How to train myself on "correct" HV wiring?
- Thread starter IVB
- Start date
IVB:
In order:
# 1, not too horrible IMHO. The worst is that picture is what the LV guy ty-rapped the coax to the HV. Really doesn't look too bad. Not artwork, but not horrible.
#2. Actually the splices shown...well let me re-word that, TAPS, for the BX is compliant and legal. The BX has the appropriate connector installed and the tap appears to be western union'ed to the K+T, friction taped, insulated and wrapped. The NM (Romex), if it had a similar connector, usually called a monkey fist, face or service entrance caplet, that would be legal also. Basically, you're supposed to have a fitting to terminate the new wiring method, but the open air connections are legal otherwise in the specific case of K+T. The installation of the fiberglass is what changes the install, nothing else besides the lack of a fitting.
#3, really not that horrible overall. My pet peeve is the method used to support the LV...that's not compliant.
For the sticklers out there, from the NEC:
300.15 Boxes, Conduit Bodies, or Fittings — Where Required.
A box shall be installed at each outlet and switch point for concealed knob-and-tube wiring.
Fittings and connectors shall be used only with the specific wiring methods for which they are designed and listed.
Where the wiring method is conduit, tubing, Type AC cable, Type MC cable, Type MI cable, nonmetallic-sheathed cable, or other cables, a box or conduit body shall be installed at each conductor splice point, outlet point, switch point, junction point, termination point, or pull point, unless otherwise permitted in 300.15(A) through (M).
(F) Fitting. A fitting identified for the use shall be permitted in lieu of a box or conduit body where conductors are not spliced or terminated within the fitting. The fitting shall be accessible after installation.
300.16 Raceway or Cable to Open or Concealed Wiring
(A) Box or Fitting A box or terminal fitting having a separately bushed hole for each conductor shall be used wherever a change is made from conduit, electrical metallic tubing, electrical nonmetallic tubing, nonmetallic-sheathed cable, Type AC cable, Type MC cable, or mineral-insulated, metal-sheathed cable and surface raceway wiring to open wiring or to concealed knob-and-tube wiring. A fitting used for this purpose shall contain no taps or splices and shall not be used at luminaire (fixture) outlets.
(B) Bushing A bushing shall be permitted in lieu of a box or terminal where the conductors emerge from a raceway and enter or terminate at equipment, such as open switchboards, unenclosed control equipment, or similar equipment. The bushing shall be of the insulating type for other than lead-sheathed conductors.
Followed by:
394.56 Splices and Taps
Splices shall be soldered unless approved splicing devices are used. In-line or strain splices shall not be used.
In order:
# 1, not too horrible IMHO. The worst is that picture is what the LV guy ty-rapped the coax to the HV. Really doesn't look too bad. Not artwork, but not horrible.
#2. Actually the splices shown...well let me re-word that, TAPS, for the BX is compliant and legal. The BX has the appropriate connector installed and the tap appears to be western union'ed to the K+T, friction taped, insulated and wrapped. The NM (Romex), if it had a similar connector, usually called a monkey fist, face or service entrance caplet, that would be legal also. Basically, you're supposed to have a fitting to terminate the new wiring method, but the open air connections are legal otherwise in the specific case of K+T. The installation of the fiberglass is what changes the install, nothing else besides the lack of a fitting.
#3, really not that horrible overall. My pet peeve is the method used to support the LV...that's not compliant.
For the sticklers out there, from the NEC:
300.15 Boxes, Conduit Bodies, or Fittings — Where Required.
A box shall be installed at each outlet and switch point for concealed knob-and-tube wiring.
Fittings and connectors shall be used only with the specific wiring methods for which they are designed and listed.
Where the wiring method is conduit, tubing, Type AC cable, Type MC cable, Type MI cable, nonmetallic-sheathed cable, or other cables, a box or conduit body shall be installed at each conductor splice point, outlet point, switch point, junction point, termination point, or pull point, unless otherwise permitted in 300.15(A) through (M).
(F) Fitting. A fitting identified for the use shall be permitted in lieu of a box or conduit body where conductors are not spliced or terminated within the fitting. The fitting shall be accessible after installation.
300.16 Raceway or Cable to Open or Concealed Wiring
(A) Box or Fitting A box or terminal fitting having a separately bushed hole for each conductor shall be used wherever a change is made from conduit, electrical metallic tubing, electrical nonmetallic tubing, nonmetallic-sheathed cable, Type AC cable, Type MC cable, or mineral-insulated, metal-sheathed cable and surface raceway wiring to open wiring or to concealed knob-and-tube wiring. A fitting used for this purpose shall contain no taps or splices and shall not be used at luminaire (fixture) outlets.
(B) Bushing A bushing shall be permitted in lieu of a box or terminal where the conductors emerge from a raceway and enter or terminate at equipment, such as open switchboards, unenclosed control equipment, or similar equipment. The bushing shall be of the insulating type for other than lead-sheathed conductors.
Followed by:
394.56 Splices and Taps
Splices shall be soldered unless approved splicing devices are used. In-line or strain splices shall not be used.
No listing needed for wire nuts in open air...it's an approved splicing method for 2 or more conductors. See NEC 110.14. Hell, for that matter, you could solder the connections and insulate with rubber tape followed by friction tape...still no box needed. We're talking taps here, not junctions. Look at picture # 3 closely...that romex is mid span in a run. We're also not talking underground or wet locations.
They also make connectors that allow romex to be spliced and plugged together that are 100% legal and don't require a box, only accessibility. Very commonly used in the modular home industry, but also in others as well.
They also make connectors that allow romex to be spliced and plugged together that are 100% legal and don't require a box, only accessibility. Very commonly used in the modular home industry, but also in others as well.
Neurorad
Senior Member
For low-voltage
Cable J-Hook
D-Rings
I've been using 2" PVC conduit clamps and metal conduit straps
The holes are large with the PVC fastening straps. You can use washers, but I use something labelled 'lathe screw' which have oversized heads (found with the structural fasteners at HD/Lowes).
I've even seen some people even use garage hooks for LV cable, that you'd use to hang a bicycle.
Cable J-Hook
D-Rings
I've been using 2" PVC conduit clamps and metal conduit straps
The holes are large with the PVC fastening straps. You can use washers, but I use something labelled 'lathe screw' which have oversized heads (found with the structural fasteners at HD/Lowes).
I've even seen some people even use garage hooks for LV cable, that you'd use to hang a bicycle.
drvnbysound
Senior Member
I've done a fair amount of HV work before and am comfortable doing the work. I've matched everything to existing work that has been recently installed w/o issue. That said, I do have a question... so I want to thread jack for just a second
I've recently had a workshop built. The contractor installed a sub-panel in the workshop which was pulled from the main panel of my home. To save myself cost, I explained that I would run all the electrical inside the shop. The question I have though... is there a limit to the number of receptacles that can be installed on a single circuit? I'm assuming yes, but wondering what the number is or some way of calculating what that number would be.
Let me know if additional information is needed.
I've recently had a workshop built. The contractor installed a sub-panel in the workshop which was pulled from the main panel of my home. To save myself cost, I explained that I would run all the electrical inside the shop. The question I have though... is there a limit to the number of receptacles that can be installed on a single circuit? I'm assuming yes, but wondering what the number is or some way of calculating what that number would be.
Let me know if additional information is needed.
neillt
Active Member
Believe it or not, there is no set maximum number of outlets per branch circuit according to the NEC.
But, if you know what your loads will be, the general rule of thumb is don't go over 80% of the rating of the circuit. This is part of the commercial electric code, but it is good advice for residential as well.
Edit: something to remember is that all garage and workshop outlets must now be GFCI protected.
But, if you know what your loads will be, the general rule of thumb is don't go over 80% of the rating of the circuit. This is part of the commercial electric code, but it is good advice for residential as well.
Edit: something to remember is that all garage and workshop outlets must now be GFCI protected.
drvnbysound
Senior Member
Thanks for the info. I was definitely planning to have the circuit GFCI protected. I can only operate so many tools at a time, so I'll probably never max out the circuit for the receptacles at any given time. I'll have a separate circuit for lighting, and another for A/C... and the subpanel has plenty of space for more if needed. My concern was really the outlets... due to physical location of the sub-panel and the receptacles I may end up with 2 circuits... I was just concerned with possibly putting more than allowed on a single circuit, so it's good to know there is no max.
drvnbysound
Senior Member
Neurorad said:
I do have a dust collector, table saw, and air compressor... all of which are 110VAC. But, yes... there are 220VAC models available.
wuench
Senior Member
I absolutely do not agree about leaving the open air wire nuts. Forget the meandering of what code allows put those in a jbox if you can. The whole point of a jbox is that if a wire comes loose any arcing or overheating is contained. Typical breakers do not blow from arcing, they blow from overload, so they will not prevent the issue. If you can't do the jboxes, then at least make sure they are tight and wrap the base of the nuts with electrical tape to help prevent them from coming loose, and clear everything flammable away from them, a kludge but better than nothing.
There is code and there is the spirit of the code. If you map common sense on top of code you begin to understand the reason for the stuff in there. Just play 3 year old and ask why. Why does the code say that, how does this prevent electrocution or a fire. Think about the next guy working on or near this stuff (most likely you) but assume he may not know where things are, or how they are connected. The reason for the box and conduit fill stuff is wires heat up (have you ever touched the cord to a space heater or toaster oven?). The reason for securing things every x inches or in boxes with clamps and staples near the box is loose connections create excess heat due to arcing. You can exceed code and no one will complain. Just watch some Holmes on Homes.
As far as pulling wire to boxes, I generally remove the boxes then you can reach around in the hole to pull the wire and put in a nice deep adjustable retrofit box when done. If you are careful it is not that difficult to do without damaging the wall.
And please, please use insulated staples.
And my favorite tool is my Linemans pliers
There is code and there is the spirit of the code. If you map common sense on top of code you begin to understand the reason for the stuff in there. Just play 3 year old and ask why. Why does the code say that, how does this prevent electrocution or a fire. Think about the next guy working on or near this stuff (most likely you) but assume he may not know where things are, or how they are connected. The reason for the box and conduit fill stuff is wires heat up (have you ever touched the cord to a space heater or toaster oven?). The reason for securing things every x inches or in boxes with clamps and staples near the box is loose connections create excess heat due to arcing. You can exceed code and no one will complain. Just watch some Holmes on Homes.
As far as pulling wire to boxes, I generally remove the boxes then you can reach around in the hole to pull the wire and put in a nice deep adjustable retrofit box when done. If you are careful it is not that difficult to do without damaging the wall.
And please, please use insulated staples.
And my favorite tool is my Linemans pliers
pete_c
Guru
drvnbysound,
In the 1980's I built a detached garage at my old home. At the time I had a master electrician; old neighbor help me some.
I ran water, gas, sewer, HV and LV in multple chases that I built from the house to the garage.
I did extend the house alarm panel to the garage. Into antique's a bit I used an old firehouse alarm bell ouside of the garage. I think I still have it. It is truely an antique and very loud relative to it being mostly mechanical.
Aside from main power I ran switched power from the house. It was a 24X 24 garage. I did actually divide up the outlets and lighting and other stuff in the garage. Everything literally was on separate circuits. I even installed analog cameras inside and outside of the garage at one time in the 1990's.
I do recall the neighbor / master electrician during the endeavor asking why so many circuits etc.
Aside from playing with my automobiles; I did play with other "stuff" in the garage which were mostly high amp draw things.
That said having multiple high amperage circuits helped me a bit. I did also have a natural gas shop heater hung near the ceiling at the time and some 8 double strips of flourescent lighting end to end for a daylight like workshop.
In the 1980's I built a detached garage at my old home. At the time I had a master electrician; old neighbor help me some.
I ran water, gas, sewer, HV and LV in multple chases that I built from the house to the garage.
I did extend the house alarm panel to the garage. Into antique's a bit I used an old firehouse alarm bell ouside of the garage. I think I still have it. It is truely an antique and very loud relative to it being mostly mechanical.
Aside from main power I ran switched power from the house. It was a 24X 24 garage. I did actually divide up the outlets and lighting and other stuff in the garage. Everything literally was on separate circuits. I even installed analog cameras inside and outside of the garage at one time in the 1990's.
I do recall the neighbor / master electrician during the endeavor asking why so many circuits etc.
Aside from playing with my automobiles; I did play with other "stuff" in the garage which were mostly high amp draw things.
That said having multiple high amperage circuits helped me a bit. I did also have a natural gas shop heater hung near the ceiling at the time and some 8 double strips of flourescent lighting end to end for a daylight like workshop.
BraveSirRobbin
Moderator
Don't forget to add low voltage wiring and outlets outside the shop, perhaps some up high for cameras, maybe even outlets in the ceiling.
