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Cubey
08-16-2007, 07:50 PM
I purchased a breaker box with 2 slots for a project I am working on for a portable outdoor 30 amp to 15 amp converter that features an outdoor breaker box with two 15 amp breakers leading to 2 duplex outlets with an in-use weatherproof cover, raised up off the ground by a stand. I will then plug in 12 gauge extension cords for extra amperage in my vintage travel trailer. This is my solution to the breaker question thread, but now I have a new separate question/problem.

Anyhoo, the breaker box I purchased has the ground and neutral connected together. Is this normal for a sub breaker? Some websites I read say not to do it while others say its normal. Huh??

If its not normal, how do I deal with connecting the ground? Do I splice the outlet's ground to the 30 amp service ground directly without going through the breaker's ground strip (which is very obviously also the neutral connection off to the sides) or what? That certainly doesn't seem right from what I read online since current going through ground has something or other to do with tripping the breaker.

Can anyone clearify if its safe and normal for a sub breaker to have ground and neutral connected together, especially when it's going to be plugged into many different electrical systems. I need to know the universal way to wire the breaker box's ground & neutral in a safe fashion, if that is at all possible.

Cubey
08-16-2007, 08:24 PM
Figured it out for myself finally! Isolate neutral from ground in a sub panel. Looks like I'll be going back to home depot for a grounding bar to put in.

Bob NH
08-16-2007, 09:03 PM
What is a "portable 30 amp to 15 amp converter"? Are you using the subpanel to supply a couple of 15 amp outlets from a 30 amp breaker?

Answers to your question:

The neutral in a subpanel must be isolated from the ground.

The usual practice is to have a ground bar separate from the neutral bar but you probably don't need a ground bar for two circuits (see below).

The neutral bar is often mounted on an insulator and there will be a green screw, installed or furnished loose, that "bonds" the neutral bar to the enclosure. That screw is not used in a subpanel and must be removed if it is already installed.

If the neutral bar is mounted directly to the enclosure (not insulated), then you will have to install an insulated bar for the neutral or provide another means to isolate the neutral.

Then you will have to provide a ground point to connect the incoming and outgoing grounds to the enclosure. That could be a ground screw in the enclosure with the grounds all connected to it.

Are you feeding the subpanel with a two-pole 240 volt breaker or a single 30 amp breaker?

The outdoor receptacles will have to be GFI protected. The best way it to install a

Are you running the wire from the main panel underground? UF or in conduit?

Usual Practice:
The usual practice with a subpanel is to run a 240 Volt circuit (from a 2-pole breaker) to the subpanel. If you want 15 amp circuits you would run #14 black and red (or two black) plus one #14 white plus a #14 green (or a 14-3 + ground cable) to the subpanel. Then you would run two separate #14 circuits (15 amp) to the outlets. You need only #14 because the neutral load cancels if both circuits are loaded.

However, that won't work if the trailer is wired for only a 120 Volt supply.

The way you have described your installation (30 amp circuit to subpanel) you will have to run #10 black, #10 white, and #10 green (or #10 cable such as UF) to the subpanel.

Edit Postscript: You answered your question, a lot more succinctly than I did, while I was writing. I will leave this here in case there is information that may be useful to you.

Cubey
08-16-2007, 10:26 PM
What is a "portable 30 amp to 15 amp converter"? Are you using the subpanel to supply a couple of 15 amp outlets from a 30 amp breaker?

Are you feeding the subpanel with a two-pole 240 volt breaker or a single 30 amp breaker?

Are you running the wire from the main panel underground? UF or in conduit?


It will plug into 30A service at an RV park and there is a 30A breaker on at the hookup pedistal. The purpose of this is so I can make use of the 30A service without using a $5 "cheater" adapter which can be a fire hazard if misused either on purpose or accident.

I need this for long term use however I didn't want to have to haul the trailer to someone to have a hole cut into it for a 30A inlet, nor have to pay that since people around here charge an arm a leg for the most basic things so I figured it wouldn't be cheap.

I'm far from good at simple wood cutting so I didn't dare try to do that myself. This seems like the safest and easiest solution for doing it all myself. I will have that breaker thing to carry around but I don't see that as a big deal. Doesn't weigh much and can be stored easily.

I really only need it when 15a isn't enough, which is what the trailer's electrical system is designed for. I will need the extra amperage mainly in winter when I will need to run a heater or two. This will provide me with safe extra amperage for that. I suspect a single 1500W heater will keep me plenty toasty but I say "or two" since.. well, you never know! A second heater could be run at a lower setting (ie: 600W) as not to max out the hookup. Also, there will only be one duplex outlet per breaker so there definitely won't be any overloading. A single extension cord will be plugged into it and run into the trailer. In the case of needing two heaters I'd have to run another cord as well or just use it on a lower setting while plugged into the trailer's electrical system. As long as I count my amps I'll be fine though I don't wish to put much strain on the trailer's electrical system.

This is actually also useful should I find an RV park or campground that lacks 15/20A outlets. I can haul out my converter and get separated, breakered 15A power without using a cheater adapter.


The outdoor receptacles will have to be GFI protected. The best way it to install a

I was thinking about that but wasn't sure. I guess I will do so.



....

However, that won't work if the trailer is wired for only a 120 Volt supply.

The way you have described your installation (30 amp circuit to subpanel) you will have to run #10 black, #10 white, and #10 green (or #10 cable such as UF) to the subpanel.


Yes, that is what I will do. Home Depot has a #10/2 cable rated for outdoor use (not UF, it was black and insulated) that is flexible and the guy said that would be fine to use for wiring up to a breaker. I will only need about 4-5 feet of this as converter will be kept right at the hookup pedestal and 15A extension cord(s) run to the trailer from it's outlets.

This may seem like a big waste of time an effort when I should just get a 30A system built into the trailer but eh, this seems kind if easier for me so thats what I went with. Easier, except I have to haul out a special convert box every time. Oh well! *lol* I could easily have 30A service put in later and reuse the breaker box and such if I find this to be too much trouble but I don't think it will be for my planned usage of it.

Cubey
08-16-2007, 11:42 PM
Here is a photo of it so far. It will have a big #10/2 (plus ground) cable coming out the bottom of the breaker box of course but this how it'll look aside from that. The purpose of the stand is to keep it from falling forward or sideways. It will be braced against the electric hookup pedestal so it won't be able to fall backwards. A simple $2 lashing strap going around the pedestal and stand will keep it up just fine should there be some gusty winds.

The stand legs are just leftovers from some poles I got used for making a rope & pole awning using a tarp. The stand is clamped in place and mounted to the back of the breaker box with screws & nuts.

The weatherproof in-use outlets are attached to the box via screw in 2" nipple. I need to seal up all the caps and such before I start wiring it up.

http://img.photobucket.com/albums/v222/illiop/portable_30a_converter.jpg

jwelectric
08-17-2007, 05:44 AM
What you have is a death trap in the making. When you get to the RV park find the space that you need.

Cass
08-17-2007, 06:16 AM
Could you expand on that statement.

hj
08-17-2007, 06:53 AM
Either I am misunderstanding, or you made the project more complicated than necessary. It makes no difference whether the park has a 30 amp, or 100 amp at the connection, as long as the wire to your panel will handle it. YOUR breaker in the trailer then limits how much of that power you can utilize. It looks like you have to run an "extension cord" through the door to your subpanel.

jwelectric
08-17-2007, 08:40 AM
What you have is a death trap in the making. When you get to the RV park find the space that you need.Could you expand on that statement.

To understand what is being talked about here one would need to take a look at this thread (http://www.terrylove.com/forums/showthread.php?t=14743) along with the one we are in now.

It seems that this is going to be a Camper used for full time occupancy and more than what the unit is designed for is going to be used at one time.

These campers are set up from the factory with a distribution panel that is designed for the loads in the unit and it seems to me that the owner is wanting to add things that were not originally part of the unit ie; heat and AC.

As has already been pointed out there will be cords passing through floors, walls, windows or doors which is a very big NO, NO!!!


A single extension cord will be plugged into it and run into the trailer. In the case of needing two heaters I'd have to run another cord as well or just use it on a lower setting while plugged into the trailer's electrical system. I will only need about 4-5 feet of this as converter will be kept right at the hookup pedestal and 15A extension cord(s) run to the trailer from it's outlets.

Instead of doing something to help this guy out anyone giving him help is only helping him burn his unit to the ground and I hope no one is inside when this happens.

Cubey
08-17-2007, 12:32 PM
Either I am misunderstanding, or you made the project more complicated than necessary. It makes no difference whether the park has a 30 amp, or 100 amp at the connection, as long as the wire to your panel will handle it. YOUR breaker in the trailer then limits how much of that power you can utilize. It looks like you have to run an "extension cord" through the door to your subpanel.

Thats the thing. The wire between the 15A inlet to the panel is about 14 gauge. The insulation seems to lack any markings but its definitely not 10 gauge. In the 60s trailers came with 15A electrical systems, unlike now where they come with 30A or 50A. It would be a real fire hazard to use a cheater adapter which adapts a 30A outlet to 15A and runs through a 15A extension cord and plugs into a system designed for 15A only.




As has already been pointed out there will be cords passing through floors, walls, windows or doors which is a very big NO, NO!!!

Instead of doing something to help this guy out anyone giving him help is only helping him burn his unit to the ground and I hope no one is inside when this happens.

I guess I'm not understanding the problem with running in an extension cord. Whats the harm?

It will be entering the trailer though a plastic dryer vent. When I removed the gas furnace that was missing parts and generally beyond repair, I first put in a small catalytic heater (which lacks low oxygen sensor so I want to use that sparingly) which requires a high pressure propane supply so I had to run a dedicated high pressure propane hose in so I put in a dryer vent with a hatch next to the entrance door and ran in the propane hose.

I can also use this for running in the extra extension cord. It will have no pressure on it such as a door or window and will not be bringing in any water when it rains. It enters through the dryer vent and into a cabinet. I simply run the cord out of the cabinet and I have the added amperage I need. I don't see how that would be unsafe or a fire hazard.

Here is a photo of the dryer vent with the propane hose entering through it.

http://img.photobucket.com/albums/v222/illiop/dyer_vent.jpg

Seems perfectly safe to to me to do it in this fashion. I will be installing GFCI outlets for the converter and it will be double breakered (the 30A hookup breaker plus my 15A breakers). The box will be kept off of the ground so it won't be sitting in a puddle of water. I guess I'm not understanding the problem. I do see how I've greatly complicated things but my only solution would be to have someone cut the hole in the trailer for the 30A inlet. Seems like nothing in contrast to what I'm doing, I guess. Wish my logic didn't complicate things as it does.. But in any case I honestly don't see how this idea is dangerous. If you feel it is, please explain it.

jwelectric
08-17-2007, 12:44 PM
I don't see how that would be unsafe or a fire hazard.

The biggest danger lies with what you can't see as a danger.

You must first learn that what works is not always what is safe.

The fact that you have changed the heating unit for a high pressure unit is a big danger in and of itself.

Now you are wanting to start adding cords through holes in the wall to add to the current load of the camper.

Unless you are planning on having this camper tested with the remodel work you are doing I would highly suggest that you stop.

Cubey
08-17-2007, 01:34 PM
The biggest danger lies with what you can't see as a danger.

You must first learn that what works is not always what is safe.

The fact that you have changed the heating unit for a high pressure unit is a big danger in and of itself.

Now you are wanting to start adding cords through holes in the wall to add to the current load of the camper.

Unless you are planning on having this camper tested with the remodel work you are doing I would highly suggest that you stop.

It seems you are completely misunderstanding what I'm doing.

Regarding propane, I didn't "change" the pressure from high to low. The original furnace ran on the low pressure propane supply lines. The heater I bought needs high pressure as it was designed for 1lb bottles, but of course can safely run off of a bulb cylinder (kept outdoors, of course!) with the proper hose which is what I have done. The heater is connected to a bulk cylinder located out on the tongue of the trailer and the hose runs in to the heater. It is completely independent of the low pressure system of the trailer which the stove and fridge run off of. Perfectly safe.

Now about the electrical stuff. I will NOT be adding any more load to the trailer's electrical system. Thats why I will be running in an extension cord, for the specific purpose of NOT adding excessive the load to the trailer's electrical system. The extension cord will have a heater plugged directly into it, completely separate from the trailer's electrical system. I will not be overloading anything anywhere. The trailer will have it's electrical system plugged in to one 15A outlet and the extension cord I run in will directly plug into a heater while being plugged into another, seperate circuit 15A outlet. Think of it as plugging in two extension cords on two seperate circuits in a house and using them. Thats bascually what I will be doing, except one of the extension cords plugs into the trailer's electrical system for its original 15A service. The other one will feed a heater. However the extra extension cord is plugged directly into the heater. I will not be combining two extension cords into the trailer's electrical system to pull 30A out of a 15A system which seems to be what you think I will be doing. I will simply be using an extension cord that is run into the trailer for plugging in a heater. I will get a 12 gauge cord so it can handle the load well.

The only other solution I can come up with is to mount a 30A inlet box on the back of the trailer and have the box sticking out of the back instead of being flush on the side. It would be the same thing as I'm doing now except it would be built in. (Not sure why I didn't think of that before...) I suppose I could try to do that but really it would be the same difference as using an outdoor converter. Would mean less cords to deal with is all. Humm.. now I think I may do that. *grumbles* I'm about the worst in the world at making descisions.

jwelectric
08-17-2007, 03:41 PM
Cubey

Once again, What you are doing is building yourself a death trap.

You are taking appliances that are not approved for what you are using them for and trying to install them in a tender box.

The best and only advice I have for you is to either live with what you have or trade it in for something that you want before you kill yourself.

Cubey
08-17-2007, 03:49 PM
You are being very vague. You are not explaining anything. A statement that its a deathtrap tells me nothing about the WHY it is. Anyone can make a statement that something is dangerous but without the explaination as to why it is dangerous, how would anyone understand and not do it? Tell me WHY and WHERE it is dangerous.

And what appliances are you talking about? A heater? Since when is a 1500W heater not supposed to be used on a 15A circuit?

jwelectric
08-17-2007, 04:42 PM
Well let's see how this works out.

It is a resistive heating load that is to be calculated at 125% and I do believe that this will come to 15.625 amps. Now letís add a voltage drop from a drop cord and wonder where it will be?

The NEC is a bare minimum safety rule book and it states;

ARTICLE 400 Flexible Cords and Cables
400.8 Uses Not Permitted.
Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following:
(1) As a substitute for the fixed wiring of a structure
(2) Where run through holes in walls, structural ceilings, suspended ceilings, dropped ceilings, or floors

Should I run into something like you are talking about doing in my jurisdiction there would be a power failure throughout the park in which this was found.

Should a fire start and the insurance people find what you are describing then I doubt very seriously there would be a pay off.

Should a fire start in your unit that caused damage in other units I do believe that you would be held liable.

As to the new gas unit, was it purchased from a RV dealership or off the shelf at the big box store? There are some listing issues that would need to be addressed.

Cubey
08-17-2007, 06:16 PM
Lets look a bit deeper into the NEC code you referred to. You put in bold 400.8 Uses Not Permitted. but you completely ignored the following line: Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following ....

Now lets look at 400.7:


400.7 Uses Permitted

(A) Uses Permitted. Flexible cords and cables must be used only for:
(1) Pendants
(2) Wiring of luminaires
(3) Connection of portable lamps, portable and mobile signs, or appliances
(4) Elevator cables
(5) Wiring of cranes and hoists
(6) Connection of utilization equipment to facilitate frequent interchange.
(7) Prevention of the transmission of noise or vibration
(8) Appliances where the fastening means and mechanical connections are specifically designed to permit ready removal for maintenance and repair, and the appliance is intended or identified for flexible cord connections
(9) Data processing cables as permitted by 645.5
(10) Connection of moving parts
(11) Temporary wiring as permitted in Sections 527.4(B) and 527.4(C)


Take note of number 3 and 6 which I placed in bold.

According to number 3, it says portable lamps, signs or appliances. A 1500W heater is a portable appliance which would allow for flexible cable to be used on it. I would assume that means its power cord but that is what an extension cord is, just an extension of the power cord so that would mean that a long, flexible extension cord is fine to use on a heater. That doesn't really clarify the "though a wall" issue however.

But..moving on to number 6...

According to the list at http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9879 a recreational vehicle is considered "utilization equipment" which would allow flexible cable to be used to "facilitate frequent interchange" as mentioned in NEC 400.7.

What I get from that is 400.8 says you absolutely can't:

(1) As a substitute for the fixed wiring of a structure
(2) Where run through holes in walls, structural ceilings, suspended ceilings, dropped ceilings, or floors

Unless specifically permitted in 400.7, flexible cords and cables shall not be used [for the items listed above]".

400.7 says you CAN use flexible cable for "utilization equipment" and the link above I provided states that an RV is "utilization equipment".

So the NEC code seems to state that its perfectly fine to use flexible cable through a wall.

Also, I found out today that is how they make RV 30 amp inlets. I thought they had a fixed male socket but it turns out they put a #10/2 flexible cable with a male plug inside of a compartment with a hatch cover which is what you plug your 30amp cord into, not a fixed socket like I thought. So your argument kind of just flew out the window about it being dangerous and against NEC code to run flexible cable though a wall. They do it on a daily basis in the US for manufacturing RVs at this very moment and its in keeping with the NEC code.

11 in 400.7 may also apply but I can't seem to locate 527.4(B) and 527.4(C) in the NEC code online.

Speedy Petey
08-17-2007, 07:34 PM
Cubey, MAN, you are fishing, without bait.

Nice try on all fronts but every argument is baseless.

1) Flexible cords CANNOT be run through walls. Regardless of what you think you found you did not find any exemption for this rule. Mainly because there is none.

2) Your "RV cord through a hatch theory" is totally WRONG. This is NOT a cord through a wall. It is a cord through a SPECIFICALLY designed hatch with a notch for the cord.


Over the many years of coming to boards like this has taught me a few things. One of those things is recognizing when someone makes a statement like "Anyone can make a statement that something is dangerous but without the explaination as to why it is dangerous, how would anyone understand and not do it? Tell me WHY and WHERE it is dangerous.". This is almost always an indication that someone is fishing for the answer they want to hear. If they don't get that answer they call foul because they didn't get a full and detailed explanation. Sometimes a full and detailed explanation is quick and easy to put into words. Sometimes a full and detailed explanation is not worth it. Sometimes it can be well over the head of the average lay person.
Sometimes folks just need to be told "DON'T DO IT", "THIS IS DANGEROUS", and they need to simply accept that.
It's not like we are making out on this stuff. It's not like by telling you this our brother-in-law who is an electrician as well is going to get the job.
We say this stuff because we know better, not because we will gain anything from it.
This is why it amazes me when folks question us up and down the block when we say not to do certain things. Sometimes code is just CODE!

jwelectric
08-17-2007, 08:05 PM
Lets look a bit deeper into the NEC code you referred to. You put in bold 400.8 Uses Not Permitted. but you completely ignored the following line: Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following ....

Now lets look at 400.7:



Take note of number 3 and 6 which I placed in bold.

According to number 3, it says portable lamps, signs or appliances. A 1500W heater is a portable appliance which would allow for flexible cable to be used on it. I would assume that means its power cord but that is what an extension cord is, just an extension of the power cord so that would mean that a long, flexible extension cord is fine to use on a heater. That doesn't really clarify the "though a wall" issue however.
Sorry big guy but your thinking is very flawed. There is no relief to allow a cord to pass through a dryer vent for a RV to be found in Article 400.


According to the list at http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9879 a recreational vehicle is considered "utilization equipment" which would allow flexible cable to be used to "facilitate frequent interchange" as mentioned in NEC 400.7.
Yes a RV is allowed to be cord and plug connected but it is also done in a UL approved manner.
The site that you posted also states that an Industrial substations rule 1910.302(a)(1)(vii) but I canít for the life of me remember seeing one cord and plug connected, can you?


So the NEC code seems to state that its perfectly fine to use flexible cable through a wall. No the code clearly states that you can not run a cord through a wall from the outside to the inside to plug in an electric heater.


So your argument kind of just flew out the window about it being dangerous and against NEC code to run flexible cable though a wall. They do it on a daily basis in the US for manufacturing RVs at this very moment and its in keeping with the NEC code. First it is not my argument but the argument of the National Fire Protection Agency that you are trying to buck.
No they donít do it on a daily basis anywhere in the US. What they do in RV manufacturing companies is install a system that has been tested by a third party and install a system that has been approved and listed for the use.


11 in 400.7 may also apply but I can't seem to locate 527.4(B) and 527.4(C) in the NEC code online. There is a very good reason why you canít find 527.4 (C) and it because there is no 527.4 (C).
The Article that governs RV is 551 and 551.44 is the rule for the electrical supply to the RV.
551.44 Power-Supply Assembly.
Each recreational vehicle shall have only one of the following main power-supply assemblies.
(A) Fifteen-Ampere Main Power-Supply Assembly. Recreational vehicles wired in accordance with 551.42(A) shall use a listed 15-ampere or larger main power-supply assembly.
(B) Twenty-Ampere Main Power-Supply Assembly. Recreational vehicles wired in accordance with 551.42(B) shall use a listed 20-ampere or larger main power-supply assembly.
(C) Thirty-Ampere Main Power-Supply Assembly. Recreational vehicles wired in accordance with 551.42(C) shall use a listed 30-ampere or larger main power-supply assembly.
(D) Fifty-Ampere Power-Supply Assembly. Recreational vehicles wired in accordance with 551.42(D) shall use a listed 50-ampere, 120/240-volt main power-supply assembly.

551.45 Distribution Panelboard.
(A) Listed and Appropriately Rated. A listed and appropriately rated distribution panelboard or other equipment specifically listed for this purpose shall be used. The grounded conductor termination bar shall be insulated from the enclosure as provided in 551.54(C). An equipment grounding terminal bar shall be attached inside the metal enclosure of the panelboard.
(B) Location. The distribution panelboard shall be installed in a readily accessible location. Working clearance for the panelboard shall be not less than 600 mm (24 in.) wide and 750 mm (30 in.) deep.

As you can see you have missed it by a long shot.

If you are going to fix the RV then do it right or not at all.

jwelectric
08-17-2007, 08:06 PM
Sorry Petey you posted while I was working, Well put!

Cubey
08-17-2007, 08:07 PM
Cubey, MAN, you are fishing, without bait.

Nice try on all fronts but every argument is baseless.

1) Flexible cords CANNOT be run through walls. Regardless of what you think you found you did not find any exemption for this rule. Mainly because there is none.

2) Your "RV cord through a hatch theory" is totally WRONG. This is NOT a cord through a wall. It is a cord through a SPECIFICALLY designed hatch with a notch for the cord.

This is why it amazes me when folks question us up and down the block when we say not to do certain things. Sometimes code is just CODE!

Baseless?! That is the NEC code! You are the one who brought up the NEC code 400.8 and when I point out what it ACTUALLY says, you argue with the very code you mentioned. You have to be kidding me!! You make an argument and when it bites you in the butt you disregard it? I see how it is. You don't seem to know what in the world you are talking about! Yes, code is code. And the code says its allowed! Thats a code YOU pointed out to ME.

Cables *CAN* be run through walls. The NEC code says it CAN and you just AGREED that it can be when it goes through special hatches or what have you. In the same breath you say that it's never okay to do it no matter what and then say its okay so long as you use special parts. HUH??

What in the world have I already said about running the extension cord into the trailer? It will be going through a dryer vent with protects the opening and plugs from rain. That is exactly what the special RV hatch does. The dryer vent will do one better, the outlet on the extension cord will be far inside of the trailer out of possible wetness!

People who accept things people say without question cannot think for themselves and have no clue about anything. An intelligent mind wants to know WHY something is so. That is called LEARNING. You cannot simply tell someone not to do something without telling them WHY. You do not teach them anything. You merely command them.

Either you are full of it or you simply have a different definition of "running cable through a wall" than I do. I don't wish to simply drill a hole and run a cable through it. I wish to feed an extension cord through a hooded dryer vent (no actual dryer hooked to it!) which protects the opening from rain. Does as good of a job if not better than an RV 30A inlet hatch.

I am arguing with your statement because you are not making any sense what so ever. You claimed it was dangerous and what have you. I ask you why. You say its against NEC code and provide me with 400.8. When I point out what 400.8 says that you skipped over, which says to refer to 400.7 and 400.7 says its ok, you completely disregard the NEC code altogether!

I know an electrician that I will ask about this. I was trying to avoid asking him the favor but it since you are so completely involved in trying to be right no matter what I say will ever be right with you. I have to disregard your argument that completely ignores the NEC code 400.7 that I have pointed out to you.

You have done nothing to help me. All you have done is argue with me and tell me I'm doing it wrong. You have not once actually given me any actual help or advice. You merely criticized me. That is not helpful. That is just rude.

I will post the results of what the electrician says about both running in an extension cord and also the safety of the converter box I built. If he says its unsafe I will figure out something else. However, he will have the decency to explain WHY its dangerous so I don't make the mistake again some day and not just tell me not to do it. If I don't know what I'm doing wrong specifically how can I not do it in the future? Apparently that doesn't matter to you. you just want to order people around and not actually teach them anything.

jwelectric
08-17-2007, 08:16 PM
You have done nothing to help me. All you have done is argue with me and tell me I'm doing it wrong. You have not once actually given me any actual help or advice. You merely criticized me. That is not helpful. That is just rude.
Son neither of us are trying to be rude and both of us are trying as hard as we can to help you. What we can't do is help you if you are not willing to accept what we have to offer.

You are sold on your idea and when someone is as sold on an idea as your are your idea it is hard to get them to stop and see the flaw in their idea.
It is sorta of like telling some that a rose bush has thorns and will hurt them and then they can't see the rose for looking for the thorns.

Leave my house going in any direction and you will pass a RV park within ten minutes. Within a 50 mile radius of my home there are at least 100 RV parks. Yes I have seen a few go up in smoke and one or two explode.

What you are playing with is fire and I hope that you can see this before it is to late.

I am now finished with this thread!

Speedy Petey
08-17-2007, 08:18 PM
Cubey, I don't know who the hell you are talking to but it certainly is not me. At least not all of it.
You quoted me but are going off on a rant about other things. That was my first reply in this thread and I didn't even quote a code section.

I think you are so wrapped up in getting mad at us because you THINK we are "completely involved in trying to be right" that you don't want to hear anything but what you want to hear.

I realize now why I have stayed away from replying in this thread until now. I think I'll go back to staying away.

You have fun with your project and GOOD LUCK!

Cubey
08-17-2007, 08:37 PM
Sorry big guy but your thinking is very flawed. There is no relief to allow a cord to pass through a dryer vent for a RV to be found in Article 400.

If you want to nit pick, the code DOESN'T SAY a lot of stuff. The code is not going to say that because almost no one thinks to do it. Either they are too rich to do any work for themselves and pays everyone to do their work for them and/or they buy a $100,000 RV with 50 amp service. Sorry, but I am not a rich man. I cannot afford a $100,000 RV. Heck I can't even afford a $5,000 used RV. My point is, the code can never give you an example for every possible safe way of doing uncommon things.

If a code specifically says someplace that you cannot run an extension cord from outside to inside then your argument would be completely valid. But so far no one has done this. 400.8/400.7 pretty much knocked down that argument unless someone can provide a link to a code that specifically states that an extension cord cannot be run indoors even through a weatherproof opening in the wall.



The site that you posted also states that an Industrial substations rule 1910.302(a)(1)(vii) but I canít for the life of me remember seeing one cord and plug connected, can you?

Say what? It points out recreational vehicles. How the heck do you think an RV gets its power? By having the electric company come out and hard wire it to the pole every time you pull into an RV Park?


No the code clearly states that you can not run a cord through a wall from the outside to the inside to plug in an electric heater.


Show me where it says that. No, seriously. I want to see where it says that. If you can show me that, I will be wrong and I will apologize to you.



There is a very good reason why you canít find 527.4 (C) and it because there is no 527.4 (C).
The Article that governs RV is 551 and 551.44 is the rule for the electrical supply to the RV.
551.44 Power-Supply Assembly.
Each recreational vehicle shall have only one of the following main power-supply assemblies.
(A) Fifteen-Ampere Main Power-Supply Assembly. Recreational vehicles wired in accordance with 551.42(A) shall use a listed 15-ampere or larger main power-supply assembly.
(B) Twenty-Ampere Main Power-Supply Assembly. Recreational vehicles wired in accordance with 551.42(B) shall use a listed 20-ampere or larger main power-supply assembly.
(C) Thirty-Ampere Main Power-Supply Assembly. Recreational vehicles wired in accordance with 551.42(C) shall use a listed 30-ampere or larger main power-supply assembly.
(D) Fifty-Ampere Power-Supply Assembly. Recreational vehicles wired in accordance with 551.42(D) shall use a listed 50-ampere, 120/240-volt main power-supply assembly.


Finally, someone who actually posts something relevant! That code makes perfect sense and I agree with it completely. However, I'm not discussing installing a second internal electrical system (well, I did mention but but I also didn't want to do it).

I would like to have a portable, external outdoor system that converts 30A to 15A and then an extension cord plugged into 15A runs into the trailer via a dryer vent for running a heater. This involves two entirely different discussions really. One being the running of an extension cord into the trailer while being plugged into an external power outlet, and then about the 30A to 15A converter in itself.



551.45 Distribution Panelboard.
(A) Listed and Appropriately Rated. A listed and appropriately rated distribution panelboard or other equipment specifically listed for this purpose shall be used. The grounded conductor termination bar shall be insulated from the enclosure as provided in 551.54(C). An equipment grounding terminal bar shall be attached inside the metal enclosure of the panelboard.
(B) Location. The distribution panelboard shall be installed in a readily accessible location. Working clearance for the panelboard shall be not less than 600 mm (24 in.) wide and 750 mm (30 in.) deep.


That code seems to just talk about the breaker panel. According to that code I would be following it by using a specifically designed outdoor use power brealer/distribution center in a readily available location, outside. The box is designed for outdoor use for providing breakers/distribution and thats exactly what I wish to do with it. However, that is a completely separate matter than running an extension cord from outdoor to indoor.



As you can see you have missed it by a long shot.

If you are going to fix the RV then do it right or not at all.

No, I haven't missed it. You are talking about doing something entirely different than I am. I'm not adding an electrical system to the trailer. I'm simply running an extension cord into the trailer from an external power source.

Cubey
08-17-2007, 08:52 PM
Son neither of us are trying to be rude and both of us are trying as hard as we can to help you. What we can't do is help you if you are not willing to accept what we have to offer.

You are sold on your idea and when someone is as sold on an idea as your are your idea it is hard to get them to stop and see the flaw in their idea.
It is sorta of like telling some that a rose bush has thorns and will hurt them and then they can't see the rose for looking for the thorns.

Leave my house going in any direction and you will pass a RV park within ten minutes. Within a 50 mile radius of my home there are at least 100 RV parks. Yes I have seen a few go up in smoke and one or two explode.

What you are playing with is fire and I hope that you can see this before it is to late.

I am now finished with this thread!

What causes fires most of all with RVs is people overloading their electrical systems by using cheater adapters which converts a higher amperage outlet to a lower amperage electrical system on an RV (ie: a $5 adapter from Wal-Mart that just changes a 30A outlet to a 15A outlet and thats it).

I am trying to be safe. Thats why I'm even posting on this site! if I didn't care I would use a $5 cheater adapter and hope nothing overloaded. That is NOT what I'm doing here! You talk about fires and such. I'm seeking to NOT overload anything and NOT have a fire. Thats why I built a freaken proper 30A to 15A converter! It amazes me that no one can see this!

I'm trying to find the safest, lowest cost way of handling this but all I have gotten from this site is grief about doing it wrong and no actual advice on how to do it right.

Cubey
08-17-2007, 09:00 PM
Cubey, I don't know who the hell you are talking to but it certainly is not me. At least not all of it.
You quoted me but are going off on a rant about other things. That was my first reply in this thread and I didn't even quote a code section.

I think you are so wrapped up in getting mad at us because you THINK we are "completely involved in trying to be right" that you don't want to hear anything but what you want to hear.

I realize now why I have stayed away from replying in this thread until now. I think I'll go back to staying away.

You have fun with your project and GOOD LUCK!

No. What I want to hear is stuff relevant to the issue at hand. I want people to not act like I'm idiot and actually try to help me, not order me around. When someone was proven wrong they disregarded their original argument. That is just plain aggravating! I wanted help, not criticism.

frenchie
08-18-2007, 12:27 AM
Cubey, FYI? I'm not an electrician, but I know the guy you're argueing with. He teaches code for a living. If he says you're misunderstanding that section... you're probably misunderstanding that section. Chill out & ask him nicely, he might take the time to explain it to you, but get down off that high horse, first. Electricians with decades of experience go to him for help with code interpretation, or "where do I find the section that deals with ____". You do not know the code better than him.

I don't think you understand what "unless specifically permitted" means. In code speak, the key word here is "specifically". There would have to be something in 400.7 that said some kinds of wires could be run through dryer vents, and there isn't.

The interpretation you're using of 400.7, would make 400.8 completely redundant. If I can run an extension cord through a wall for any purpose that I'm allowed to use an extension cord in the first place, there would be no possible situation where I couldn't run a cord through a wall, except situation where I can't use a cord in the first place. Think about it. 400.8 would become meaningless.

As a non-electrician who just happens to live in a northern climate, I'm going to point out the really obvious flaw in your plan: every electric heater I've ever seen, comes with a warning that you shouldn't use an extension cord with it. Oops! Time to switch to plan B.

Mike, Petey - some input on Molo's wire-nut thread?

Cubey
08-18-2007, 01:13 AM
Cubey, FYI? I'm not an electrician, but I know the guy you're argueing with. He teaches code for a living. If he says you're misunderstanding that section... you're probably misunderstanding that section. Chill out & ask him nicely, he might take the time to explain it to you, but get down off that high horse, first. Electricians with decades of experience go to him for help with code interpretation, or "where do I find the section that deals with ____". You do not know the code better than him.

I don't think you understand what "unless specifically permitted" means. In code speak, the key word here is "specifically". There would have to be something in 400.7 that said some kinds of wires could be run through dryer vents, and there isn't.

The interpretation you're using of 400.7, would make 400.8 completely redundant. If I can run an extension cord through a wall for any purpose that I'm allowed to use an extension cord in the first place, there would be no possible situation where I couldn't run a cord through a wall, except situation where I can't use a cord in the first place. Think about it. 400.8 would become meaningless.

I did ask nicely at first but never got a decent response.


Regarding "unless specifically permitted" the code actually doesn't say ANYTHING about any specific kinds of openings in the wall in which you COULD run a flexible cable through. According to you and him that means you can never do it.

Yet the code pretty blatantly says that under certain circumstances such as with "utilization equipment to facilitate frequent interchange" which includes RVs you can do it. 400.8 says that it's allowed depending on certain conditions outlined in 400.7. Pretty sure that, under any sort of logic, means that for RVs you can run a flexible cable through a wall of an RV or other "utilization equipment to facilitate frequent interchange". Plus the fact that they do it on new RVs made in the USA. They use a special hatch/storage place for the hookup on the RV, but..... the code never says that it has to be a special kind of opening. The special openings on RVs are there just because thats the optimal way to do it. In the case of what I'm doing, a dryer vent is the optimal way to do it. Both are plastic, weather proof openings that allow the flexible cable to enter the RV.

Unless the code contradicts itself that means you can run a flexible cable through the wall of an RV with any safe means needed. Weather proofing the hole in which it runs through is just plain common sense. If they added in every possible thing you must do for wiring, the NEC code would be a do-it-yourself guide to electrical wiring. They assume you know how properly and safely run the cable/wire you are installing so that you don't have water coming in the hole in which the cable is running.

Also, I found a site that lists all of the 2005 NEC codes. There is a section (B) of 400.7 not posted up to now in this thread that points out about section 6 of 400.7(A) that states attachment plugs placed on flexible cable is permitted for plugging into an outlet for power. That would mean you can have a flexible cable to plug into an outlet for power according to 400.7(A). 400.8 seems to state that if 400.7(A) 6 is met then running the cable through a wall is permitted according to 400.8.

Again, no where in 400.7 or 400.8 does it say any certain openings in the wall are allowed. 400.8 states that unless specifically permitted in section 400.7 it is not permitted to run a flexible cable through a wall. However, an RV falls under 400.7 sec 6 and therefore is permitted to have a flexible cable with a plug on it run through the wall. But it does not state that it needs any certain kind of opening in the wall anywhere in the code.

Check out the attached image for the 400.7(B) section. I got that from here:
http://www.nfpa.org/freecodes/free_access_agreement.asp?id=
The format in which the site presents the NEC codes via Java doesn't allow copy and paste so that is why I did a screen shot image instead.



As a non-electrician who just happens to live in a northern climate, I'm going to point out the really obvious flaw in your plan: every electric heater I've ever seen, comes with a warning that you shouldn't use an extension cord with it. Oops! Time to switch to plan B.

There is no plan B except completely rewiring the trailer or getting a better gas heater. A gas heater is more likely doable than rewiring the trailer I think unless I could figure out an easy way to add in a 30amp inlet. However according to the people in this thread (mis?)quoting the NEC code, I could never do that even though that is how all modern RVs are. Now do you see why I'm getting annoyed in this thread? According to the folks in this thread, it's against NEC code to even do it the proper way since it would require flexible cable to run through the wall. Sorry, but I'm not the one who is wrong here on the subject of flexible cable running through the wall of an RV. The others in the thread have simply stated flat out its against the NEC code and that is incorrect.

I would have to say that the warning on heaters not to run it on an extension cord is due to the fact that most people would grab their light weight 2 wire household extension cord of about 16 gauge. The power cord on the heater I have is 14 gauge. If someone were to plug that into a 16 gauge cord and run it at 1500W, there is your fire hazard with using an extension cord right there. I plan(ned) on using a 25' 12 gauge extension cord so it will be able to carry the load of a 1500W heater without overloading it since the cord on the heater itself is 14 gauge.

Old Dog
08-18-2007, 06:46 AM
Sorry guys,I just had to jump in!
Cubey,these guys are not picking on you.They are just trying to explain to you the dangers of using extension cords in this manner.As contractors(I'm a G.C.) we have to abide by the codes set forth in the collective trades.You said you wanted to learn so here goes...To put it simply,most codes are born out of trajedy.The reason the codes are there in the first place is because people(men,women,children) have DIED and/or property lost in a similar situation.the codes are there as a guildline for safe practices.These men posting here are concerned for your wellfare.No one said you couldn't do it.They just said you shouldn't do it!They backed up their statements with the appropiate codes.Now if you want to "cherry pick" a few lines in the codes to justify doing it your way thats your choice.
Just do us a small favor...Google "fires started with extension cords."
There are 994,000 examples for you to learn from!(YOU WILL BE AMAZED HOW MANY ARE STARTED WITH PORTABLE HEATERS!!!!)

Bob NH
08-18-2007, 07:52 AM
If I had to do this on an RV I would mount the subpanel to the RV, inside or outside the RV. Then you could connect one circuit from the subpanel to your existing circuit in some legal and safe manner, and the other circuit from the subanel to a duplex receptacle inside the RV. The second circuit could be mounted right off the subpanel enclosure if it is inside the RV.

The input to the subpanel would come from a 30 Amp male connector mounted on the outside of the RV. I'm sure those are available from RV supply houses. http://www.pplmotorhomes.com/parts/rv-electrical-parts-supplies.htm?source=google&gclid=CJLS7K2n_40CFQ8cHgodaV_8PQ

You can work out the details that fit the RV but the logical place to put the equipment is where the power now comes into the RV.

You then have a legal connection both outside and inside. You have increased your capacity inside the RV by adding the second 15 amp circuit with the duplex outlet and you have maintained your existing circuitry inside the RV.

You will have safely increased the total capacity of the RV circuits to 30 Amps with minimal cost.

jwelectric
08-18-2007, 09:50 AM
Bob I almost agree with you except one thing.

The RV is a listed piece of equipment and to alter the electrical system on the inside would alter the listing of the RV.
There a lot of legal issues that occurs when someone alters the listing of a piece of equipment although it is done often.

The use of portable electrical heaters in these RV vehicles is like playing with matches over an open can of gas.
For weight control the walls and cabinets are made from thin wood or plastic components that are easily ignited.

With the use of portable electric heaters the user is going to do one of two things. Either the heater is placed close to the wall where the heat is close to the kindling or cords are used and are either a trip hazard or get covered by something.

Either way there is a hazard involved that shouldnít be in place and violates the rules outlined in 551 of the NEC as well as the UL listing of the RV unit.

Having had dealings with several RV parks in my area I see some nightmares that the weekend DIYer has concocted. I have personally witnessed 100 amp panels, gas cook tops, gas furnaces, (both ran in copper tubing that was damaged from rubbing while being moved) and cords strung all over the place.

Once reported to the management the RV was expelled from the park as a safety hazard.

Now letís donít forget the people who buy RVs to live in full time. I have seen the charred ceilings from kerosene heaters, scorched walls from cooking appliances and the all too common burnt floors from drop cords. But then again, what do I know about electricity?

We have people that have champagne taste but coke-a-cola pocket books that canít see any danger in what they are doing until it cost someone their life. These are the ones that donít have any business owning a RV at all.

A good example of, ďwell it works so it must be alrightĒ from a full time RV owner.

http://i3.photobucket.com/albums/y63/jwelectric/rvcable.jpg

Cubey
08-18-2007, 11:01 AM
Just do us a small favor...Google "fires started with extension cords."
There are 994,000 examples for you to learn from!(YOU WILL BE AMAZED HOW MANY ARE STARTED WITH PORTABLE HEATERS!!!!)

I am doing the search right now. They are all fires caused by overloading the extension cord.

http://www.wral.com/news/local/story/102044/
http://www.ofm.gov.on.ca/ENGLISH/Publications/Press/2005/Jun_28_05.asp
http://www.wacotrib.com/news/content/news/stories/2007/08/17/08172007waccops.html?cxtype=rss&cxsvc=7&cxcat=11
http://www.ul.com/regulators/educational/Fall_DormSafety.pdf

They all say the same thing, the cords were overloaded. They used a cord smaller than the gauge of the appliance.

I appreciate the warning but seriously, in the matter of an extension cord in itself, do you really believe that a 25' 12 gauge extension cord would become overloaded by a 1500W heater with a 14 gauge power cord? I'm looking a real answer here, not just something that agrees with me.

To jwelectric:

I greatly resent the statement about "champagne taste". I'll have you know many people do it because they can't afford the insane rent for an apartment in this country. You can buy a used travel trailer like mine for under $1000, park it at an RV park for under $300 in most cases. Its a cheap way to live. Not everyone can afford the luxuries in this world of the rich. We have to use our brains to get by because we don't have the money to do it for us. Thats why I bought the travel trailer and am working on it myself. I don't have the money to guide me through life with ease. I have to actually learn how to fix things and do it myself. And like I said before, if I didn't care, would I even be posting in this thread at all? And when folks like myself actually try to educate themselves, they just get told "don't do it" with no explanation why.

According to your newest post, the is NO legal/safe solution at all no matter what. It's against NEC code to run in a cord and about "listed piece of equipment". So according to that, the system is what it is and can never be changed. That seems wrong to me. The same would have to go for a mobile home then too since they are pre-manufactured to exact specifications. Changing its electrical system at all would then be illegal according to that statement which somehow doesn't seem right.

Also I wonder if UL listings ever expire with age of a product. A 40 year old RV probably has several things that violate an updated NEC code. Building something in that fashion now would violate the NEC code but do codes work retroactively? Does that mean is dangerous? Probably not. I'm sure many old houses still safe and livable and have things that would not be allowed to be done today as far as wiring. One thing I found interesting is that the NEC code stated that previously multiple electrical systems on an RV was fine but now only a single one is.

In any case I guess I'll return this crap to Lowes & Home depot and just try to make due with the gas heater I have. It lacks low oxygen cutoff so I'll just have to be careful and not leave it on at night.

Of course, I could safely run a small electric heater off of the trailer's electrical system IF i keep it at a low settings (ie: 600W) so it only pulls about 5 amps.

Seems to me, its all about having common sense in what you do. If you overload an extension cord, expect a fire. If you keep a heater too close to stuff, don't be surprised when it ignites. That applies to houses too, not just RVs.

That spliced wiring on the full time RV hookup is just plain bad. I had absolutely no plan to anything remotely like that. Looks to me like they didn't even have the ground wire connected. And that huge knot in the UF(?) wire? Sheesh. I have more common sense than that!

Cubey
08-18-2007, 11:26 AM
If I had to do this on an RV I would mount the subpanel to the RV, inside or outside the RV. Then you could connect one circuit from the subpanel to your existing circuit in some legal and safe manner, and the other circuit from the subanel to a duplex receptacle inside the RV. The second circuit could be mounted right off the subpanel enclosure if it is inside the RV.

The input to the subpanel would come from a 30 Amp male connector mounted on the outside of the RV. I'm sure those are available from RV supply houses. http://www.pplmotorhomes.com/parts/rv-electrical-parts-supplies.htm?source=google&gclid=CJLS7K2n_40CFQ8cHgodaV_8PQ

You can work out the details that fit the RV but the logical place to put the equipment is where the power now comes into the RV.

You then have a legal connection both outside and inside. You have increased your capacity inside the RV by adding the second 15 amp circuit with the duplex outlet and you have maintained your existing circuitry inside the RV.

You will have safely increased the total capacity of the RV circuits to 30 Amps with minimal cost.

Yes, I have considered this but I would either have to have someone professionally cut a hole for the 30A inlet, or mount a box externally on the side of the trailer for the 30A inlet and just drill a hole to run the wire into the wire through.

If not for the newer NEC code saying not to have multiple electrical systems on an RV I could easily add a second system to the back of the trailer and have the inlet sticking out from the trailer. Doing so on the side is probably a bad idea, having something sticking out like that on the street side of the trailer a good several inches. I could mount the inlet on the back and run a very long UF cable to the cabinet with the existing breaker is, and simply add in a second breaker, though that would be a lot of UF cable to have to run. If I knew anyone to do the hole cutting I'd just have them do it. I'd do better to put a new breaker near the back of the trailer and run a long, lesser gauge wire to the existing hookup inlet since the wire would cost less.

Seems to me, I just need to watch **** for a catalytic heater with an oxygen cutoff censor for a low price. Sadly I just missed one for under $150 shipped that normally sells for $230+shipping for the newer version of it.

The catalytic heater I have now is an Colemen one that only has gas cuttoff so if the combustion process stops, it cuts off the gas. No low oxygen cut off sensor. I will simply have to be careful and use common sense with it by leaving a window open while running it and not run it while asleep. A 600W heater run at night should do fine on the trailer's electrical system without overloading it. May not keep me toasty warm but it would certainly keep a complete chill from setting in. A small table top one kept on the dinette table would be safe. No walls would be around it for several feet and it would be off the floor so it can't be tripped on.

Cubey
08-18-2007, 03:17 PM
I have decided to forget about adding any extra electrical stuff to the trailer. Seems to be too much trouble. Even though the coleman catalytic heater I have lacks an oxygen sensor, I do have a battery operated CO detector. If for some reason while I'm in in there and i don't notice the drowsiness and headache (I tend to get that way some days in general) then the CO monitor would go off. Of course that isn't a replacement for common sense in using the heater. It will require at least one window to be open. Also I will only run it while I'm awake and inside the trailer. A small electric heater will be perfetcly safe if kept away far from flammables. Just as safe as in a house. It's all about common sense about safety. If I follow the safety instructions on the heater I should be perfectly fine.

Also, I can safely run an electric heater on the trailer's system at 600 or even 900W in addition to a light (about 0.5A for a 60W bulb) and the RV fridge which uses about 1.5 amps. I could even run it at 1500W (12-13A) if I switch the fridge over to propane and use the battery for lights. If I need to use the microwave or something else large, I will just have to turn the heater off until I'm done using the other appliance. I might end up throwing the breaker at the hookup outside the first few times but after a few times of doing that I'm sure I will get used to it. *lol* I will not enjoy having to go out in the cold to reset the breaker and i will definately remember the next time not to run too much at once, heh.

So I guess that is what I will do. Make due with the 15A system I have as best as possible like I had originally planned to do from the start.

I just figured it would be safe and easy to add in an extra hookup but I see I was greatly mistaken.