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The national electrical code is a publication thet governs commercial, residential and industrial electrical installations. Article 250 is the section governing grounding and bonding installations.
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What is color code of 250 ohm resistor?
Green Red Brown
How do you determine the ground wire size for a single phase 400 amp service?
I assume we are talking about 120/240V service somewhere in the US, and that you are using copper wire! You must consult the NEC (National Electric Code) or other code your municipality uses. It must be the year of issue that your municipality has adopted AS AMMENDED by that municipality. Many cities do not adopt the codes as-is, they change things here and there. Get a copy, or hire someone who knows this stuff. Using the plain 2005 NEC, I would go to article 230 - Services. It tells me the size of the grounded conductor depends on the size of the ungrounded service entrance conductors, so I have to know that first. 230.42A tells me the ungrounded conductors are sized according to 310.15, so I go to article 310, Conductors and look at table 310.15(B)(C). It says your 400 Amp service will use 400 kcmil wire for the ungrounded conductors. Back to article 230. Paragraph 230.42C says to size the grounded conductor according to 250.24C, so I turn over to article 250, Grounding. 250.24C sends me to table 250.66. Table 250.66 says that for service entrance conductors over 350 kcmil and less than 600 kcmil, the grounded conductor would be 1/0. There are a few exceptions and circumstances that could change the answer, but you get the idea. As you can see, this is not trivial, and mistakes will be costly. Hire a pro to do the calcs for you. Unless this is a homework or test question. In that case, you're welcome... If you're asking this question you shouldn't be installing an electrical service. Asking this type of question usually means you aren't ready to do this yourself. Study some electrical material and the National Electrical Code, or call a professional electrician. If someone were to give you an answer here, you might attempt to do something you shouldn't be doing, and that may cost someone a shock, a home fire, or their life. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS. If you do this work yourself, always turn off the powerat the breaker box/fuse panel BEFORE you attempt to do any workANDalways use an electricians test meter having metal-tipped probes(not a simple proximity voltage indicator)to insure the circuit is, in fact, de-energized.
Why you use 250 Ohm resistor in series with HART protocol communication?
You need to use the 250 Ohm resistor in series with HART protocol communication because it acts as a shunt resistor.
How many amps can a 250 va transformer carry?
A transformer is a power source. It will provide voltage to a device. Find the voltage rating on the device, say 24V. 250/24 = ~10A.
How many 250 kcmil cable in 5 inch conduit?
ONE
What section of the nec covers grounding?
Article 250 of the National Electrical Code covers grounding.
Which fnb branch has branch code 250409?
The branch code 250-409 is assigned to First National Bank (South Africa), Roodeport Branch, Johannesburg.
NEC Article 250 covers what?
Grounding
How do you start a Yamaha ttr 230 and 250?
electric start on the 230 i believe theres both electric and kick start on the 250 not sure though.
What country has country code number plus 250?
Telephone country code +250 is Rwanda, in Africa.
Is the 2014 Lexus IS-250 electric or gas?
The 2014 Lexus IS-250 is a gas-powered vehicle.
Is the 2009 Lexus IS-250 electric or gas?
The 2009 Lexus IS-250 is a gas-powered vehicle.
Is the 2010 Lexus IS-250 electric or gas?
The 2010 Lexus IS-250 is a gas-powered vehicle.
Is the 2006 Lexus IS-250 electric or gas?
The 2006 Lexus IS-250 is a gas-powered vehicle.
Is the 2013 Lexus IS-250 electric or gas?
The 2013 Lexus IS-250 is a gas-powered vehicle.
Is the 2011 Lexus IS-250 electric or gas?
The 2011 Lexus IS-250 is a gas-powered vehicle.
Is the 2008 Lexus IS-250 electric or gas?
The 2008 Lexus IS-250 is a gas-powered vehicle.
