Originally Posted By: jmichalski This post was automatically imported from our archived forum.
OK, this has very little to do with actual home inspections, but I just recommended replacement of a badly worn and damaged service entry cable from the mast to the meter. The buyer understood the recomendation but asked how they (licensed electricans) go about doing this without getting electrocuted.
I know I should probably know this, but never having personally repalced one nor even witnessing it, I am not certain. I would imagine it requires special equipment? Is there some method for cutting the power at the feeds while making the replacement
Just curious - I was embarrased not to know, but I never asked before....
Originally Posted By: jmichalski This post was automatically imported from our archived forum.
OK, Jeff, so that begs the question: How do they work with live wires? (handling by the insulation and relying on that for protection?) I am really curious as I have never seen it done and I have a healthy respect for electricity. I can’t imagine trying to secure a live cable to a panel or splice.
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
Insulated gloves and experience!
If we hadn't run Bob off he would have more to add to this.
It is common for old sparkies to hook up the service drop, usually using Romex Connectors in the splice, until the PoCo gets back to crimp them.
The PoCo always works 120/240 hot and usually even the medium and high voltage stuff. You just have to be careful and know what you are doing, using the right PPE.
Originally Posted By: James D Mosier This post was automatically imported from our archived forum.
When my service panel and meter box needed replaced the electrician left the meter out while connecting the service wires (to eleminate the chance of current flow) and worked one wire at a time and one handed as much as possible on a fiberglass ladder.
Originally Posted By: tallen This post was automatically imported from our archived forum.
James D Mosier wrote:
When my service panel and meter box needed replaced the electrician left the meter out while connecting the service wires (to eleminate the chance of current flow) and worked one wire at a time and one handed as much as possible on a fiberglass ladder.
Did he use the proper PPE??
Gloves, rated tools ect.?
-- I have put the past behind me,
where , however, it now sits, making rude remarks.
Originally Posted By: dandersen This post was automatically imported from our archived forum.
I live in a rural area and are fortunate to have one to two houses per transformer. In the event of ice storm damage or repair, they just pull a big switch at the pole!
This comes in handy when your neighbor has trees all over the power lines. They shut him off and turn the rest of us back on!
There is a lot of this type of service at overhead configurations in the city as well.
I could never change out a panel or drop live!
I would be afraid to go Oops!
Originally Posted By: wdecker This post was automatically imported from our archived forum.
In Commonwealth Edison (Chicago area) country, you schedule the power company to disconnect the power, at the mast, the change out the SE. If you give the power guys a six pack, they will wait and hook it back for you. Only takes an hour if you know what you are doing.
Originally Posted By: James D Mosier This post was automatically imported from our archived forum.
tallen wrote:
James D Mosier wrote:
When my service panel and meter box needed replaced the electrician left the meter out while connecting the service wires (to eleminate the chance of current flow) and worked one wire at a time and one handed as much as possible on a fiberglass ladder.
Originally Posted By: Thomas Ogryski This post was automatically imported from our archived forum.
I just can’t imagine anyone being foolish enough to change a service live. Any company allowing their electricians to do so, in almost all cases, is begging for a massive fine from OSHA. Any electrician doing so on his own is asking to meet his maker. Even unplugging the meter to de-energize the cable from the meter to the panel can be very hazardous when dealing with an old meter socket.
If you all want an eye opener, just do a Google on Arc Flash Injuries to see what the injuries look like and what the hazards are. Five people a day seek treatment at a hospital for this type of injury.
Most POCO's have rules that prohibit anyone that is not their employee from handling or accessing energized sevice conductors.
Originally Posted By: bbadger This post was automatically imported from our archived forum.
This is one of those questions without any correct answer.
Each power company has their own rules.
One power company may have the electrician cut the power off at the point of service another power company may 'flip out' if the electrician does that.
The best bet for an electrician is to schedule a shut down by the utility.
An electrician that cuts the live service conductors is actually violating OSHA rules even if they have the correct PPE.
That said many electricians, including myself have done this.
Quote:
OK, Jeff, so that begs the question: How do they work with live wires? (handling by the insulation and relying on that for protection?) I am really curious as I have never seen it done and I have a healthy respect for electricity.
PLEASE DO NOT USE THESE AS INSTRUCTIONS!
First we have to be clear if we are taking about an overhead or underground service.
With an underground service the power company must be involved as the electrician can not access the utility end of the service conductors.
With an overhead service I could use a fiberglass (or dry wood) ladder climb up to the service point and using insulated cutters and gloves cut one wire at a time in this order hot, hot, neutral/ground. That is easily done.
The reconnect is a tricker process as if for any reason the new service has a fault in it you will have a small explosion when the hot is reconnected.
For this reason it is wise to use a volt meter between the live power company hot and the dead hot of the new service. The meter should read 0 volts, any other reading indicates a problem that must be found.
AGAIN DO NOT TRY THIS YOURSELF!
I do not do this anymore since becoming more educated about how bad you can be hurt.
My fear is not a shock, my fear is a severe burn from arc flash and the resulting fall from the ladder.
By the way, the power company usually works from an insulated bucket truck and uses insulated gloves that allow them to touch live wires at 13,800 volts or more. The power company is also not covered by the same OSHA rules as electricians.
In my area the local power line guys will work live with 15,000 and below, other parts of the power company may work on live wires at much higher voltages, 250,000 volts etc.
At that point they do not exactly insulate themselves, they are more like a bird sitting on a wire, they are 'live' but not within reach of anything grounded.
-- Bob Badger
Electrical Construction & Maintenance
Moderator at ECN
Originally Posted By: NJwirenut This post was automatically imported from our archived forum.
I just did a service upgrade yesterday, and BBadger’s technique is pretty much how I do it, with the following changes:
Before cutting the service connections from the drop, I shut off the main and all branch breakers in the panel, and verify that the meter has stopped spinning. I also use a clamp-on ammeter around the service drop before cutting. You don't want to cut the wire under load...
I will never pull a meter from a socket live unless the socket is very recent and in good condition. I have had a few sockets fall apart when the meter is pulled, which would make for a bad day if the socket was live.
I use a megger to check the new service for shorts prior to energizing it.
I use insulation-piercing connectors for the reconnect. This way, I minimise the handling of live conductors. No stripping and taping like you would with a splitbolt. Just insert the 2 wires into the connector and tighten the insulated bolt with a socket wrench. Even with these, all work at the service head is done wearing lineman's gloves and a face shield.
Underground services get a disconnect from the utility, no exceptions.
Originally Posted By: pabernathy This post was automatically imported from our archived forum.
Quote:
Many (most) electrical contractors in my area change out service equipment (cables and/or boxes) without shutting down power from the utility.
Chicken I guess I am....been doing this over 17 years and going home to my family at night. It only takes 1/10th of a AMP to kill you if you are grounded right so why risk it.
IN VA you are required to contact the local UTY and have the meter pulled and the wires capped at the top of the mast....they leave it hooked to the required I-Bolt or what have you...but cut and capped....
We then run a new mast.....call the city for inspection, they come out...approve it ( you hope ) and then they contact the UTY to come and replace the meter and re-compression crimp the lines at the drip loops...........
I have NO desire to work on a service change or mast while it is still live...call me chicken...call me a cry baby.....just make sure you can CALL me.....rather than remember me.
Even the BEST electrician can get careless in the course of a day if it has been a LONG day......
Now we do work on some live wires....but in the case of a replacement of a service past or service latteral..........NO way fella.......not this electrician.
-- Paul W. Abernathy- NACHI Certified
Electrical Service Specialists
Licensed Master Electrician
Electrical Contractor
President of NACHI Central Virginia Chapter
NEC Instructor
Moderator @ Doityourself.com
Visit our website- www.electrical-ess.com
