an outlet both because of the lack of an attachment plug and flexible cord and because there is no connection of those wires to conductors permanently connected to the device. There is certainly power transfer, but no *connection*.
No, the definition of an outlet does not require connection to a plug and a cord. That is part of the definition of a receptacle. They are two different things. The terms are not interchangeable.
Sierrasparky
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Other than a retrofit. Why would you want to put a single one on a 20 amp circuit? What is the point. It is a waste of wire.
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