My post started with "To clarify, there are limits on the panel and the service". This is in response to you saying "No where in the electrical code will you see a limit on how much you can run your main panel". Your post said there are no limits, I just wanted to clarify that for people as there are limits to how much you can run through your main panel.
I would think one would know the limit is based upon what the MSP is rated for with the proper main breaker switch for that panel. The "limit" is what it's rated for. Did I not say, "If a panel is rated at 200 amps, THAT IS ITS LIMIT (200 AMPS)?" I'm quite sure I said that.
The "limit" I'm referring to is when someone wants to lower the limits of what the main is rated for by applying the same limitations in the NEC for circuits to Main Service Panels (MSP). I thought I made that quite clear. So, sorry for the confusion by not adding the word, "percentage" limit to my statement. There is no PERCENTAGE limit on your main panel. But still, I thought I made that quite clear with the following statement, "If a panel is rated at 200 amps, THAT IS ITS LIMIT."
I was not talking about if it was in the NEC or not, that is what you were talking about. I am talking about a realistic design where the main panel is sized for the service entrance. You were talking about code, I was talking about reality. The service entrance wires need to be derated. Sure, if you have a 400 amp service and a 200 amp main panel, you might be able to get away with running that panel at 200 amps. The reason I say might is because you will likely trip breakers and might need to derate it due to other conditions such as heat. Running a panel at 100% may or may not be unsafe, but it is certainly not a realistic plan. I have a lot of panels that start tripping once they get to 70%, 100% is never going to happen and isn't a realistic possibility.
So, CODE is NOT reality? LOL REALLY?
If one has an MSP rated at 200 amp with a 200 amp main breaker that is fed by a meter and service cable rated at 400 amps, their 200 amps MSP is actually protected MORE from over heating. If they have a 400 amp service meter and cable rated at 400 amps between the meter and the 200 amp MSP, It simply means they are ready to upgrade their 200 amp MSP to 400 amps if they wish. They are certainly NOT in any danger of overloading a 400 amp service cable and meter with a measly 200 amp MSP. I'll explain in a moment.
Also, if your MSP Main breaker begins to trip at 70%, your main service breaker is a piece of shiznit and needs to be replaced. That's why i go with Square D - QO. They have the best in the business. You're full of shiznit about 100% is never going to happen because I did it several times in the summer to see exactly the amount of rigs I could have running with certain appliances running at the same time in the house. I know the amperage for each appliance and my rigs to KNOW IT IN FACT REACHED 100%. So, stop trying to state something you don't know anything about.
Voltage (Electromotive Force) provides the PRESSURE for current (Amps) to flow. Current (Amps) WILL NOT FLOW
unless the circuit has a load on it. ALSO, the amount of current flowing depends on the amount of load (draw) from the circuit(s) fed by the MSP and the amount of voltage feeding the MSP.
So, if someone has a service meter rated at 400 amps and a service cable between the meter and the MSP rated at 400 amps while feeding a 200 amp MSP, IT DOES NOT MEAN THEY HAVE 400 AMPS FLOWING INTO THE 200 AMP MSP. THAT 200 AMP MSP WILL ONLY BE ABLE TO PUT 200 AMPS OF LOAD ON THAT 400 AMPS SERVICE.... PERIOD! As for your statement,
"...if you have a 400 amp service and a 200 amp main panel, you might be able to get away with running that panel at 200 amps. The reason I say might is because you will likely trip breakers and might need to derate it due to other conditions such as heat."
That statement is incorrect. A 200 amp MSP can only put a maximum load of 200 amps on that 400 amps service. That 400 amps service cable would not even feel warm and certainly would not feel hot. The service rated at 400 amps would simply mean it is less likely to heat up from a 200 amp load on it. Also, a 200 amp service SHOULD have sufficient cable to allow for a 200 amp load without over heating. If it does over heat, IT IS NOT UP TO CODE. 400 AMPS IS NOT FLOWING INTO A 200 AMP MSP, PERIOD, BECAUSE THE MAXIMUM LOAD OF THAT MSP IS 200 AMPS. You have no business trying to teach people what you don't know about.
We have 240 Volts (Electromotive Force) coming into the MSP via 2 cables of 120 Volts on each cable with a neutral in most homes in the U.S. Current (amps) is not flowing in the MSP unless there is a load on a circuit(s) in the MSP. Do you get it now?It seems to me you are using "hand me down" information from a "would be electrician" who is ignorant about MSP's, Electromotive Force and Current.
Even a 20 amps breaker SHOULD trip at 20 amps; not 14 amps (70%) as you say. The same goes for a 200 amp breaker in an MSP rated at 200 amps. It "SHOULD" trip at 200 amps (+/- 2%). If it begins to trip at a percentage further out of that 2% range, one needs to replace that breaker. It is either old, defective or out of specifications.
I have bought 5 x 30 amp/2 poll breakers before and one was defective. It would trip at about 25 amps instead of 30. I had to return it for another 30 amp breaker that would trip where it should (30 amps). It was quite easy for me to tell the amps in the circuit because my PDU's are "metered." It's a good idea to keep spare breakers on hand. When I purchase a spare breaker, I disconnect an existing breaker and install the spare breaker to make sure it trips where it should. If it doesn't, I return it. Otherwise, it's too late to return it when you need it.
The "In addition" was where I was talking about a realistic design where the main panel is sized for the service. I know you did not say you can run more through the main panel than what the service is, I never said you did. That is where the words "In addition" come in. "In addition" means I was building on what you were saying, it wasn't me putting words in your mouth. Relax...
I am relaxed.
I just don't want to hear someone put "limits" on what one's MSP can push and thereby misinform my fellow miners. Nothing irks me more than to hear someone spew out "hand me down" concoctions than are not facts. If an MSP is rated for 200 amps, that's what it can do... 200 amps. And THAT is reality! Do you think all of the engineers who put the NEC together were not in sync with "reality?" Lives and property are at stake. I'm pretty sure they reside well within the realm of "reality." The only part of one's electrical system that should not be allowed to go over 70% [For safety purposes] are circuits within walls and conduit. THAT'S IT... Look at the code... THAT is "reality!"
I sure as hell don't know all there is to know about mining, lines of code, etc. I'm learning each and every day. I find the more I learn there is even more to learn. If I'm not 100% sure, I will tell someone I'm not 100% sure when making a statement. Thereby, leaving the door open for someone with more knowledge and experience on the subject to come in and clarify or make things right. I'm sure as hell not going to pretend I'm a master on the subject and ultimately end up putting a foot in my mouth. This, is in essence, what you have done with your example of supplying a 200 amp MSP with a service cable and meter rated at 400 amps.
By the way, I've taught telephone technicians how to use their meter to identify and locate troubles since 1997 to this present day. I was also a communications electronics center technician in the Marine Corp from 1984 to 1988. I almost went through with getting my master electricians license after getting out of the Marine Corp to start my own business as an electrician. However, I changed my mind after I saw how the BIG competition could easily make a bid lower than mine on jobs. So, I started my own business partnering with my father designing and building training boards that simulate 19,700 feet of 24 AWG/Air Core Cable to teach telephone technicians for several different telephone companies all over the U.S. My father retired in 2010.
My main client now is CenturyLink. I'm the one who actually does the training. I teach service technicians, cable repairmen, outside plant engineers and transmission engineers. We had 6 employees (trainers) at one time. We had to let them all go in 2008 after the crash. Most companies have cut their budgets. Training is one of the first things to go out the window when budgets are cut.
Below, are a couple of photos of a class I taught [And continue to teach] with a photo of one of my many training boards. I normally have 12 to 18 students in each class for 5 to 10 business days. It depends on who I'm teaching and what I'm teaching in regards to the Local Telephone Loop. The gray training boards hook up to a black master board that is also connected to a 48 Volt DC PSU [Not shown]. I'm sharing them with you [Not to brag or boast] to try to emphasize I know what I'm talking about.
https://i.imgur.com/Awb5Wu4.jpghttps://i.imgur.com/fhdjYaR.jpgOh lord, here is another self righteous person who really just misses the point completely...
Again, my post was to clarify where you said "No where in the electrical code will you see a limit on how much you can run your main panel". I simply wanted to clarify that there are limits on how much you can run through a main panel. You probably simply made a typo and said that there are no limits. I read "No where in the electrical code will you see a limit on how much you can run your main panel" as telling people they can run as much through their panel. I was simply making it clear there is a limit to how much you can run through a main panel. I am sure you would agree with this, give me a break and stop being so crazy...
The whole other BS you rant and rave about I couldn't care any less about. Saying "your main service breaker is a piece of shiznit and needs to be replaced. That's why i go with Square D - QO" is just ignorant. I actually only use QOB breakers, they are the ones that sometimes trip at 70%. They are the QO, but better as they bolt on. How is that for them being a piece of shiznit?
I am not going to bother writing more than this at it is just be a waste of time. If you want to discuss the finer points or your teaching (or anything else you feel you need to say to make yourself feel better), just do it over PM and don't waste space on the forum. It is already clogged up with about 99% pointless posts as it is.
