View Full Version : Shop electrical panel
02-27-2004, 01:33 AM
This is a Siemens G1224l1125cu main lug panel. It will be used as turned into a 'sub-panel' for re-wire of shop.
Things that I like about this unit are; lots of room for wires, note how lonely the actual breaker/buss bar area looks.
It has knockouts everywhere, even has some funky oblong looking ones use unknown.
Extra buss located away from main breaker area-good for storing extra buss screws I guess:cool:
Remove one buss-bar and ground busses are seperated becoming ground and neutral busses.
Remove two screws and breaker/buss area can be flipped so main power leads can enter from bottom of box.
Can be converted to main/breaker box with additional kit . Not sure if using it as such is 'legal' since shut-off is at service drop/meter combo box .
This unit cost about 32 bucks at lowes, the units I have used in the past are the cheaper 25 dollar ones, but since this is 'my' house I splurged.
02-27-2004, 01:34 AM
Here is a better shot showing the bar that must be removed to convert this box into a sub-panel
02-27-2004, 01:51 AM
If it was a sub in an attached structure it would not need main. If it is an entrance to a seperate building and has more than 6 spaces it must have main.
02-27-2004, 02:09 AM
I *just* got to the Service Entrance part of my studies. What is the advantage or reason for fusing or seperating the nuetral and ground buses?
According to the theory I've gone over, the Nuetral and Ground must be connected at the main panel anyway, although again I haven't gotten into specific wiring practice.
02-27-2004, 10:25 AM
No fusing of neutrals. The bond is at service entrance. Seperate g and N at 4 wire subfeds and that is to keep neutral currents on neutral wires and not on the equipment grounding. I am going to post some stuff here, it all applies but some parts are "why "examples and basic theory.
02-27-2004, 10:26 AM
The panels in separate buildings are not really subpanels as far as code is concerned. They are the service equipment for the structure. You can have a subpanel from the service equipment in each building if you want. Between buildings, section 250.32 applies and if there are metal interconnections between buildings such as water piping, or air lines, or any metal interconnection at all, then you must install an equipment ground wire so if you have a 120/240 system, you would have four wires. The neutral would be separated in each building and a grounding bar would be installed, just like a subpanel. Then the code requires a grounding electrode conductor (GEC) to a grounding electrode (usually a ground rod). The GEC will be connected to the equipment ground bar at each building. This is not to clear overcurrent devices, this is for two reasons. One is lightning, the more important one is to put the equipment ground at the same relative potential as the earth. This is for step potential or touch potential voltages so that what you touch in the building is at the same potential as what you are standing on. Now the tricky part. If you do not have any interconnecting metal between buildings, the code allows you to install three conductors between buildings. When you do this you bond the neutral and ground the neutral just like a new service. Some inspectors think that every panel in a separate building must be treated as a subpanel, but this is not true
02-27-2004, 10:28 AM
(B) With Circuit Conductors. By an equipment grounding conductor contained within the same raceway, cable, or otherwise run with the circuit conductors.
NEC HANDBOOK COMMENTARY;
One of the functions of an equipment grounding conductor is to provide a low-impedance ground-fault path between a ground fault and the electrical source. This path allows the overcurrent protective device to actuate, interrupting the current. To keep the impedance at a minimum, it is necessary to run the equipment grounding conductor within the same raceway or cable as the circuit conductor(s). This practice allows the magnetic field developed by the circuit conductor and the equipment grounding conductor to cancel, reducing their impedance.
Magnetic flux strength is inversely proportional to the square of the distance between the two conductors. By placing an equipment grounding conductor away from the conductor delivering the fault current, the magnetic flux cancellation decreases. This increases the impedance of the fault path and delays operation of the protective device.
02-27-2004, 10:32 AM
Now, about "isolated grounds". There are no such things and there cannot be such things. I know they are out there, and I know some of you make the installation under the guidance of the design engineer, or because the electronic guy said it had to be this way or else. I will repeat, THERE ARE NO SUCH THINGS AS ISOLATED GROUNDS.
You will probably find that there is no particular continuity to what I am about to start on. There is no easy way in 20 words or less to do this. So, lets just start. Section 250.146(D) covers "Isolated Receptacles". This section address the IG grounds and states in part; "The receptacle grounding terminal shall be grounded by an insulated equipment grounding conductor run with the circuit conductors." Let's look at this sentence first. The insulated grounding conductor is to run with the circuit conductors --- How can it do this if it goes to a water pipe, or a separate ground rod someplace?
Next sentence "This grounding conductor shall be permitted to pass through one or more panelboards without connection to the panelboard grounding terminal as permitted in 408.20, Exception, so as to terminate within the same building or structure directly at an equipment grounding conductor terminal of the applicable derived system or service." This sentence tells you where the insulated ground is to terminate. How can it terminate within the same building, on the grounding terminal of the service, or the separately derived system (transformer), if it goes somewhere else?
"Section 250.4(D) (5) Effective Ground-Fault Current Path. Electrical equipment and wiring and other electrically conductive material likely to become energized shall be installed in a manner that creates a permanent, low-impedance circuit capable of safely carrying the maximum ground-fault current likely to be imposed on it from any point on the wiring system where a ground fault may occur to the electrical supply source. The earth shall not be used as the sole equipment grounding conductor or effective ground-fault current path." This section requires a low impedance fault return path. The only way to achieve this is to have the equipment ground wire in the same cable, or raceway with the circuit conductors. You cannot separate current flow and maintain a low impedance, it is impossible. Notice one more thing in the above statement. The fault return is go back to the electrical supply source, not where else.
Where do we ground equipment? And yes, electronic equipment is equipment under the code and must comply with all the rules. I know some electronic people think they are special, and are exempt from certain aspects of the code, but believe me they are not. They must follow the same rules as the rest of us. Section 250.6(D) contains the following statement: "(D) Limitations to Permissible Alterations. The provisions of this section shall not be considered as permitting electronic equipment from being operated on ac systems or branch circuits that are not grounded as required by this article. Currents that introduce noise or data errors in electronic equipment shall not be considered the objectionable currents addressed in this section."
This next section tells us what we are to ground equipment to. Believe it or not, no equipment goes to a ground rod, and no equipment whatever is ever connected to a ground rod to ground it. (Yes, there is an exception for 'supplemental grounds') Section "250.4(A)( (3) Bonding of Electrical Equipment. Non-current-carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected together and to the electrical supply source in a manner that establishes an effective ground-fault current path." The electrical supply source is the system from which the circuit originated, actually the supply neutral.
Remember this statement: When the code requires a piece of equipment to be grounded, it is grounded (bonded really) to the system grounded circuit conductor, the neutral. It is never connected to a ground rod, a water pipe, building steel or anything else. It goes directly to the system grounded circuit conductor. (in the case of delta systems it goes to the grounded service equipment).
Then, we ground the system grounded conductor, the neutral, to earth, no equipment to earth, the system neutral to earth. Stop for a minute and consider where you put all the equipment grounding conductors at home. Most of you wired with Romex and the bare ground is landed directly on the neutral bar in the main service disconnect. Not in a subpanel, but at the main itself. Then you grounded the neutral. Thus all the equipment in you house is grounded to the neutral, just like is supposed to be.
Remember this also, the code requires a low impedance ground-fault return path for fault current. In order to obtain this, we must keep all the circuit conductors and the equipment grounding conductors in close proximity in the same raceway or cable. The is also required in "300.3 (B) Conductors of the Same Circuit. All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord, unless otherwise permitted in accordance with 300.3(B)(1) through (4)."
Everything stays together, including the IG ground.
Section 250.54 allows for what the code calls "supplementary grounding electrodes". Some electronic equipment in the installation instructions require this electrode. Why they want these I have no idea, but some electronic people think that if it isn't connected to earth, then it isn't grounded. They don't understand that the earth is loaded with stray currents from many things, but so be it. These stray currents come from many sources. One is the fact that between your grounding electrode at home the system transformer, there are currents through the earth in parallel with your service neutral. These are a fact of life and how much current depends on a lot of things. Also, you, or your neighbors could have a piece of UF going out to a yard light that has a nick in the insulation. Black or white, it don't matter. Some current is leaking out of this nicked insulation and will find it's way back to the electrical system through the earth. Then there are the installations that now grounded to a ground rod because that is the way they were put in. A good example of these are mall parking lot lights, or any large area lighting. A lot of these have no ground wire to them, they are grounded by way of a rod. If one of these lights develops a ground-fault, the current flow is down the rod, then back to the source through the earth. There are many references in the code that prohibit using the earth for an equipment grounding conductor, but these installations exist by the hundreds. If a ground rod is driven into an area that has any of these conditions, the current will be imposed on the equipment connected to this "isolated ground rod". This creates a shock hazard when touching the equipment grounded this way, and any equipment in the building that is connected to the building grounded system.
Take at least one example: A piece or equipment is grounded to a ground rod to satisfy the electronic people. They insist that the equipment be connected to an isolated ground. The average ground rod will megger well over 100 ohms. But just suppose you are lucky and manage a 10 ohm ground rod. 120 volt divided by 10 means that leas than 12 amperes will flow in case of a ground-fault. Will this clear a 15- or 20-amp overcurrent device? No way, but there is 120 volts going down the rod, and 120 volts on the metal of the equipment, just waiting for someone to come in contact with it. Where is this current going from the ground rod. Pretty much where ever it wants, and if there is a swimming pool nearby that for some reason wasn't properly bonded, or has a bad bonding connection, this could be time for an electrocution. About the overcurrent device, in order to clear a standard 20 amp circuit breaker in a reasonable time, it must have close to 80 to 100 amperes pass through it. Kind of hard to do when the rod will only pass 10 or 12 amperes.
I strayed, back to 250.54. This section permits a supplemental grounding electrode at the equipment, but the electrode must be connected to the equipment grounding conductor in the circuit to the equipment. A lot of mall lighting is installed this way. The supplemental electrode is bonded to the equipment ground of the light, and it provides added safety for lighting hits. A lot of the lightning energy will dissipate down the rod. Otherwise it would go back on the equipment ground in the circuit and since the insulation is only 600 volts, it causes a lot of damage to conductors.
02-27-2004, 10:34 AM
For replacement of non-grounding-type receptacles with grounding-type receptacles and for branch-circuit extensions only in existing installations that do not have an equipment grounding conductor in the branch circuit, connections shall be permitted as indicated in 250.130(C). C) Nongrounding Receptacle Replacement or Branch Circuit Extensions. The equipment grounding conductor of a grounding-type receptacle or a branch-circuit extension shall be permitted to be connected to any of the following: (1) Any accessible point on the grounding electrode system as described in 250.50 (2) Any accessible point on the grounding electrode conductor (3) The equipment grounding terminal bar within the enclosure where the branch circuit for the receptacle or branch circuit originates (4) For grounded systems, the grounded service conductor within the service equipment enclosure (5) For ungrounded systems, the grounding terminal bar within the service equipment enclosure If you use the water pipe, the connection must be within 5 feet of where the pipe enters the building.
You are permitted to replace a two-wire nongrounding type receptacle with a GFCI under the following in section 406.3 (3) Nongrounding-Type Receptacles. Where grounding means does not exist in the receptacle enclosure, the installation shall comply with (a), (b), or (c). (a) A nongrounding-type receptacle(s) shall be permitted to be replaced with another nongrounding-type receptacle(s). (b) A nongrounding-type receptacle(s) shall be permitted to be replaced with a ground-fault circuit interrupter-type of receptacle(s). These receptacles shall be marked "No Equipment Ground." An equipment grounding conductor shall not be connected from the ground-fault circuit-interrupter-type receptacle to any outlet supplied from the ground-fault circuit-interrupter receptacle. (c) A nongrounding-type receptacle(s) shall be permitted to be replaced with a grounding-type receptacle(s) where supplied through a ground-fault circuit interrupter. Grounding-type receptacles supplied through the ground-fault circuit interrupter shall be marked "GFCI Protected" and "No Equipment Ground." An equipment grounding conductor shall not be connected between the grounding-type receptacles. When you make this change be very, very careful that you get the hot "black" wire on the right side of the outlet
02-27-2004, 10:57 AM
Ok! Thanks Sberry, I didn't have time to read it but I'm reading every word later on. No worse than what I've got in front of me in Practical Electrical Wiring!
Excellent explanation. I know this is a softball, but hit it out of the park anyway. When I connect a 230 volt machine, I have two power legs and another wire. Normally this is referred to as an ungrounded connection, so I am assuming that it must be a neutral wire. But I have also seen this connected as a ground wire. The line 1 and line 2 connection points were obvious, but the only hookup that was left was a green ground screw. Should I put a white wire connected to a neutral bar on it, or should I hook up a green ground wire connected to a ground bar?
02-27-2004, 12:18 PM
S maybe we should explain the difference between a Neutral (white) and the Mechanicle Ground (green) wires, in terms of what they do.
The neutral wire carrys the imbalanced current between the 2 120 volt sides of the 240 volt circuit back to the transformer, or voltage source.
Imbalanced current occurrs when one side of the line draws a load of 10 amps, and the other side draws a load of 7 amps (example) resulting in an imbalance of 3 amps. If you were to put a meter on the neutral wire you would actually see a 3 amp current.
When inductive loads, such as magnetic flourescent ballasts, are on the circuit there will actually be readable voltage to ground on the Neutral wire.
The mechanicle ground is there to carry any fault current to ground for safety purposes.
Prior to 1964, mechanicle grounds were virtually completely ignored in electrical work (romex only had 2 wires). The arguments about grounding and bonding Earth Ground to Neutral have been ongoing since then, and while a lot of progress has been made, there is a long way to go.
Many, if not most mechanicle ground systems leave a lot to be desired when it comes to being a true earth grounding system, because water services are routinely employed to provide the ground.
02-27-2004, 02:08 PM
If you only have white wire available tape of paint it green. These welding machines do not use neutral. In a main entrance service panel the ground wire goes to the neutral bar,, or equipment ground bar,,, which at main entrance is bonded together. On a 4 wire subfed panel it gets landed on the equipment grounding bar, N and G are seperated in subs. If you havwe an outbuilding that is fed with only 3 wires it gets landed on neutral bar. Neutral as Franz talked about is a current carrying conductor and does have some voltage on it,, its insulated, if it was to be interupted or opened it would have 120V on it. The green or bare grounding wire is not a current carrying conductor except in the event of a fault (short to ground or case of equipment) It is a mechanical bond back to the panel to insure a seperate path allowing for enough current to pass to trip a breaker.
While on the subject, I have been told if I add on to my shop It will have to be brought up to code and if they know a welder will be used there all outlets,plugs and or enclosures within x number of feet from point of use will have to explosion proof. what tha...
02-27-2004, 04:59 PM
There is one whole hell of a lot of forced code compliance going on in this country and at least 80% of it is pure bullsnot being foisted off under the color of authority by pissants working for local government. The pissants have learned they can get away with anything most of the time by merely telling people something.
Always insist that they show you the printed code requirement.
As far as electrical equipment within x number fo feet of a welder, that is pure unadulterated Bullshut. Welders are NOT explosion hazards.
02-27-2004, 10:56 PM
Who told you that? No explosion proof stuff needs to be in welding area. If it is existing you dont need to change it. I agree with Franz,, ask just where is that written?
In my county, you have to drive two grounding rods, no closer than six feet apart , to ground your main service panel. That is not what the NEC book states. Your are also required to have a ground lug in a plastic ceiling box used for lighting. This is also not in the NEC book. The county next to us will not allow the use of 4/0, 4/0, 2/0 Al Triplex for home service installations. You must use 4/0, 4/0, 4/0 Al Triplex. How can these counties insist on having residents and electricians in their areas do things that are not in the codebook? I keep getting told something about a final convening authority. What's that and why is this allowed?
The NEC is not a requirement (law) itself, but it is a standardized set of guidelines. Most municipalities implement NEC with ammendments. Last I checked, here in Dallas, they were still on NEC 1996, plus their ammendments. (NEC is updated every 3 years) They sell copies of the whole thing for hardly any money. It is a pain that the codes are implemented differently from place to place, but in the big picture, the differences are generally very minor, since they're based on NEC.
02-29-2004, 12:41 PM
The main reason codes are interpeted differently in different jurisdictions is because the people making the interpitation are pissants with authority. Most of the inspectors couldn't cut it for 5 minutes as an electrician's helper, so they take their inadequicy on people who can make a good living as electricians.
I've fought too many inspectors whe were counter men in a supply house till they got hired as an inspector, and usually won the argument.
These bozos want multiple ground rods driven, even though they don't employ, or require ground resistance testing, and the end result is ineffective ground systems.
As to 4/0 triplex, are they NUTS? How many services are being installed that have that kind of ampacity? In this part of the country #2 triplex is the standard up to 400 amps of service. Triplex by the very fact that it is hanging in open air has phenominal ampacity. It sounds like some petty pissant bureaucrats have misread something, and are making their jurisdiction "safe".
02-29-2004, 01:20 PM
I keep being told this and that,,, by who???? I think you are listing to tavern opinions. The ground rods thing IS in there. I would want to see any local amendments in writing if this is causing you some concern. They can modify code for local conditions and they often do for earth grounding especially in dry climates. Sometimes there is only so much you can do. The code states you are allowed 1 ground rod if you can prove less than 25 ohms, and if you want to test fine,, but if you cant make 23 you must drive another rod. Way easier to just put 2. Article 250.53 thru 250.56 I think you may heve the dfination of Triplex confused. Tri is for overhead not down the entrance pipe. 4/0 is for service drop.
02-29-2004, 01:41 PM
Local inspectors love to make up regulations on the fly, and foyst them off on people who don't know better. I have yet to meet one who knows shut about ground arrays!
Interestingly, overhead sign structures on interstate highways are required to undergo ground array testing while residential ground systems only require that the local halfwitt inspector look at them.
Bottom line, if your a$$ is dependant on the ground functioning, it better be done right, and a big part of doing it right is metering the array. When I meet the first "inspector" with a ground resistance meter, I'll listen to his opinion.
02-29-2004, 03:18 PM
I heard a good one last night. The guys says,, "I know what I am doing and I about electrocute myself sticking my jacknife in a 480 panel" I told him "impossible" He says,, well it happend. I said, Its impossible to use "I know what I am doing" and "I stuck my jacknife in a 440 panel" in the same sentance. Franz,, my point with the last post was did an inspector actually tell Dog this or was it hearsay?
02-29-2004, 04:53 PM
S, one of the great regretts of my life is that I stopped a lawyer from sticking his Cross pen onto a 480 volt lug many years back.
To make a long story short, there were 6 lawyers in the switchgear room and I was paid to remove covers so they could examine the gear where a dopey ******* made his fingers look like overcooked hotdogs, cause he was sure wearing rubbers made him safe from getting electrocuted.
That was a time of great concern to me, having to decide was I out of splatter range if the fat lawyer did jam his pen onto the lug, cause I sure as hell had no intention of giving him CPR.
I had told all of them, and since none of the lawyers gave me any paperwork stating they had a hearing imparement, I saw little reason to remind them. I also wasn't going to become part of the ground path.
As to the above question of who is telling who what, I have no idea. I sure wouldn't be surprized to hear any inspector make a totally stupid statement though. I believe they have to take a course in stupid to get the jobs.
02-29-2004, 07:51 PM
I have never had much problem with inspectors. My jobs look right and that helps when they figure you are not trying to pull something half assed. We have one in the area now that gives a lot of homeowners a hard time over little stuff,, he has some deal with contractors that he wants to see his buds make out like fat rats I guess. My neighbor did his house and he quoted some nonsense and we didnt argue the point and put a 5$ wire in that made him happy and it wasnt worth a pissing match. On one of my own he ask my helper who was here at the time, "who did this?" He said,, the guy that owns it and he green stamped it and headed out. It was kind of complex enough that he was trying to see if I had help on the side I guess but my helper said he was here for about 30 seconds and hit the trail. The reason I ask about who said what was that I hear plenty of code quoted,,, My brother in law is a maintance man at the local plant and he says,,,, that type of thing. Over all I have had good luck with inspectors and found some of them to be quite helpful actually.
02-29-2004, 11:15 PM
Originally posted by Sberry
Now, about "isolated grounds". There are no such things and there cannot be such things. I know they are out there,
The correct terminology is Single Point Gounding. Rarely utilized in the truest form except in the high end digital world where there is a blend of DC powered equipment and the need for AC plugs as well. The grounding is isolated in "zones", as in IGZ. The AC plugs also have provisions for an isolated ground plug. The orange plugs you may have seen are of that type.
As you say, there is no such thing as isolated grounds. In fact it is extremely impotant that they all be tied together, but in a certain way. We often use a series of "ground bars", each one for the tieing together of specific types of equipment. Single Point Grounding with Isolated Ground Zones. Definately rarely used. Likely never in the home application unless someone wants to put in a computer leg in an equipment shop where there may be spikes, sags, surges or high freq problems.
03-01-2004, 12:16 AM
I guess I caught our inspector on a good day. My service comes in to a 200 amp main box on a pole about 140 feet from my house. The house had a 100 amp panel installed by error. So I got another 200 and put it in line before the house panel. In the new box is a 100 amp breaker that goes to the house and another 100 that goes over to my shop. There is a ground rod at the panel on the pole and I asked the inspector if I should have one at the panels at the house. He said technically there should probably be one there but if he didn't see it he really didn't care. I do have a ground in the underground conduit to the house. I have another grounding rod I haven't used yet. After all I have been reading here I am wondering if I shouldn't go ahead and install it at the shop since it is a seperate structure and I have another panel out there.
Another thing, he told me I should get some lights in a shed I had because he wanted to come help me work on my motorcycle, and I told him, Yeah, then you guys gotta come and give me grief about that. He said, No, lots of things get done that they don't really look at too much, just make sure it looks safe.
03-01-2004, 01:28 AM
Each seperate structure requires a ground rod. You want to dissipate a lightning strike if possible at that point instead of carrying it back on the electric system where the voltage of the wire is limited to 600,, lightning is thousands. Also it is to keep the potential of the equipment you have the same as the ground you are standing on, there could be a few volts difference. Kind os simplified,, but,, yes,, each structure needs rod.
I don't think I'm picking up any bad info at a tavern. I sell electrical equipment and supplies and my comments and requirements that I listed were gleaned from the electricians and home owners who frequent my business. If I hear of a new code requirement that I don't believe or can't make sense of, I personally go down on my day off to our regional building inspectors and ask them . Unhappy customers who are told the wrong info don't come back. Our area has the requirement for two ground rods because of the soil conditions here. The requirement for a grounding lug in the ceiling box is based on the possibility of a person using a metal pull chain switched light fixture. The inspectors have the authority under the code to make such requirements. Franz, I have to assume that you missed the AL (for Aluminum) in my post regarding ampacity of 4/0 Triplex. If not, please consult Table 310.15(B)(6) Conductor Types and Sizes for 120/240-Volt, 3-Wire, Single-Phase Dwelling Services and Feeders. SBerry, I checked the five rolls of 4/0 AL TRIPLEX that I have in stock right now and they have the same thing on the label. They are Southwire brand, so I cannot profess to state what other wire manufacturers might call theirs, but it is called triplex by General Cable and by Southwire. It is a tri rated wire with those being USE-2, RHH, and RHW-2. And no, it can't just be used overhead (as an example USE-2 stands for underground service entrance). Check section 338.2 for verification. Termination requirements can be found in 338.10 (4). A very interesting discussion of neutral sizing can be found in your current 2002 NEC codebook. Our County decided to go with the traditional method, the one next to us decided to err on the side of caution and require that the neutral be the same size as the other wires. They have this right under the code and that is the rule in their area. I serve five counties and have to remember the individual rules for each when I am helping customers. One thing I have learned in life is to not try to impress an inspector with my knowledge of the codebook or on anything else. If I have a beef with his ruling (which I seldom do), I call up his boss or drop by and let them educate me why they want it done that way. I then pass this info on to my customers so they don't get hassled for some new requirement or interpretation. I live in a major population center and can assure you that our inspectors are up on their knowledge (don't even think of applying for a job there unless you have at least a current journeyman's license and years of experience). Of course, things could be different in other parts of the country.
03-02-2004, 02:02 AM
I know this is a softball, but hit it out of the park anyway. When I connect a 230 volt machine, I have two power legs and another wire. Normally this is referred to as an ungrounded connection, so I am assuming that it must be a neutral wire. But I have also seen this connected as a ground wire. The line 1 and line 2 connection points were obvious, but the only hookup that was left was a green ground screw. Should I put a white wire connected to a neutral bar on it, or should I hook up a green ground wire connected to a ground bar? How can these counties insist on having residents and electricians in their areas do things that are not in the codebook? I keep getting told something about a final convening authority. What's that and why is this allowed?
Triplex refers to a wire assembly consisting of 3 conductors and isnt because it is "tri rated". Often triplex is slang for 2 insulated conductors and a bare messenger grounded conductor for overhead entrance wire. It would be called quadraplex if it was 4 conductor. If they are not allowing de-rating the neutral for alum they wouldnt for copper either. Art 310 does not rate triplex, they are rated as single conductors that may be "triplexed together"
Now I did confuse a couple of these threads and didnt realize they were written by different guys and was refering to the thing about explosion proof for welders,,, but,, the above quotes do speak for themselves somewhat.
Sorry if you are getting confused as to who you are talking to. I posted the question about wiring receptacles when I thought one of your earlier answers might cause confusion among those not acquainted with electrical practices. Hence the softball analogy. If you check previous posts, you will find that Franz stated that they use 2/0 AL Triplex in his area for 200 amp service. I gave a table in the NEC codebook that showed that he was mistaken. As were the comments about 4/0 AL Triplex being used only for overhead service. That was also incorrect.(again giving the appropriate codebook section to back it up) I stated that it was tri rated and then gave the ratings. Unless English is a second language to you, most would understand that tri means three. Since I gave the three ratings that are stamped on 4/0 Triplex wire, I thought it seemed appropriate. Sorry if I caused any confusion. I have a character flaw in that I have problems with incorrect electrical practices/information being put forth on the Internet . On most subjects this is not a serious problem, however in area of electrical installation, this can result in expensive mistakes being made in wire selection and installation. Not to mention the possibility of fire or death from incorrect installation of components. The disdain that some hold electrical inspectors in is not conducive to the main purpose of their jobs, keeping us safe from improper installations . Sorry if my style of asking questions to help clarify ideas purposed by others causes you to doubt my intelligence or knowledge of the subject.
03-02-2004, 12:50 PM
ACTUALLY, Franz stated that #2 triplex is used in this area for 200 amp services.
Triplex carrys the same current capacity as single wires in open air.
03-02-2004, 12:57 PM
It makes a difference where the wire is going. Franz was refering to service conductors in open air like the power company uses. You are certainly correct about the use of 4/0 coming down the pipe to the meter base. The 3 ratings stamped on the wire are the insulation ratings for individual conductors. The Triplex stamped on the wire is a brand thing,, similar to Romex or Kleenex. 310.11 A single wire with several,, or lets say 3 ratings on the wire wouldnt be triplex. It would be a single conductor with insulation ratings that fall under 3 classes. If you can find the word Triplex in the code I would be glad to read it.
03-02-2004, 01:08 PM
S, you don't want to know how long it's been since I looked in a Code Book.
03-02-2004, 03:16 PM
.S, you don't want to know how long it's been since I looked in a Code Book. In this part of the country #2 triplex is the standard up to 400 amps of service. Triplex by the very fact that it is hanging in open air has phenominal ampacity.
Yes, I kind of figured as much when I read the post,,, hahahahahahahahahahqa,,, but I knew what you meant. None of my stuff was really aimed at Dog. I got his post confused with the one about the explosion proof and the welders. The thread was long and it was on different pages and the way he posed the ground/neutral question/post kind of threw me for a loop. It was just something for guys to keep in mind when they hear refrences to codes being quoted. Half of it is basic logic,, wire an explosion proof to a machine that makes big sparks??? Even if I didnt know anything about it you can figure it doesnt make a lot of sense. There was one on the other board where the insp had told the guy it was code for a welder recept when it would depend on which machine he was to put on it. The insp actually was doing the guy a favor and probably found it easier to say it was code than to explain why it might br a good idea for him to do it that way. Sounds like even though it wasnt a code thing the insp was looking out for the best interest of the guy and he knows the guy aint going to make a stink,, so, I buy that. Kind of like using a main lug panel as serv entrance,,, legal but not always a good idea. Like I said before,, I really dont have much issue with them guys as long as they are not tryng to enrich themselves at the public trough,, if they want to do that go into biz, not where they are sposed to be public servant
03-02-2004, 03:20 PM
Kind of like welding code book,, I cant ever remember opening one of those. Bout all I know about that is keep the rod hot and when its thick heat it first,, ha But, It dont mean when they put the joint in front of me I cant weld it.
03-02-2004, 05:13 PM
Since we already took this thread over the river, past grannys, and around the clothesline, I'll just mention if anybody needs any Pile National pin type plugs there is a guy selling off a bunch of them on another board.
vBulletin® v3.8.7, Copyright ©2000-2013, vBulletin Solutions, Inc.