70e questions

[mickeyrench]

Can any worker open or close or reset a breaker in the main switch gear or do they have to be trained and wear ppe for that ? 480 volts.

 

[cornbread]

Can any worker open or close or reset a breaker in the main switch gear or do they have to be trained and wear ppe for that ? 480 volts.

Trained.. yes. IMHO.

PPE is another question, at our plant we require PPE be worn for all 480 volt switcggear operation.

 

[billsnuff]

Anyone inside the arc flash boundary is required to wear PPE. That requires a given level of training.

Anyone inside the remaining (limited, restricted, prohibited) approach boundaries requires training, must be a 'qualified' individual, with appropriated PPE.

At what point is the equipment put in an electrically safe condition?

 

[zog]

According to the NFPA 70E, a ?Qualified Person" is one who is trained and knowledgeable of the construction and operation of the equipment or the specific work method, and be trained to recognize the hazards present with respect to that equipment or work method.

Such persons shall also be familiar with the use of the precautionary techniques, personal protective equipment, insulating and shielding materials, and insulated tools and test equipment. A person can be considered qualified with respect to certain tasks but still be unqualified for others.

An employee that is undergoing on the job training and who, in the course of such training, has demonstrated the ability to perform duties safely at his or her level of training and who is under the direct supervision of a qualified person shall be considered to be a qualified person for the performance of those duties.

In addition, to be permitted to work within the limited approach of exposed energized conductors and circuit parts the person shall be trained in all of the following:
Qualified employees shall be trained and competent in:
The skills and techniques necessary to distinguish exposed live parts from other parts of electric equipment
The skills and techniques necessary to determine the nominal voltage of exposed live parts
The minimum approach distances specified in this section corresponding to the voltages to which the qualified employee will be exposed, and,
The decision making process necessary to determine the degree and extent of the hazard and the personal protective equipment and job planning necessary to perform the task safely
A few notes to add to the 70E definition.
Only the employer can deem an employee qualified after they have had the proper training and have demonstrated profinency using the skills and method learned.
There is no such thing as NFPA 70E certification, going to a training course does not make an employee qualified.
The most misunderstood part of the "qualified" term is that it is all emcompassing, you are "qualified" to work on a specific type or piece of equipment.
Neither a J-card, a masters license, or an engineering degree make you a "qualified person"
The word "electrician" is not anywhere in the definition of a "qualified person" meaning these rules apply to all employees and you dont have to be an electrician to be "qualified"

 

[richxtlc]

For the opening and closing of a breaker, I agree with what has been posted, but as for resetting a breaker the rules change. You can reset a tripped circuit breaker if you know the cause of the trip, e.g., motor tripped due to a jam, the jam was cleared. If the cause of the trip is unknown, then you cannot reset the circuit breaker until you have determined the cause of the trip. If you close into a fault, the circuit breaker may fail on the second fault and cause even more damage or trip the backup protection and you lose even more equipment then was lost on the initial outage.

 

[zog]

For the opening and closing of a breaker, I agree with what has been posted, but as for resetting a breaker the rules change. You can reset a tripped circuit breaker if you know the cause of the trip, e.g., motor tripped due to a jam, the jam was cleared. If the cause of the trip is unknown, then you cannot reset the circuit breaker until you have determined the cause of the trip. If you close into a fault, the circuit breaker may fail on the second fault and cause even more damage or trip the backup protection and you lose even more equipment then was lost on the initial outage.

Good point Rich, this is actually an OSHA requirement that not many people are aware of.

1910.334(b)(2)"Reclosing circuits after protective device operation." After a circuit is deenergized by a circuit protective device, the circuit protective device, the circuit may not be manually reenergized until it has been determined that the equipment and circuit can be safely energized. The repetitive manual reclosing of circuit breakers or reenergizing circuits through replaced fuses is prohibited.

Note: When it can be determined from the design of the circuit and the overcurrent devices involved that the automatic operation of a device was caused by an overload rather than a fault condition, no examination of the circuit or connected equipment is needed before the circuit is reenergized.



That means for a INST, ST or GF trip on a breaker, or if you have a breaker that does not give you indication of the cause of the trip you need to isolate the circuit and megger the downstream circuit to determine if it is safe to re-energize.