Flexible Cable for Generator

[W@ttson]

Hello,

Flexible cable is typically used for connection to roll up 3 phase generators. The connections are either made with Cam locks or pin and sleeve connectors. Typically the inlet is located on the outside of the building, making for a quick connection into the buildings electrical infrastructure. The client would like the cam lock connection to be on the inside of the building. This poses a conflict with Art 400.12 (2) or (3). No matter how, this flexible cable will need to pass through an opening in the building, whether its a doorway, window, hole in the wall, sleeve, etc.

It is being proposed to have an access opening created inside the front wall of the building with a locked door (something like a 18"x18" port). When needed to connect the generator, the door is unlocked and opened. This creates access to the inside. The wall is 20" thick. There may or may not be a sleeve on the inside.

How can the above be compliant with Art 400.12?

If the opening is made bigger and two locked doors are put in, one on the outside and one on the inside, and a piece of non-metallic cable tray is placed inside the wall access block out, will that help things? For example in this situation, the flexible generator cable would just be laid in the cable tray.

Thank you.

 

[W@ttson]

I think by the lack of responses sums things up.

There is no code compliant way to put a generator inlet indoors, since no matter how, you will need to run cables through the building in violation of 400.12.

 

[infinity]

I think by the lack of responses sums things up.

There is no code compliant way to put a generator inlet indoors, since no matter how, you will need to run cables through the building in violation of 400.12.

I don't have the book with me but isn't there something in Article 590 temporary installations that would allow the use of the cords?

 

[rafaelrobertson]

Hello,

Flexible cable is typically used for connection to roll up 3 phase generators. The connections are either made with Cam locks or pin and sleeve connectors. Typically the inlet is located on the outside of the building, making for a quick connection into the buildings electrical infrastructure. The client would like the cam lock connection to be on the inside of the building. This poses a conflict with Art 400.12 (2) or (3). No matter how, this flexible cable will need to pass through an opening in the building, whether its a doorway, window, hole in the wall, sleeve, etc.

It is being proposed to have an access opening created inside the front wall of the building with a locked door (something like a 18"x18" port). When needed to connect the generator, the door is unlocked and opened. This creates access to the inside. The wall is 20" thick. There may or may not be a sleeve on the inside.

How can the above be compliant with Art 400.12?

If the opening is made bigger and two locked doors are put in, one on the outside and one on the inside, and a piece of non-metallic cable tray is placed inside the wall access block out, will that help things? For example in this situation, the flexible generator cable would just be laid in the cable tray.

Thank you.

I've been using 10/3 Romex to go from my generator to the main house panel, but it's a pain to coil up and roll out when I need it. I'm thinking about replacing it with something like welders cable, but since that's a fine-threaded copper wire, I don't know if I need to go larger or what? I'm only using about 50'. Any suggestions are appreciated.

 

[augie47]

Take a look at 590.4(H)... (Credit in infinity )
That Section addresses cords thru doorways so apparently for temporary installs it's permissible.
I have seen installations as you described with a passageway for cables

 

[tom baker]

I've been using 10/3 Romex to go from my generator to the main house panel, but it's a pain to coil up and roll out when I need it. I'm thinking about replacing it with something like welders cable, but since that's a fine-threaded copper wire, I don't know if I need to go larger or what? I'm only using about 50'. Any suggestions are appreciated.

10-4 SO cord to amp inlet.

 

[W@ttson]

Take a look at 590.4(H)... (Credit in infinity )
That Section addresses cords thru doorways so apparently for temporary installs it's permissible.
I have seen installations as you described with a passageway for cables

I had reviewed Article 590 and 590.4(H). I don't think it is applicable.

590.3 Time Constraints.

A = During period of construction
B = 90 Days in reference to holiday lights
C = Emergency and Tests - I don't think a pre-planned generator inlet can be considered an emergency situation. There is a choice to be put outside and therefore not be in conflict with 400.12, it is chosen to be put inside, causing the issue. I see C being applicable where lets say a tree falls down on your incoming service equipment and you run a line to the input of the main panel. Not a pre-engineered roll up generator hookup scenario.
D = Removal, talks about that it needs to be removed immediately.

 

[zbang]

The way 590.3 is written gets me to
If you're doing construction, then you can leave it for the duration.
If you're using it for "holiday lights", then you only have 90 days (should be 30 IMHO).
For tests, experiments, and developmental work, you're allowed (and no time limit is specified).
Nothing in there seems to apply a time limit other uses.

As for "through the doorway", Augie covers that.

 

[Fred B]

With electrical installation the customer is NOT "always right". Why does the customer what the connections inside, instead of normal location?

 

[mtnelect]

When the customer becomes the "Electrical Inspector" it's time to move on.

 

[winnie]

What is the reason for wanting the connection 'insider'? Can you make the connection inside enough for the customer's purpose, yet still outside enough for code?

For example, what if the connection is made inside of a free standing enclosure (say with an open bottom), behind a locked panel door. Say one of these:

https://www.automationdirect.com/adc/shopping/catalog/enclosures_-z-_subpanels_-z-_thermal_management_-z-_lighting/enclosures/floor-mount_enclosures/sce-604808lp

That could be on the outside of the building, but the generator can loks are behind a locked equipment enclosure door. The flexible cords are not passing through a wall, but the connection is still effectively 'inside'.

If the customer wants more weather protection, place this sort of cabinet in an alcove. No additional external door, but under a roof.

The point is that you can give the customer what they want without creating a code violation.

Jon

 

[mtnelect]

What is the reason for wanting the connection 'insider'? Can you make the connection inside enough for the customer's purpose, yet still outside enough for code?

For example, what if the connection is made inside of a free standing enclosure (say with an open bottom), behind a locked panel door. Say one of these:

https://www.automationdirect.com/adc/shopping/catalog/enclosures_-z-_subpanels_-z-_thermal_management_-z-_lighting/enclosures/floor-mount_enclosures/sce-604808lp

That could be on the outside of the building, but the generator can loks are behind a locked equipment enclosure door. The flexible cords are not passing through a wall, but the connection is still effectively 'inside'.

If the customer wants more weather protection, place this sort of cabinet in an alcove. No additional external door, but under a roof.

The point is that you can give the customer what they want without creating a code violation.

Jon

I have learned through the years of contracting to be very concerning before accepting each project. Having the customer becoming the electrical inspector is a major "Red Flag" and should not be taken lightly. This is an indication that the customer will be running the project, and to expect rough sailing ahead.

 

[brantmacga]

I don’t understand why it needs to be inside. If security is an issue, use a lockable enclosure for the cam locks.


Sent from my iPhone using Tapatalk

 

[W@ttson]

The way 590.3 is written gets me to
If you're doing construction, then you can leave it for the duration.
If you're using it for "holiday lights", then you only have 90 days (should be 30 IMHO).
For tests, experiments, and developmental work, you're allowed (and no time limit is specified).
Nothing in there seems to apply a time limit other uses.

As for "through the doorway", Augie covers that.

I would have to disagree. Time constraints are what allow you to use chapter 5 methods instead of chapter 3. If it weren’t for the time constraints outlined, all other times would need to be performed with permanent wiring methods.

 

[W@ttson]

With electrical installation the customer is NOT "always right". Why does the customer what the connections inside, instead of normal location?

Yes, I agree. However, it’s our duty to guide them in the right direction. By no means will this be performed against the code without AHJ approval.

 

[W@ttson]

What is the reason for wanting the connection 'insider'? Can you make the connection inside enough for the customer's purpose, yet still outside enough for code?

For example, what if the connection is made inside of a free standing enclosure (say with an open bottom), behind a locked panel door. Say one of these:

https://www.automationdirect.com/adc/shopping/catalog/enclosures_-z-_subpanels_-z-_thermal_management_-z-_lighting/enclosures/floor-mount_enclosures/sce-604808lp

That could be on the outside of the building, but the generator can loks are behind a locked equipment enclosure door. The flexible cords are not passing through a wall, but the connection is still effectively 'inside'.

If the customer wants more weather protection, place this sort of cabinet in an alcove. No additional external door, but under a roof.

The point is that you can give the customer what they want without creating a code violation.

Jon

Funny enough we have proposed all of these solution. Still a no. The main point of concern is extreme corrosive air (added the extreme for dramatic effect).

Since they aren’t budging on not putting the cam loks inside; we are working on if this is actually 100% against NEC to put inside. They are ready to go through the process of getting a waiver from the AHJ but it is a very time consuming process, and before they embark on it, they want to be sure there is no angle to be played such that the connection point is inside and still be NEC complaint. I need to be able to 100% convince myself before I can fight for an angle.

I even looked at using TC-ER cable. It’s an industrial installation but there are still support requirements which are not practical when connecting to a generator.

 

[W@ttson]

I have learned through the years of contracting to be very concerning before accepting each project. Having the customer becoming the electrical inspector is a major "Red Flag" and should not be taken lightly. This is an indication that the customer will be running the project, and to expect rough sailing ahead.

It was smooth sailing up until now. Certain people just got involved and the waters have gotten rough.

 

[W@ttson]

I don’t understand why it needs to be inside. If security is an issue, use a lockable enclosure for the cam locks.


Sent from my iPhone using Tapatalk

Corrosive air phobia.

 

[zbang]

I would have to disagree. Time constraints are what allow you to use chapter 5 methods instead of chapter 3. If it weren’t for the time constraints outlined, all other times would need to be performed with permanent wiring methods.

Well.... that's not necessarily what the words say. (Many of us think that 590 is rather badly drafted.)

It's helpful to apply Charlie's Rule of Technical Reading--

It doesn't say what you think it says, nor what you remember it to have said,
nor what you were told that it says, and certainly not what you want it to
say, and if by chance you are its author, it doesn't say what you intended
it to say. Then what does it say? It says what it says. So if you want to
know what it says, stop trying to remember what it says, and don't ask
anyone else. Go back and read it, and pay attention as though you were
reading it for the first time.
Copyright 2005, Charles E. Beck, P.E., Seattle, WA

Reading it again-- 590.3(A) permits temporary connections for maintenance and (C) for emergencies with no stated time constraints on either. 590.4(H) indicates that cables may pass through doorways if protected from damage. What's the issue? (I'm looking at the 2017 code.)

Also, applying one of the rules of rhetoric, because there's a time constraint an a single paragraph (holiday lights) you can not assume/apply that exception to the others (otherwise, construction temp could only run for 90 days). (See https://en.wikipedia.org/wiki/Exception_that_proves_the_rule)

All that said, it's extremely common for generator cables to be routed through doorways for short-term use and AFAIK no one has had an inspector complain about it.

 

[W@ttson]

Well.... that's not necessarily what the words say. (Many of us think that 590 is rather badly drafted.)

It's helpful to apply Charlie's Rule of Technical Reading--


Reading it again-- 590.3(A) permits temporary connections for maintenance and (C) for emergencies with no stated time constraints on either. 590.4(H) indicates that cables may pass through doorways if protected from damage. What's the issue? (I'm looking at the 2017 code.)

Also, applying one of the rules of rhetoric, because there's a time constraint an a single paragraph (holiday lights) you can not assume/apply that exception to the others (otherwise, construction temp could only run for 90 days). (See https://en.wikipedia.org/wiki/Exception_that_proves_the_rule)

All that said, it's extremely common for generator cables to be routed through doorways for short-term use and AFAIK no one has had an inspector complain about it.

Exactly. Reading that section you will see the times temporary wiring is allowed. It allows if for construction (construction time frame being the time constraint) and during emergencies (the emergency being the time frame). I never said it’s only 90 days for anything other than holiday lights, take a look at my responses, each one quotes the section directly.

If you are saying that since it doesn’t say that is not permitted at other times, that it is actually permitted all the time I think that is wrong.

The first 3 chapters of the NEC determine what is to be done ALL the time. The rest of the chapters where they specifically alter the requirements of the first 3 chapters then permit leniency.

The only angle can be if this can be designated an “emergency”. This is an optional standby system. By losing power no one is going to lose their life. If a standby system is provided the infrastructure to create the hookup has the ability to be put outside. If there is a chance to be put outside then there would be no violation or need to use the exceptions found in 590.

In other words, if you are designing and installing infrastructure that you would only use at a time of power outage, you are pre planning this, when the power outage happens, it’s not an emergency, it’s an event you have planned for and have the infrastructure in place to power things on an optional standby fashion.

An emergency would be something like a tree falling on your service equipment and you need to make temporary connections to your power distribution equipment. I don’t think “temporary” connections, i.e. article 590 connections can be made on infrastructure designed to accept generator power during a power outage. It is not an emergency at that point.

Emergency is not defined in the NEC so we need to take what the common definition/understanding for it is. This is the definition of emergency:

Def1: “a serious, unexpected, and often dangerous situation requiring immediate action.”

Def2: “ an unforeseen combination of circumstances or the resulting state that calls for immediate action”


As far as inspectors having an issue with running generator wires indoors, I can’t comment on that. As you point out it’s not what you want the NEC to say but what it says. If perhaps this technical reading is pointed out to inspectors, maybe more would have issue?