Receptacle Configuration

[Machiavelli999]

I have got a piece of equipment that came out with a L23-30P plug. That is a 600V rated, 3PH, 5 wire (3H, N, G) plug.

However, the equipment actually requires a 208/120V, 1PH, 4 wire (2H, N, G) connection. The equipment vendor claims that they have always done it this way and that they "just leave one phase connection empty". Is that acceptable per NEC code?

I was going to simply provide a L23-30R receptacle but wire it up for only 208V/120V, 1PH connection. Then maybe provide a label indicating that this outlet is only for this equipment and that one of the phases is disconnected.

It's sloppy, but I am afraid that simply taking the plug off and changing it would nullify the UL listing on the equipment.

 

[iwire]

I think this

406.3 Receptacle Rating and Type.
(A) Receptacles. Receptacles shall be listed and marked
with the manufacturer?s name or identification and voltage
and ampere ratings.

results in a violation of

110.3 Examination, Identification, Installation, and Use
of Equipment.
(B) Installation and Use. Listed or labeled equipment
shall be installed and used in accordance with any instructions
included in the listing or labeling.

if you install a L23-30R on a 208 volt system.

 

[Machiavelli999]

Hmm...but does a L23-30R receptacle come with specific instructions that say you must hook up 600V, 3 phase on it? Isn't that just the rating of the receptacle. And since my 208V circuit does not exceed the rating of the receptacle, shouldn't it be OK?

 

[iwire]

Hmm...but does a L23-30R receptacle come with specific instructions that say you must hook up 600V, 3 phase on it? Isn't that just the rating of the receptacle. And since my 208V circuit does not exceed the rating of the receptacle, shouldn't it be OK?

My opinion is that the receptacle is listed, it is labeled with a specific value and 110.3(B) requires us to follow the labeling.



But I am not the AHJ and it could be interpreted in many ways.

 

[maghazadeh]

I have got a piece of equipment that came out with a L23-30P plug. That is a 600V rated, 3PH, 5 wire (3H, N, G) plug.

However, the equipment actually requires a 208/120V, 1PH, 4 wire (2H, N, G) connection. The equipment vendor claims that they have always done it this way and that they "just leave one phase connection empty". Is that acceptable per NEC code?

I was going to simply provide a L23-30R receptacle but wire it up for only 208V/120V, 1PH connection. Then maybe provide a label indicating that this outlet is only for this equipment and that one of the phases is disconnected.

It's sloppy, but I am afraid that simply taking the plug off and changing it would nullify the UL listing on the equipment.

I think your way is okey for following reasons;
1) NEC allows to have a 480, 600 V cb or disconnect switch to be installed on a 208 0r
240V system.
2) NEC allaws to use 1 or 2 pole of a 3ploe CB or disconnect switch.
3) Based on your equipment vendor, manufacturer send this eqmt. with the L23-30p,
so if your client needs equipment replacement your receptacle will match the new
unit's plug.

The only foreseen problem would be future electrician's confusion which if you label it will avoid that too.

 

[Volta]

My opinion is that the receptacle is listed, it is labeled with a specific value and 110.3(B) requires us to follow the labeling.



But I am not the AHJ and it could be interpreted in many ways.

But I assume you would feel ok installing a 250 volt receptacle on a 208 volt circuit.

I think it is compliant, unless as Iwire implied instructions were included in the listing for that device that limit the lower system voltage range.