Working Hot

[flashlight]

It's pretty unanimous that circuits SHOULD be deenergized before tapping.

In the cases where they can't be, I think split bolts are a tedious and dangerous way to go. (There was a full thread on split bolts recently)
I've been trained in the precautions, equipment, etc. but older I get, would rather not.

Does anyone have a lot of experience with Blackburn insulation-piercing taps ?
We use them in temporary situations where POCO is going to come in and redo things. How do they perform as a permanent splice ?

 

[iwire]

Then how do utility companies get away with it ?

Different rules, OSHA rules are very different for line people then for all others.

The death (or should I say 'killed on the job') rate is also much higher for line people than electricians.

Some utilities have their own limits, one near me will only 'glove work' 15 KV and below. Anything above that they shut down and ground out.

Kind of pain as they have ares of local distribution at 39 KV.

 

[iwire]

Worth at least a read considring the topic.

1910.333(a)(1)

"Deenergized parts." Live parts to which an employee may be exposed shall be deenergized before the employee works on or near them, unless the employer can demonstrate that deenergizing introduces additional or increased hazards or is infeasible due to equipment design or operational limitations. Live parts that operate at less than 50 volts to ground need not be deenergized if there will be no increased exposure to electrical burns or to explosion due to electric arcs.


Note 1: Examples of increased or additional hazards include interruption of life support equipment, deactivation of emergency alarm systems, shutdown of hazardous location ventilation equipment, or removal of illumination for an area.


Note 2: Examples of work that may be performed on or near energized circuit parts because of infeasibility due to equipment design or operational limitations include testing of electric circuits that can only be performed with the circuit energized and work on circuits that form an integral part of a continuous industrial process in a chemical plant that would otherwise need to be completely shut down in order to permit work on one circuit or piece of equipment.


Note 3: Work on or near deenergized parts is covered by paragraph (b) of this section.

 

[rbalex]

When I served, the basic philosophy adopted by the 70E Technical Committee was: "If you're going to work on something energized, it had better be because its more dangerous not to." Inconvienience or loss of production expense were not to be considerations.

Utilities are something of a special case because the consequences of a broad area shutdown aren't always well known, even with a planned shutdown. But most production or operating facilites can predict the affects of a planned shutdown with a high degree of accuracy.

 

[dbuckley]

Hot sticks, good gloves, and a lot of training.

And solid procedures. And then even more training, and then learning from what goes wrong, and improving the procedures to make sure it doesn't happen again.

I get scared stupid when I see the utility guys manhandling MV lines atop the poles, but the company is required to publish by law what injuries they are responsible for, and last year for my local POCO none of these wiremen suffered for keeping my lights on.

It's interesting enough I'll quote from the report:

MPNZ suffered six employee incidents during 2008. Four of these were strained backs incurred during lifting and normal work. One was a thumb crushed between a truck and a pole and the last was a notified incident where a lines mechanic suffered injuries to his ribs and a punctured lung when a pole he had climbed broke off at ground level and fell to the ground.

Additional training in good lifting practice has been undertaken since these events occurred, and a pole inspection check sheet has been developed to
show staff how they should identify a pole in poor condition prior to climbing it.

MPNZ also had one public incident on the network system where a customer received an electric shock following a transformer pole replacement job caused by a vehicle accident. MPNZ staff had inadvertently failed to make a connection between a service neutral and the main transformer neutral point. Dual livening signoff procedures have since been developed to help prevent this from reoccurring.

MPNZ now maintains certification to NZS 4801 in health and safety management and as part of this MPNZ is focussing on bringing about change in:
* the safety culture of employees,
* the way that near misses are reported, and
* the management techniques employed by the managers of MPNZ.

The only acceptable target for health and safety incidents for MPNZ remains zero incidents.

I'm sure (or at least hope) all POCOs in the civilised world work the same way with the same goals.

 

[Don S.]

We have used the insulating piercing taps for several permanent 480V installations on wire as large as 500MCM with no problems. They do not look like they could carry the current for which they are rated, but apparently do just fine. They are the modern replacement for split bolts, particularly where you would like to make a hot tap, but being older and wiser, you are no longer enthused about digging into a live wire with your skinning knife.

 

[flashlight]

We have used the insulating piercing taps for several permanent 480V installations on wire as large as 500MCM with no problems. They do not look like they could carry the current for which they are rated, but apparently do just fine. They are the modern replacement for split bolts, particularly where you would like to make a hot tap, but being older and wiser, you are no longer enthused about digging into a live wire with your skinning knife.

Don, thanks, I'm a convert.

 

[flashlight]

We have used the insulating piercing taps for several permanent 480V installations...

What are other good ones besides blackburn ?

 

[zog]

We have used the insulating piercing taps for several permanent 480V installations on wire as large as 500MCM with no problems. They do not look like they could carry the current for which they are rated, but apparently do just fine. They are the modern replacement for split bolts, particularly where you would like to make a hot tap, but being older and wiser, you are no longer enthused about digging into a live wire with your skinning knife.

Just older, if you were wiser you would not do any live taps

 

[flashlight]

Just older, if you were wiser you would not do any live taps

With respect, in some places, if you want to fit your job description, it is necessary.

 

[infinity]

Hang on, every time I bring up the safety aspect I get slammed for being too 'preachy'.:roll:

The fines may be a joke but the total cost to a company after a true accident is very high and it is only the fear of those costs that will change how middle managers make decisions about what can and cannot be shut down.

If you can show them the costs to shut down are more than the costs not to shut down you have a chance.

Bob's right the fines are no joke but I find that people still work live everyday because the rate of accidents and fines is extremely low. If you calcualted the number of guys working hot everyday vs. the number of accidents you would find that most live work is done successfully and without incident. I'm not condoning the practice, just saying that it happens everyday because like it or not many find the risk of injury very low.

 

[hardworkingstiff]

Had PoCo disconnect service conductors to a CT cabinet on Monday. UG service from a 3-phase transformer (fairly large, you can get into the cabinet). Service man was by himself. I walked over to check on his progress and found him inside the cabinet wearing sunglasses ("safety glasses" according to the service man), hard hat and gloves. He was unbolting the service conductors from the transformer secondary buss. I questioned him on if entering the cabinet by himself with no one else around was SOP for Progress Energy. He said he can do it on the load side of the transformer just not on the line side.

Seemed a bit lax to me, but..... what do I know?

 

[WorkSafe]

I would have to look in my books about the electrical generation and transmission side of the house, but I do know I would cite the employer for having their employees working on hot equipment when the equipment could have easily been locked/tagged out. It would be difficult to convince the inspector or ALJ that you could not have de-energized the circuit. If all else fails, they would cite you under the good ole 5(a)(1) of the Act. The only reason they may not cite you for it is if the de-energizing of the circuit adversely effects the health of the public.

5(a)(1) shall furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees;

Mark

 

[zog]

I'm not condoning the practice, just saying that it happens everyday because like it or not many find the risk of injury very low.

Ok, so only a few dead or severly burned electricians is OK?

 

[zog]

Had PoCo disconnect service conductors to a CT cabinet on Monday. UG service from a 3-phase transformer (fairly large, you can get into the cabinet). Service man was by himself. I walked over to check on his progress and found him inside the cabinet wearing sunglasses ("safety glasses" according to the service man), hard hat and gloves. He was unbolting the service conductors from the transformer secondary buss. I questioned him on if entering the cabinet by himself with no one else around was SOP for Progress Energy. He said he can do it on the load side of the transformer just not on the line side.

Seemed a bit lax to me, but..... what do I know?

Funny thing is the arc flash hazard is mots likely much greater on the load side than on the lone side. POCO workers are about to get a rude awakening with the new arc flash rules in the NESC that just came out. That practice will change soon enough.

 

[infinity]

Ok, so only a few dead or severly burned electricians is OK?

Not that I said that, but if you asked the average electrician who works on energized things he will tell you that in his opinion the chances of getting hurt are slim. Statistically I would agree with him. One dead or injured electrician is one too many but IMO you won't find statistical figures to prove that this likelihood of getting injured is great.

 

[neutral]

Ok, so only a few dead or severly burned electricians is OK?

So, do we stop driving our vehicles because people get killed in them every day?

do race car drivers stop racing because a few get killed every year?

If you want to be totally safe you need to find a different job. Every job comes with some risk, thats why you need training to understand the risk and how to work safe and hope you don't have a wreck along the way.

 

[zog]

So, do we stop driving our vehicles because people get killed in them every day?

do race car drivers stop racing because a few get killed every year?

If you want to be totally safe you need to find a different job. Every job comes with some risk, thats why you need training to understand the risk and how to work safe and hope you don't have a wreck along the way.

That is such a stupid response, you have the choice de-energize. To work live you need to justify it and use an EEWP assesing the hazards. I gaurantee 99% of electricians have no idea how to assess the hazards, which is why the new labeling requirements are so key to provide that info.

 

[zog]

Not that I said that, but if you asked the average electrician who works on energized things he will tell you that in his opinion the chances of getting hurt are slim. Statistically I would agree with him. One dead or injured electrician is one too many but IMO you won't find statistical figures to prove that this likelihood of getting injured is great.

They are slim but there are 2,000 arc flash victim sent to burn units each year and 1,200 fatal electric shocks of electricial workers each year. Those are some big numbers, and they are nearly all preventable.

 

[JFletcher]

The rating of the circuit or its OCPD does not really tell you anything about the available fault current and the size of the fireball. You could easily have 1000 amps of fault current on the load side of a 20 amp breaker.

Several years ago I was installing a sconce light. I made the connections, tested the fixture and switch - all I had left to do was install the threaded rod through the box tie bar, level the fixture and put the retaining nut and cover on. I didn't turn the power back off:

Twist, twist, twist, twist.... *CRACK* *BLAM!!*


The tip end of the threads cut through the hot wire in the box. The hollow rod acted like a minature cannon, and blasted small chunks of burning metal into my wrist. Good thing my face wasn't near the box. The 20A breaker never tripped, even with with a dead (low resistance) short to ground. Until that day, I never knew 120V could be so... spectacular. And that was just off of a "little" 12ga wire.

"There are occaisions where I wouldn't even take a cover off without deenergizing"

Agreed. Story for another time.