Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations SSS148 on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Receptacles in Industrial Facility

Status
Not open for further replies.

Timm1

Electrical
Apr 13, 2009
12
What kind of receptacles should be used in an industrial facility (single or duplex)? The NEC code does not say anything about it.
 
Replies continue below

Recommended for you

Don't think it matters.
We have both single (typically for 208V/220V or 20A rated 120V circuits) and regular 15A rated duplex at my facility.
 
Right. You can use either on a multioutlet branch circuit. A single receptacle would be required on a branch circuit intended to supply only a single load.
 
We nearly always use duplex, heavy-duty type or hard-use type.

Alan
----
"It’s always fun to do the impossible." - Walt Disney
 
I see on the web that a heavy duty duplex receptacle is 1800 X 2 =3600 Watts total. The normal duplex receptacle is also 1800 X 2 =3600 Watts. How is heavy duty receptacle different than the normal receptacle?
 
"Typically" heavy duty (from a reputable manufacturer) carries a 20A rating where standard is 15A rating...
But I have seen "heavy duty" being added to the description of standard 15A rated outlets also...
 
the heavy duty is related more to how robust the device is, rather than the current rating. things like retention will be stronger, can be subject to more abuse etc.
 
How many duplex receptacles can be placed on 15A 120V circuit? The code does not say anything about this.

If we allow 180 kVA for one receptacle (360 kVA for duplex), then it looks that I can put a maximum of four duplex receptacles on a 15 A circuit.
 
There is no limit to the number of outlets.. The fuse/breaker protecting that whole circuit takes care to ensure that the current is not exceeded.
 
Only in residential units foe general iighting is the number of receptacles un limited per circuit.
All others establishments is 180 VA per receptacle
That is 8 per 15 amp circuit.
 
Timm1,
We usually try not to exceed 6 duplex recap. per 120V circuit in case of possible future additions. Note that this only applies to general purpose receptacles where you assume 180VA per duplex recap. In other cases, the client , most of the time” could tell you what could possibly be plugged into those receptacles with more precise load information. Examples include kitchen and break rooms where they might need dedicated circuits for microwaves and such equipment where you cannot assume 180VA per receptacle. Try to find out possible loads that might be connected to those receptacles, otherwise use 180VA per duplex receptacle if they are for general purpose.

Please note that a typical duplex receptacle which I think you refer to as “one receptacle” contains two(2) NEMA 5-15R receptacles in assembly for which you should assume the 180VA, and a double duplex receptacle would be what I think you refer to as a duplex which would be 360VA/assembly.
Duplex = 180VA
Double Duplex = 2*180VA


"Throughout space there is energy. Is this energy static or kinetic! If static our hopes are in vain; if kinetic — and this we know it is, for certain — then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature". – Nikola Tesla
 
I understand that when you say 180 VA per receptacle, it is for single receptacle. For duplex, it will be 360 VA per receptacle, which means a total of 4 receptacles per 15 A breaker. Am I right?
 
Never mind, I think I have clear understanding now. A single receptacle is 90VA, duplex is 180VA, and double duplex is 360VA.
 
this is an industrial building, if they are just housekeeping receptacles, treat them accordingly. In a typical industrial setting, you need to find out about what is happening and this will drive the design!
 
Go to your local Lowe's or Home Depot and pick the most expensive and cheapest receptacles off the shelf and check the difference. The expensive ones are typically heavier in weight and in visible construction. Well worth it in applications where they will be plugged into a lot.

 
OT a little, but the only other receptacles I’ve come across with any regularity in industrials are Appleton { } or Crouse-Hinds pin-and-sleeve, 60-ampere, 3ø 480-volt devices, interlocked with XOP disconnect switches for maintenance welders.
 
Heavy duty receptacles are those that can withstand repeated use over a long period of time without degrading the contact wipe pressure, terminal screw torgue, ground prong withdraw pressure, etc.... They have heave weight, single piece ground straps, tough phenolic or nylon faces,and the ground prong entry port will not snap off after a few operations. They are available in all voltage, amperage and NEMA, (in us) configurations. It depends on what loads you need to serve.

The loading is 180VA, (not kVA), per general use device. Whether it is a single or duplex device, (a double duplex device is counted as two). It can be straight blade, locking type, special blade, pin and sleeve, whatever the load calls for. You can put 10 devices on a 20A, 120V, circuit, (10 x 180VA= 1800VA) < ( 20A x 120V x 80% = 1960VA). And similarly 8 devices on a 15 A circuit.

Back to the original question, I would definiately recommend a heavy duty, nylon faced, 20A receptacle for an industrial application. We expect heavy use, difficult environment and long service expectations. I would definitely recommend, by far Hubbell-Kellums wiring devices. Look at
You can't go wrong with these. I've specified these devices, (and their predecessors), for almost thirty years. Dependable, quality devices.

Just MHO,
EEJaime
 
EEjamie: Have you used their "SNAPConnect" line?

Alan
----
"It’s always fun to do the impossible." - Walt Disney
 
From the '08 NEC:
"220-14-I: Receptacle Outlets. Except as covered in 220.14(J) and (K), receptacle outlets shall be calculated at not less than 180 volt-amperes for each single or for each multiple receptacle on one yoke. A single piece of equipment consisting of a multiple receptacle comprised of four or more receptacles shall be calculated at not less than 90 volt-amperes per receptacle."

Either a single or duplex (two outlets on one yoke) unit shall be calculated at 180VA. Four or more receptacles in one 'piece of equipment' may use the 90VA figure. So using a single or a duplex unit per location makes no difference.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor