m sleem

Please confirm:

Breaker size of motor is equal to 2.5*rating current...(assume 100A)

Feeder size should carry out 100A or less ?

disconnect switch will be sized to 100A OR more ?

wildleg

what version of the NEC are you on ?

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m sleem

2011....

wildleg

that's odd, because I can't find any indication that Egypt is using the NEC

read article 430

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As President Roosevelt said: "We have nothing to fear but fear itself. And Chuck Norris. And 滿口胡言. And Grabthar's hammer. And Gort. and 江南 Style. and rotting in the street and Zombies . . . and Wayne Griffen "

m sleem

i'm egyptian but i'm working in saudi arabia. regardless my nationality shall we discuss seriously.

mbednarik

you need to ref the tables in 430 part XIV to find the FLA for a given motor. Use the amperage given in the tables, not the nameplate to figure conductor sizing and the ground fault and short circuit protection. The overload protection should be sized by the nameplate on the motor. Example you have a 10 horsepower single phase 230 volt motor to be used continuously. Table 430.248 says 50 amps. 50 X 1.25 = 62.5. The disconnect has to be rated for 115% of the table FLA. The GF/SC device will be sized with table 430.52. The inverse time breaker for a 10 HP motor could be 150 amp. The overload protection device should be sized at 130% unless it has a service factor of 1.15 or greater or a makred temp rise of 40 deg C or less. Then the overload device can be set at 140% FLA or nameplate. So if your motor had a nameplate of 45 amp your overload device should trip at 58.5. Be careful with the overloads, some have the 130% built in so you set the overload at your nameplate FLA.

wildleg

first of all, a serious discussion of the above would mean that you would have at least attempted to read the appropriate article of the NEC. article 430 has very specific instructions for your question.

secondly, this has nothing to do with your nationality. "Location" assumes location.

thirdly, I tried to find the electric code for saudi, but can't find what is common. Does the Saudi National Building Code specify an electrical code or are you working on base ?

lastly, I was going to make a funny comment, so I looked up Bedouin nomads for pics. I found the following pic from National Geographic, and was suprised at two things: 1) they have what appear to be line voltage lighting in their tent, and 2) the gentleman sitting opposite at the bottom appears to be eating with both hands

__________________
As President Roosevelt said: "We have nothing to fear but fear itself. And Chuck Norris. And 滿口胡言. And Grabthar's hammer. And Gort. and 江南 Style. and rotting in the street and Zombies . . . and Wayne Griffen "

wildleg

I looked around, and apparently the code which currently applies to Saudi Arabia is the Saudi Building Code 2007 ? Section 401 details electrical applications. I haven't had time to read it. here is a link:

http://www.alriyadh.gov.sa/ar/subsit...9%8A%D8%A9.pdf

unless you are on a base that is a territory of another country, I believe the above code applies, not the NEC.

__________________
As President Roosevelt said: "We have nothing to fear but fear itself. And Chuck Norris. And 滿口胡言. And Grabthar's hammer. And Gort. and 江南 Style. and rotting in the street and Zombies . . . and Wayne Griffen "

m sleem

not very helpful .........leave it

wildleg

ok, I confirmed that the NEC does not apply, so all the other replies to your motor feeder thread simply do not apply, unless you are not in a Saudi Arabian territory. This is from article 401 of the Saudi Building Code (Electrical)

12-3

Selection of electrical equipment

12-3.1

General

Every item of electrical equipment used in electrical installations shall
comply with the relevant Saudi standards as are appropriate. In the absence
of Saudi standards, the equipment shall comply with the appropriate
international standards (IEC, ISO, or ITU). Where there are no applicable
standards the item of equipment concerned shall be selected by special

agreement

__________________
As President Roosevelt said: "We have nothing to fear but fear itself. And Chuck Norris. And 滿口胡言. And Grabthar's hammer. And Gort. and 江南 Style. and rotting in the street and Zombies . . . and Wayne Griffen "

m sleem

erics37

To the OP, read the post by mbednarik.

Short circuit and ground fault protective devices are sized in the NEC based on the full load current from Table 430.248 and 430.250 (for single phase and 3 phase, respectively). It also depends on what type of overcurrent device you are using. Fuses are sized differently than circuit breakers, for instance.

Step 1: Determine the motor you are using, and look up the appropriate full load current value in the Tables I mentioned above.
Step 2: Size overload protection from 430.32
Step 3: Branch circuit wire size from 430.22
Step 4: Branch circuit overcurrent device, Table 430.52
Step 5: Feeder wire size, 430.24
Step 6: Feeder overcurrent device, 430.62

Wow dude, you're being a real d!ck in this thread.

wildleg

AFAIK, not adhering to the express wishes of HRH and/or the crown prince are stoning offenses (?)

the OP says he is in Saudi, and want NEC code references ? If you were in Canada would you use the electrical code from, say, Germany ?

__________________
As President Roosevelt said: "We have nothing to fear but fear itself. And Chuck Norris. And 滿口胡言. And Grabthar's hammer. And Gort. and 江南 Style. and rotting in the street and Zombies . . . and Wayne Griffen "

frenchelectrican

Wildleg .,

Belive or not most other area can use the NEC or IEC depending on what they agree with it and I know alot of equiment they used in Saudi Arabia can use either way ( both NEC or IEC ) so they can follow either regulations.

m sleem.,

Did you read mbednarik's comment on the posting here ? if so this is a proper way to do it.

Merci,
Marc

__________________
Bleu est beau.

wildleg

Marc,

I realize that's the way it used to be, but their current code which it appears they implemented in 2007 only references the IEC and those other codes, so wouldn't it make sense to use those codes, rather than the NEC, which they don't reference at all (as far as I can tell) ? I have never opened the IEC, does it reference the NEC ? what am I missing ?

__________________
As President Roosevelt said: "We have nothing to fear but fear itself. And Chuck Norris. And 滿口胡言. And Grabthar's hammer. And Gort. and 江南 Style. and rotting in the street and Zombies . . . and Wayne Griffen "

nolabama

What is the nameplate rating in current of the motor your sizing. Horsepower and voltage would also be helpful.

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frenchelectrican

Wildleg.,

I know it kinda give ya a little suprised however I know they did use the IEC codes but they did allow expandation with NEC code so they use either one depending on inspector in that area rather to use.

There are few part in IEC code is stricter than NEC and some are the other way around so it kinda like catch 22.

I will check into little more deeper for other areas due I am well verised with either NEC or ENF or ECF ( Electrquie Nomes De France or Electrical code of France ) so give me a little time to check out on that part.

But I belive that the local goverment may have the final call on which code edition they can use and some case they can use both.

Merci,
Marc

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Bleu est beau.