Large Receptacle load calculations

[tvgaconsultants]

I have a 200 amp receptacle and a 60 amp (208 volt 3 phase) receptacle to be placed in long runs. What should I do to get the load current to determine wire sizing and circuit protection? I do not know what size loading the enduser will place on these circuits.

[ June 04, 2003, 04:43 PM: Message edited by: tvgaconsultants ]

 

[jtb]

Re: Large Receptacle load calculations

I think you need to contact the end user for info.
Do you know what type of equipment these receptacles are for? If so, you could contact vendors for rough info. Sizing of OL will depend on motor nameplate, so you can't spec until unit is selected.

 

[tvgaconsultants]

Re: Large Receptacle load calculations

The system is for wetaring bragdes. Mainly pumps and the like. Is there some derating available or should i use the receptacle rating.

 

[jtb]

Re: Large Receptacle load calculations

wetaring bragdes ???

You lost me.

How did you size the receptacles??

[ June 04, 2003, 07:29 PM: Message edited by: jtb ]

 

[frenchelectrican]

Re: Large Receptacle load calculations

200 amp repectaile ???? are you talking about pin and sleeve devices ?? i have listing for 63 and 100 amp devices but i cant find the 200 amp at all i belive it is crose hinde compaine do make that large i am not sure .. but for that super size better get somekind of interlocking switch on it to prevent power turn on if not plug in fully or vise version i will try to dig up info if i can find it


merci marc

 

[tvgaconsultants]

Re: Large Receptacle load calculations

jtb,
proof reading is not my speciality. DEWATERING BARGES. YOU KNOW LARGE PUMPING STATION LOCATED ON A BOAT. SORRY, THE SIZE WAS CLIENT DRIVEN.

 

[tvgaconsultants]

Re: Large Receptacle load calculations

FRENCH ELECTRICIAN,
Both Appleton and Crouse-Hinds manufacture a 200A pin and sleeve receptacle. My question was not with acquisition of the product but the system t feed. Can I reduce the receptacle rating via NEC for purposes of wire sizing? Currently I am not reducing at all due to not knowing the load quanity the cleint will place on this circuit.

 

[iwire]

Re: Large Receptacle load calculations

Code wise you could feed it with 12 AWG with 20 amp overcurrent protection.

210.21(B) Receptacles.
(1) Single Receptacle on an Individual Branch Circuit. A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.

But if I was the client that asked and paid for a 200 amp outlet I would expect it to be fed with 200 amp wire and overcurrent protection.

by tvgaconsultants

Can I reduce the receptacle rating via NEC for purposes of wire sizing?

The NEC would allow you to reduce the size of the feed but how can you if you do not know the load to be connected?

by frenchelectrican

but for that super size better get somekind of interlocking switch on it to prevent power turn on if not plug in fully or vise version

Marc I know Meltric corp. makes an outlet rated at 200 amp 480 volt and rated as a disconnect switch. You can make and break under load.

Meltric Corp.
Bob

[ June 09, 2003, 07:53 PM: Message edited by: iwire ]

 

[frenchelectrican]

Re: Large Receptacle load calculations

ahh merci (thanks) bob for finding it and i am suprised that the company make that plug attchement is not far from my home and i will swing by them some day when i get time to look more closer with it and yeah i know you say it rated for make and break under load and i know few devices are NOT for make and break underload it will show on the listing ..


tvconsultans:if i was in your feet if i do not know what type of load they will conneted i will stay with max. wire sized load at conutunis rating. remeber that dewater pump do intend to be running more like contunius load (more than 3 hours running time ) but if that pin and sleeve attachment is rated for full load you can run up to the 200 amp other wise back off to 160 amp load to prevent getting warm with pin and sleeve devices i know cam lock device can take full load easy with out side effects so therefore my opion and bob's we will say better set up for full 200 amps overcurrent devices and i am sure appleton and crose-hind companies do have 200 amp pin and sleeve rating for full load but best thing to is check the spec to make sure it is ok for it

merci marc

 

[tvgaconsultants]

Re: Large Receptacle load calculations

Bob,
I know all about MELTRIC components, but that would require different plug and receptacle ends for my client (not very desirable). I do appreciate the information about reducing, I was just checking to see if I could save them some money and have a by the code design. I will stick with my pervious design for full load rating.

Marc,
I agree with your concept that a disconnecting device be placed at, in or on the receptacle. My client has established procedures for operation of this type equipment. This is why I have not designed the safety device into the system at, in or on the receptacle. The other is that my client says that the barges CAN use above 150 Amp.(Their not sure of the total load on the system) That is why they requested a 200 A receptacle. Thanks for the information. It is great to be able to bounce ideas and get some feedback. I really appreciate the courteously.