30 amp outlets on 20 amp circuits.

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stew

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federal way,washington
Is there any code reference that wont allow a receptacle larger than the ampacity of the circuit? Specifically using a 20 amp circiut and installing a 30 for convenience.
 
For a branch circuit serving only one receptacle, it is allowed. 210.20(B)(1) For multiple receptacles on a branch circuit, it is generally not allowed. 210.20(B)(3).

Cheers, Wayne
 
I agree with Wayne but I'm curious as to why you would put a 30 amp receptacles on a 20 amp circuit.
 
In a dry storage boatyard
In order to deter folks from using too much power they are on a 20 amp cirvuit to.limit the use. However the normal shore power cord you would use for pier shore power normally are 30 amp.twist lock. So its a. twofold reason..limitation and convenience. This is in a dry storage lot. 2 things actually come into play the requirement in 55a
 
stew said:
In a dry storage boatyard
In order to deter folks from using too much power they are on a 20 amp cirvuit to.limit the use. However the normal shore power cord you would use for pier shore power normally are 30 amp.twist lock. So its a. twofold reason..limitation and convenience. This is in a dry storage lot. 2 things actually come into play the requirement in 555 a4 that the receptacle be 30amp or more and the statement in
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555.33 Receptacles.
Receptacles shall be mounted not less than 305 mm (12 in.) above the deck surface of the pier and not below the electrical datum plane on a fixed pier.
555.33(A) Shore Power Receptacles.
555.33(A)(1) Enclosures.
Receptacles intended to supply shore power to boats shall be enclosed in listed marina power outlets, enclosures listed for wet locations, or shall be installed in listed enclosures protected from the weather. The integrity of the assembly shall not be affected when the receptacles are in use with any type of booted or nonbooted attachment plug/cap inserted. 555.33(A)(2) Strain Relief. Means shall be provided where necessary to reduce the strain on the plug and receptacle caused by the weight and catenary angle of the shore power cord. 555.33(A)(3) Branch Circuits. Each single receptacle that supplies shore power to boats shall be supplied from a marina power outlet or panelboard by an individual branch circuit of the voltage class and rating corresponding to the rating of the receptacle.
Informational Note: Supplying receptacles at voltages other than the voltages marked on the receptacle may cause overheating or malfunctioning of connected equipment, for example, supplying single-phase,
120/240-volt, 3-wire loads from a 208Y/120-volt, 3-wire source.
555.33(A)(4) Ratings.
Shore power for boats shall be provided by single receptacles rated not less than 30 amperes.
Informational Note: For locking- and grounding-type receptacles for auxiliary power to boats, see NFPA 303-2016, Fire Protection Standard for Marinas and Boatyards.
(a)Receptacles rated 30 amperes and 50 amperes shall be of the locking and grounding type.
Informational Note: For various configurations and ratings of locking- and grounding-type receptacles and caps, see ANSI/NEMA WD 6-2016, Wiring Devices — Dimensional Specifications.
(b)Receptacles rated 60 amperes or higher shall be of the pin and sleeve type.
Informational Note: For various configurations and ratings of pin and sleeve receptacles, see ANSI/UL 1686, UL Standard for Safety Pin and Sleeve Configurations.
555.33(B) Other Than Shore Power.
555.33(B)(1) Ground-Fault Circuit-Interrupter (GFCI) Protection for Personnel.
Receptacles in other locations shall be protected in accordance with 210.8.
555.33(B)(2) Marking.
Receptacles other than those supplying shore power to boats shall be permitted to be enclosed in marina power outlets with the receptacles that provide shore power to boats, provided the receptacles are marked to clearly indicate that the receptacles are not to be used to supply power to boats.
555.33(C) Replacement Receptacles.
The requirements in 555.33 shall apply to the replacement of marina receptacles.
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2020 NEC.
 
Use a 20 amp receptacle, RV owners can use a 30 to 20 adapter, if the CB trips its their issue. Post sign saying limited to 20 amps or 2400 watts.
 
SSDriver said:
Annother senario;

My welder has a 50amp range plug on it but says to use a maximum 20amp breaker.
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A range plug was never permitted for welders, they are dual voltage non grounding 125/250V rated, although were common, but were cheaper then a 50A 250V product, when it was still the standard for ranges.

One solution for the OP is to meter the outlets, having to pay for something teaches conservation.
 
stew said:
Statement in 220b1 that allows it. Not sure if 555.33a3 rules ir out tho
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You have to comply with both. Here, 555.33a3 is more restrictive, and more specific.

Each single receptacle that supplies shore power to boats shall be supplied from a marina power outlet or panelboard by an individual branch circuit of the voltage class and rating corresponding to the rating of the receptacle.
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To me that clearly rules out putting 30A receptacles on a 20A circuit. The way I read it, every receptacle for shore power must be a 30A receptacle, and every one must be supplied by an individual 30A circuit.
 
norcal said:
A range plug was never permitted for welders, they are dual voltage non grounding 125/250V rated, although were common, but were cheaper then a 50A 250V product, when it was still the standard for ranges.

One solution for the OP is to meter the outlets, having to pay for something teaches conservation.
Click to expand...
Sorry I just meant a 50 amp (6-50) plug. And the welder says to protect with a 20 amp breaker. A lot of newer welders still use that plug but have internal fuses. A lot of the older welders don't have internal fuses and require the installer to provide the OCPD that is less than 50 amps using that style plug.
 
SSDriver said:
Sorry I just meant a 50 amp (6-50) plug. And the welder says to protect with a 20 amp breaker. A lot of newer welders still use that plug but have internal fuses. A lot of the older welders don't have internal fuses and require the installer to provide the OCPD that is less than 50 amps using that style plug.
Click to expand...
There are some different rules for welders based on the duty cycle.
 
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