SWITCHES ART 404

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What part of the code that says, switches should switch off all ungrounded conductors? What type of snap switch should be used in a line-to-line system voltage? :confused:
 
Re: SWITCHES ART 404

I'm not sure what your describing

line-to-line system voltage?
You will have to be more specific about the switch application.

230.205(B) requires each service disconnecting means to open all ungrounded conductors.
 
Re: SWITCHES ART 404

I agree with Russ you will need to tell us the application.

Not all applications require the switch to open all the ungrounded conductors.

[ November 21, 2004, 06:54 AM: Message edited by: iwire ]
 
Re: SWITCHES ART 404

Iwire,

What application in the code that does not require to open all ungrounded conductor?

In a 240 volts line-to-line system, switching a lighting load, Is it allowed by the code to use a single pole snap switch? Or should it be a 2poles snap switch since both conductor in a 240 line-to-line is ungrounded conductor?

If this is allowed what provision or exemption article can I possibly find it?

If not allowed what provision in the NEC says that all ungrounded conductors shall be switched off.

Is a snap switch controling the lighting fixture can be considered as a disconnecting means for the lighting? :roll:
 
Re: SWITCHES ART 404

404.2(B) Exception: allows the disconnection of grounded conductors where all the ungrounded conductors are disconnected at the same time.

edit to add
ALSO 410.48 and 410.54

[ November 21, 2004, 08:41 AM: Message edited by: russ ]
 
Re: SWITCHES ART 404

To tell the truth I was thinking there are more places that allow the opening of, less than all the ungrounded conductors. So far I only see 430.84
 
Re: SWITCHES ART 404

Ross,

Your reply on article 410.48 and 410.54 answered my question that all ungrounded conductor supplying a lighting load shall simultaneously disconnect all conductors.

Thanks
 
Re: SWITCHES ART 404

Ross,

However for article 430.84, Where it says Need Not Open All Conductors.

The controller shall not be required to open all conductors to the motor.

Isn't the code refering to the grounded conductor but not to the ungrounded conductors? :roll:

Because in the exception: Where the controller also serves as also as a disconnecting means, it shall open all ungrounded conductor to the motor as provided in 430.111

and 430.111(A) also specifies all ungrounded conductors should be switched off?

What is the intention of the code in article 430.84 in saying that Need not open all conductors to the motors???? :confused:
 
Re: SWITCHES ART 404

Russ,

On Article 404.2 Is just a requirement if somebody wants to switched off a grounded conductor but still ALL UNGROUNDED CONDUCTORS shall be switched off.

Isn't it unsafe if ungrounded conductors are not switched off?
:eek:
 
Re: SWITCHES ART 404

Originally posted by poweringtech:
Iwire,

What application in the code that does not require to open all ungrounded conductor
There is no general provision stating a switch must open all ungrounded conductors, therefore there is no a need for an exception.

There are specific sections relating to specific applications, an example of such would be 410.48 or 410.54.

Or most any place that talks about a switch used as a the 'disconnecting means'.

A switch not used as the disconnecting means is another matter, you could install a single pole thermostat for 240 volt baseboard heat. (424.20(B)), or you could install a single pole switch to shut off the 240 volt heat but it would not qualify as the 'disconnecting means'.

Bob

[ November 21, 2004, 09:55 AM: Message edited by: iwire ]
 
Re: SWITCHES ART 404

Originally posted by poweringtech:
However for article 430.84, Where it says Need Not Open All Conductors.

The controller shall not be required to open all conductors to the motor.

Isn't the code referring to the grounded conductor but not to the ungrounded conductors? :)

[ November 21, 2004, 10:02 AM: Message edited by: iwire ]
 
Re: SWITCHES ART 404

seems I miss read 404.2(B), Thanks

The following is to confirm that I understand what we are all saying.

I agree not opening all the ungrounded conductors is not safe.
Bobs pointed out there is nothing to stop someone from installing single pole controls in certain situations for two pole equipment

As far as lamp holders and Electric Discharge Lamp fixtures if your going to switch them, all of the ungrounded conductors must be opened.
 
Re: SWITCHES ART 404

You may also want to keep in mind the requirement for controls like unit switches to have a marked off position for them to be considered a disconnecting means. The reason is that it is only required to open part of the circuit to keep something from working. For instance, a single pole thermostat could be used on a 240 volt baseboard heater in accordance with 424.20(B). :D
 
Re: SWITCHES ART 404

Hello Charlie,

Just confuse.

Condition:

System voltage is line-to-line 240 volts.

What type of switch do I have to use?

Will the code allow me to use a single pole switch?

Isn't it that single pole switch is only for use in a 240 volts line-to-neutral system voltage?

In circuit breaker article 240 this is the case but I am looking for a specific provision in the code that says that in switching all ungrounded coductors shall be switched off for safety.

I have one of my electrician nearly electrocuted while changing the fixture, because the switch used in a 240 volts line-to-line system is a single pole switch.

Or should this be added in the NEC code.

Thanks
 
Re: SWITCHES ART 404

The following is my understanding and I have not verified this information. If you are disconnecting the equipment, you are required to disconnect all ungrounded conductors. If you are controlling the equipment, you are required to disconnect just enough ungrounded conductors to stop the equipment or the portion that you are desiring to stop. In order to do any work on the equipment, the disconnecting means has to be opened and the lockout/tagout procedures used. Most of the time the control device is also the disconnecting means and is required to open all the ungrounded conductors to qualify as the disconnecting means as well as the control. :D
 
Re: SWITCHES ART 404

poweringtech, Like charlie says, there are disconnecting applications & controlling applications.

If your application is simply a snap switch (light switch) to turn on/off lights that are operated at 240V. (2-hots), by all means use a 2-pole snap switch. Why would anyone do it any other way.
 
Re: SWITCHES ART 404

Hello Kiloamp7 and Charlie,

Charlie says that you dont have to switch off all ungrounded conductor if you are using the switch only as a control.

This means that even if two conductor are hot, the code allows that you can only switch even one of the two hot conductors? Am I right charlie?

While kiloamp says that if the load is supplied by 2 hot conductors the light switch should always be 2pole.

I have to agree with kiloamp7 because there could be a danger of electrocution if for example the light is being replaced and one of the hot conductor is not switched off. Unless the disconnecting means should be switched off first.

Can be a code suggestion wherein if the switch will not open all ungrounded conductors because it is only being used for control, it should be properly marked that it is not a disconnect or for control only.

So that maintenance personnel will not be misled by the switch as the same as the disconnect to prevent accident
 
Re: SWITCHES ART 404

Don't lose the fact that I was shooting from the lip, that is my understanding and I have been found to be wrong. You are correct in your understanding of what I said though. :D
 
Re: SWITCHES ART 404

Originally posted by poweringtech:
Charlie says that you dont have to switch off all ungrounded conductor if you are using the switch only as a control.

This means that even if two conductor are hot, the code allows that you can only switch even one of the two hot conductors?
That is 100% correct in many applications.

Originally posted by poweringtech:
While kiloamp says that if the load is supplied by 2 hot conductors the light switch should always be 2pole.
In the case of a lamp socket 410.48 requires the switch to disconnect all the ungrounded conductors

410.48 Double-Pole Switched Lampholders.
Where supplied by the ungrounded conductors of a circuit, the switching device of lampholders of the switched type shall simultaneously disconnect both conductors of the circuit.
If it is an ballasted type fixture that uses two ungrounded conductors 410.54(B) applies.

410.54(B) Switching. Where supplied by the ungrounded conductors of a circuit, the switching device of auxiliary equipment shall simultaneously disconnect all conductors.
Originally posted by poweringtech:
I have one of my electrician nearly electrocuted while changing the fixture,
What kind of fixture?

Can't tell you if 410.48 or 410.54(B) applies to your particular installation without knowing the details.

Originally posted by poweringtech:
there could be a danger of electrocution if for example the light is being replaced and one of the hot conductor is not switched off.Can be a code suggestion wherein if the switch will not open all ungrounded conductors because it is only being used for control, it should be properly marked that it is not a disconnect or for control only.

So that maintenance personnel will not be misled by the switch as the same as the disconnect to prevent accident
I am not trying to pass the buck however your maintenance personnel bare responsibility for their own safety.

They should never assume;

1) The circuit was wired to code in the first place.

2) The switch / breaker / disconnect functioned properly and all poles opened.

3) That just because the equipment appears to be dead that it is actually dead.

Get your maintenance personnel each a non-contact voltage tester and require that they carry it when ever they are on the clock.

The company I work for requires all the employees to not only carry the non-contact tester but it must be visible on me. :cool:

[ November 22, 2004, 03:10 PM: Message edited by: iwire ]
 
Re: SWITCHES ART 404

Hello Iwire,

Well appreciated. Your explanation was very clear. Article 410.48 and Article 410.54(B) requires all ungrounded conductor to be switched off.

Is there any provision in Art 410-Luminaires (Lighting Fixtures), lampholders and lamps. That says that if a switch is used only as a controller you dont have to switch all ungrounded conductors?

If there is no provision in the code, would it be safe to say that in controlling Luminaires, lampholders and lamps, Switching device should always switch of all ungrounded conductors?

Again thanks all of your comments are well appreciated
 
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