Using Breakers as Switches.

[bphgravity]

Is the process of opening a breaker or disconnect considered "live work" and thus requires PPE. For example, if an electrician is planning on working on a certain piece of equipment, shouldn't that worker have PPE on before opening the disconnecting device?

My concern is for untrained workers whom are required to turn breakers on and off as normal start of day and closing procedures. One particular location I have recently been to actually opens the main to a 175 ampere lighting and appliance panelboard to turn off lights and equipment at night.

What are the safety procedures required for this? Is there not a hazard doing this without proper training and some sort of PPE?

 

[pierre]

Re: Using Breakers as Switches.

That is an interesting question.

Can you imagine new employee training for opening and closing a store.
"Okay now you have to slip into this suit when you come open the store, when you leave tonight do not forget to put this suit on"

I always thought of this from an electricians perspective.

 

[celtic]

Re: Using Breakers as Switches.

Originally posted by bphgravity:


My concern is for untrained workers whom are required to turn breakers on and off as normal start of day and closing procedures.

That doesn't sound "normal". Normal would be hitting "Stop" Switches.
CB shouldn't be used as switches, unless listed and marked as such: 240.83(D)

Originally posted by bphgravity:
One particular location I have recently been to actually opens the main to a 175 ampere lighting and appliance panelboard to turn off lights and equipment at night.

very abnormal.

What kind of place is this?

 

[bphgravity]

Re: Using Breakers as Switches.

Believe it or not, this has been at a McDonalds, a Books-A-Million, and a Regal Cinemas. None of these locations have typical wall switches to disconnect lighting and various equipment. At the McDonalds, there is actually a shutdown procedure list on the panelboard instructing what breakers are to be turned off at closing and then turned back on at opening.

At the book store, I noticed a similar list on a panel for the cafe area. This list at one time instructed which breakers to shut off at night. At some point, someone scratched out the breaker numbers and posted a new sign with the words, "leave all breakers on! Turn off main switch marked here!" There is a red arrow pointing to the 175 ampere main.

 

[charlie]

Re: Using Breakers as Switches.

In NFPA 70E, CB or fused switch operation with covers on is a Hazard Risk Category 0 Area and requires untreated cotton and safety glasses.

 

[petersonra]

Re: Using Breakers as Switches.

I would say that a lot of places use the panelboard cbs to turn the overhead lighting on and off. As long as the cbs are rated for it, I just don't see it as especially hazardous. It's such a common practice that if it was dangerous someone would have been hurt by now. I don't see it as any more dangerous than truning a common light switch on/off.

Now, switching a main CB is different. I would not be overjoyed with that being used as a light switch.

 

[ron]

Re: Using Breakers as Switches.

Charlie,
An analysis would have to be done if there wasn't 25 kA short circuit current available with 0.03 second (2 cycle) fault clearing time.

For power systems with greater than the assumed short-circuit current capacity or with longer than the assumed fault clearing times, a flash hazard analysis shall be required in accordance with 130.3.

 

[templdl]

Re: Using Breakers as Switches.

There is not a problem with using beakers as switches. But as the breaker gets larger the number of operation as allowed by UL489 decreases.
Assuming that the "175a" breaker is actually a 225a frame the endurance test require 4000FL operations and 4000NL operations @6/min. After the endurance the the?breaker must again pass calibration test.
Keep in mind that the UL test are most likely much more difficult than those you would commonly find in the field.

 

[kencybart]

Re: Using Breakers as Switches.

To bphgravity and company,
It is my understanding that as long as there is no "exposed" live parts, all you need to shut a breaker or fusible switch OFF, is to observe the Shock Protection boundaries of NFPA70E and wear some voltage rated gloves.

 

[petersonra]

Re: Using Breakers as Switches.

Originally posted by kencybart:
To bphgravity and company,
It is my understanding that as long as there is no "exposed" live parts, all you need to shut a breaker or fusible switch OFF, is to observe the Shock Protection boundaries of NFPA70E and wear some voltage rated gloves.

I have to ask this. Why would it be any more hazardous to open/close a 120V CB at a typical panelboard to turn the lights on/off versus a typical light switch? is this just a sign of someone going overboard on safety requirements and not thinking?

 

[bthielen]

Re: Using Breakers as Switches.

I can't help but think that OCPDs have a purpose and "controlling" lighting circuits is not one of them, is it? The more the cbs are operated the greater the odds of failure due to wear. It would seem that it would be better to use a switch to do what it is designed to do and a cb to do what it is designed to do.

Bob

 

[templdl]

Re: Using Breakers as Switches.

bthielen,
There is not a problem with using beakers as switches. But as the breaker gets larger the number of operation as allowed by UL489 decreases.
Assuming that the "175a" breaker is actually a 225a frame the endurance test require 4000FL operations and 4000NL operations @6/min. After the endurance the the breaker must again pass calibration test.
Keep in mind that the UL test are most likely much more difficult than those you would commonly find in the field.