Question on adding branch to a panel - how do you guys access the knockouts?

Discussion in 'Electrical Forum discussion & Blog' started by Probedude, Apr 21, 2011.

  1. Probedude

    Probedude New Member

    Messages:
    137
    Location:
    CA
    I have a house built in 1965 with 100A service.
    Looking to pull 2 separate branches off the panel, 1 to each bathroom for a in-ceiling vent/heater. Per the manufacturer information on the panel door, adding a twin breaker into one of the available slots is allowed.

    Question though - how do you guys get to the panel knockouts to bring in another romex line? Exterior of house is stucco, interior drywall. Peak of roof comes down over where the service panel is so attic access is impossible to drill from there.

    Assuming that I need to open the drywall, it looks like the meter has to be pulled to be able to install a strain relief and then romex through the top of the panel. Coming in from the bottom would alleviate needing to call the Edison to pull the meter, but is this allowed?

    So how do you pro's add a branch circuit to a panel in a finished house?
  2. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    First thing I do is pull the meter. I have been doing this for more years than some here are old and have learned that one NEVER works in a live panel.
  3. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,797
    Location:
    Cave Creek, Arizona
    quote; First thing I do is pull the meter. I have been doing this for more years than some here are old and have learned that one NEVER works in a live panel.

    Here, that would be a good way to get a hefty fine. Once YOU break the meter seal, the utility does NOT know WHEN you did it, and whether you do it to install jumpers between meter reading times. ONE does work in a live panel when necessary, but then that is why they make "hot gloves".
  4. SacCity

    SacCity In the Trades

    Messages:
    189
    Location:
    Sacramento, CA
    You are adding circuits. Easy peasy,, done all the time no need to pull the panel...
    Most likly will need to cut two access panels, one near the panel it self and a second below the top plate of the wall

    On the projects that I've done I have always run one or two empty 3/4" conduits up for future service.

    But then I work on rentals were I have to go back to the same property year after year.
    Spend alot of time laughing at the work I did 30 years ago....
    Michael
  5. drick

    drick In the Trades

    Messages:
    392
    >So how do you pro's add a branch circuit to a panel in a finished house?

    I don't know if this is an inside panel or outside so I'm not entirely sure what your situation is, but this is how we do it:

    You can use any knockout -bottom, top, side, whatever. Try and pick one you can position a drill directly over as it makes the next step easier. To get the knockout out from the inside drill a small hole in the center of it, then stick a screwdriver through it and pry it out. If this is an inside panel usually the overlap of the cover is enough so you can cut a small hole in the sheet rock big enough for a connector to pass through, yet still be covered when you put the cover back on. If thats the case cut your hole, fish the wire up from the basement through the hole, strip it, put the connector on, then fish it back into the hole and up through the panel knockout. You can then slide the bushing over the wires and secure the connector. If this is an outside panel I'd have to see a picture to be able to advise you.

    -rick
  6. Probedude

    Probedude New Member

    Messages:
    137
    Location:
    CA
    Thanks everyone.
    This is an outside panel. The room on the other side of the panel in the house is a bedroom.

    Regarding pulling the meter, if I come in from below I don't need to pull it. From the top I would be calling Edison to pull it as I would not be able to tighten the lock ring on the romex clamp let alone get my hand up there to start it. It appears I wouldn't be able to fish the romex down to the breaker area either very easily with the meter in place - not to mention it would be live.

    From the bottom, no meter problems and I'll of course turn off the main breakers. Don't know if the panel is fitted wall to wall between two studs or not. Might have to go sideways through a stud with the feeds and then up into the header and then ceiling.

    The builder did put in 2 qty 3/4" conduit lengths for future expansion but they are already filled by previous updates to the house - electric oven in one, and 2 qty 20A feeds to a enclosed patio room in the other.

    I guess I'll go at it from the inside of the house. I can do drywall, not great at it, but better than I can do stucco.
  7. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    I have been doing this for over 44 years. I hold the highest license that the state of North Carolina issues as well as holding the highest certificate in electrical inspection.

    I have done electrical work of all aspects from wiring mobile homes to high rises, industrial and commercial.
    I would never install any circuit into any live panel. First it is against every safety law ever written, second it is very dangerous. Unless you have a calorie rated suit of at least 20, hat with shield, voltage rated gloves, and voltage rated tools then don’t open the panel and start poking around.

    Call the power company if you are afraid to pull the meter yourself but never install anything in a live panel.
  8. cacher_chick

    cacher_chick Test, Don't Guess!

    Messages:
    3,249
    Location:
    Land of Cheese
    If all electricans worked like that JW, they might be safer but they would also have to double their prices.

    The only time I have ever seen an electrician pull a meter was to change a panel and/or the feeders to the panel and then they call the power company when they are done. Here, the p.c. has to reinstall the meter and a new seal, and they won't do it unless the building inspector has left his approved inspection sticker.

    I suspect that thousands of breakers are replaced or branch circuits added every day, without anyone pulling a meter.
  9. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    There are also thousands out there that was working in live panels that are either maimed for life or dead.

    Now one might not much care about their self but the families are the ones who are sufferings the most. If you don’t care about yourself at least think about the ones that will have to tend and support you should something go wrong.

    Don’t just put yourself and your family in jeopardy in the name of saving a dollar as it may and very possibly could end up costing more in the end.
  10. DonL

    DonL Jack of all trades Master of one

    Messages:
    4,301
    Location:
    Houston, TX

    Hello JW and the Group.

    I hope all is having a good day.

    JW first of all You are to smart for your britches.

    I have worked on many 600 Volt 3 phase Systems, With power ON.
    If I would have to kill power then, It cost money some where in the plant.
    That is why we are experienced, working with electricity, and need to be licensed.

    I do agree that it is safer to work with the power off, but no can do, Many times, In the real world.

    A home owner may not be able to do the work, without a permit and inspection after the work is done.
    but when I need to pull a meter I just tell them why I pulled it, Normally only to change the main input breaker,
    they say fine and put a new seal. I am in Texas, may very state to state, and who you know.

    I am sorry that everyone is not as smart as You.
    But sometimes we have to uses the tools that we average no Nothings have. You know it all, Wish I did.

    Maybe in my next life.

    Turning Off the power when you read voltage is safer, but it gives you a bad reading...

    Have a great Day.

    DonL.
  11. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    Don you make a very good point here;
    What we must remember is those asking questions here are do-it-yourselfers and not ripe old experienced licensed electricians. When we answer them we need to keep their safety at the front of our minds as well as their inexperience.
    And I hope that you had on your Personal Protective Equipment while doing so. Ever pay any attention to that poster somewhere in the shop where you work, you know the one from OSHA? Ever pay any attention to the first line, “It’s the Law�

    I do hope that you would consider the type people that post and read this forum. Know that most have little or no experience. Do you really think it is a good idea for them to start poking copper into a live panel?

    I to have worked on live circuits and panels and as high as 4160 volts but when I did I was dressed for the task at hand. Checking voltages in a residential panel requires hard hat, eye protection, voltage rated gloves, fire retardant clothing, and the proper rated meter.
    Now I don’t know how smart I am but I am smart enough to know that should something go wrong and I wasn’t doing things in a safe manner it won’t be only me that suffers but my family will suffer also. I love my wife and children to much to put them through something that I could have prevented.

    Knowing that most home owners don’t have the PPE required to work in a live panel or even know about the ratings of meters I for one am not going to start telling them it is alright to just poke around with enough heat energy to burn them to a crisp.
    I would hope that me stating the dangers of electricity would not be Offensive to you in any way. I would hope that as a seasoned veteran you would take their wellbeing into consideration also.
  12. dlarrivee

    dlarrivee New Member

    Messages:
    1,172
    Location:
    Canada
    I'm confused, if I shut off the main breaker is the panel still considered live?

    I've never seen any electrician pull a meter, nor is it acceptable in my area...
  13. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,126
    Location:
    New England
    See those big wires coming into the panel? Those are hot unless you pull the meter (or have some other shutoff before the panel which is unusual but not a bad idea). The bus bars are not energized, but there is plenty of power in the panel until you remove the meter!
  14. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    I have reached a peak in my electrical career at which I am very fortunate. Twice a year I get to sit with some of the greatest minds in North America including some from Canada. There is a big push with the US and Canada to bring the NEC in more uniformity with the two nations as well as all of the NFPA documents. With both nations safety is the forerunner.

    Across both nations there are several electricians that do not follow all the rules set forth for their safety as well as the safety of others. Then we have the do-it-yourselfer that has no professional training at all and only has the experience of watching someone else do something.
    Then the attitude, “I can do that. It’s not rocket science.â€

    Most statistics concerning electrical accidents will be workplace related as the government mandates that these accidents be recorded but homeowner accidents are not recorded.
    In one of the safety training programs that I teach I have several pictures of homeowners who have lost hands, arms, legs, and two who lost their life doing weekend projects around the house. One of the fatalities was a homeowner that wanted to exchange a light for a fan. He had crawled in the attic to mount a fan rated box for the fan but did not de-energize the circuit. It was almost an hour before the rescue could get to him.

    It only takes one tenth of an amp to kill. In a 15 amp circuit there will be 150 one tenth amps. In a service panel simply multiply the size of the breaker by point one.
    The conductors supplying the main breaker are not fused and can deliver up to and beyond 10,000 amps of electrical energy. With the main turned off the terminals that these service conductors land on are still live.
    To fault one of these to ground or too short across both the only thing to stop the flow of current is the transformer supplying them.

    I can assure you that there is not a place on earth that it is not acceptable to remove the meter before working in a panel if the proper procedure is followed.
    It is only when someone wants to save a dollar and does not follow the proper procedure that removing the meter is not acceptable. It is only when someone wanting to save a dollar that the life changing accidents occur. There is a reason behind permits and inspections, it’s called proper procedure.

    What most homeowners never think about is the impact an accident will have on their family it will be the family that does the most suffering, loss of income as well as the medical expenses.

    The sad part is the safety issues never hit home until it is too late and then it is all that anyone thinks about.
  15. dlarrivee

    dlarrivee New Member

    Messages:
    1,172
    Location:
    Canada
    So you're a politician/inspector then?
  16. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    No I am a safety minded person with your wellbeing at the foremost of my mind.

    I am a person who has experienced flash overs and electrical explosions as well as one who has investigated such incidents. Yes I have been involved in electrical incidents caused by my own careless unsafe maneuvers.

    I am the person who knows that anyone who thinks there is no danger in doing electrical installations have taken the first step toward being permanently maimed or even killed.

    I am a person who has seen firsthand and experienced the loss to families who suffered from someone doing something in an unsafe manner.

    I am a person that was directly involved with a family where the husband lost his right arm at the shoulder and lost not only his home but his family simply because he wanted to change the circuit to his heat pump himself and shoved the cable into the main breaker of his service panel causing a flashover in which he received second and third degree burns to his arm, face and chest. He didn’t even turn the main breaker off. To visit with him today, if you can catch him sober and he will tell you that he had done this type of installation hundreds of times without any problems. It only took once to stop him from doing anymore electrical installations of any kind.

    I am a person who thinks about your family and the pain and suffering that would be imposed on them should you do something that could cause you to be injured for life or even killed.

    I am a person who everyone wants to belittle because of my preaching safety and the old adage that one ounce of prevention is worth a ton of cure.

    I am not against someone doing their own electrical work as long as that work is being done in a safe and compliant manner. Just because someone is a homeowner wanting to do something their self in no way relieves the dangers that arise from electrical hazards. Safety first, safety last, safety always.

    click here
    Last edited: Apr 25, 2011
  17. DonL

    DonL Jack of all trades Master of one

    Messages:
    4,301
    Location:
    Houston, TX
    Hello JW and the Group.

    Thank You for the reply JW.

    I realize that people asking questions here are do-it-yourselfers.
    If they were experienced licensed electricians, They would not need help.

    And I do not want anyone to get hurt, Physically, Mentally or Verbally.

    But I think that smart people come here to get help, Not a Lecture on why
    they are wasting there time and why they should not do something, Your way.

    There are other knowledgeable people on this forum that have offered help and
    have been there and done that, with ease, and it works. Just not Your way.


    I looked at Your link (http://esfi.org/index.cfm/cdid/11015/pid/10262) and it said;

    * Make an effort to learn about your home electrical system so that you are able to safely navigate and maintain it.
    * Never attempt a project that is beyond your skill level. Knowing when to call a professional may help prevent electrical fires,
    injuries, and Fatalities.
    * Always turn off the power to the circuit that you plan to work on by switching off the circuit breaker in the main service panel.
    * Test the wires with a voltage meter before you touch them to make sure that the power has been turned off.
    * Be sure to unplug any lamp or appliance before working on it.
    * Use a GFCI with every power tool to protect against electrical shock hazards.
    * Never stand in a puddle or on a damp floor when working directly on or near electricity.
    * Always have your work inspected upon completion to ensure that it has been done correctly.

    This is all good information, But I see nowhere there that says to pull the meter.
    Pulling the meter is considered tampering, because You only own the equipment after the meter.
    But the meter can be pulled in an emergency as the Fire Department will normally do.


    You say;
    "I am a person who everyone wants to belittle because of my preaching safety"

    I think that if others belittle you it is that maybe sometimes you deserve it.
    Preaching is something better left to preachers in a church, for people who want to go
    and hear it, Not on the Forums, Unless someone asks You.


    This Post was originally a simple question;
    "Question on adding branch to a panel - how do you guys access the knockouts?"

    I never seen you give an answer to the question, If You did then I missed it, Maybe
    You gave it in some electrical code.


    You also said;
    "I would never install any circuit into any live panel."

    With all of Your experience, Why not ?. It is done safely every day.


    I do believe that a person should have a working voltmeter and check to make sure
    that the circuit is dead before working on it. That is a given. Respect Electricity.


    You have a way of preaching and lecturing, and running good people off.
    They want a straight answer, not a section in a code book, that they may not understand,
    or even need to understand. In our real world thay dont need all that for what they are working on.


    You should leave some of your lectures in your class room, And leave the preaching
    up to the preachers in church. Or become a preacher yourself, in your church.


    You are not Offensive to me in any way, You just rub people the wrong way.


    I hope You understand. Sorry if my english doen not suit You. You should understand.

    I know that You are a good person, and have a good heart.


    That is just my thought, But I know a lot about nothing...


    Have a Great Day.


    DonL
  18. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    The very last line in that link, Always have your work inspected upon completion to ensure that it has been done correctly, will give whoever that bought the permit the right to pull the meter anywhere on this planet. That is the purpose of permits in the first place.

    The third line in that link, Always turn off the power to the circuit that you plan to work on by switching off the circuit breaker in the main service panel, means that if it is the main panel that is to receive the work then it is to be turned off and this is done by pulling the meter.

    Doing these two items will insure that the second line is adhered to; never attempt a project that is beyond your skill level. Knowing when to call a professional may help prevent electrical fires,
    injuries, and Fatalities.
    There is no such thing as a simple answer or simple job when dealing with electrical energy.

    It takes one calorie of energy to raise the temperature of one gram of water one degree Celsius. How many calories are there in 120 volts at 15 amps?
  19. DonL

    DonL Jack of all trades Master of one

    Messages:
    4,301
    Location:
    Houston, TX
    Good Morning JW and the group,

    JW, You left out variables needed for an accurate answer to your question.

    Depends on the duration, of the 120 volts at 15 amps.

    Assuming you are talking about the power of 1800 watts then;

    1800 watts = approximately 430 calories / second at 1 atmosphere.

    Have a Great day.

    DonL
  20. cacher_chick

    cacher_chick Test, Don't Guess!

    Messages:
    3,249
    Location:
    Land of Cheese
    I'm glad JW is not involved with the NTSB.
    People driving cars would be completely out of the question.

    You don't have to reply JW, I'm just pokin' fun at ya...... :eek:
Similar Threads: Question adding
Forum Title Date
Electrical Forum discussion & Blog Quick question on adding to 3 way light Sep 21, 2012
Electrical Forum discussion & Blog Question regarding wireless light switch Wednesday at 7:16 AM
Electrical Forum discussion & Blog Hard wired 220v GFCI Questions Jun 2, 2014
Electrical Forum discussion & Blog Air compress 240v question Jun 1, 2014
Electrical Forum discussion & Blog GFCI receptacle questions May 16, 2014

Share This Page