Wiring Fox paw

Fred

@EBEBRATT-Ed said: @Fred and that picture I do believe is the old rubber covered wire in that disconnect. Same as the K & T stuff only in conduit. And OMG they forgot to color or tape the neutral leaving the disconnect white HOLY VIOLATION. Also the equipment ground is the conduit not a wire. Typical of the way everything was wired back then and nothing wrong with it.
@EBEBRATT-Ed the covering on the wire is different than any T&B I've ever seen but it isn't the covering they use today so I'm not sure exactly what it is. You are right, they painted the neutral on the incoming side but not the one that leaves the disconnect. I'll have to take a cover off of one of the breaker boxes and see if it is painted there??? There is a solid ground wire (maybe aluminum) on the conduit and the twisted copper wire goes to a water pipe.

JUGHNE

Fred, so you have a house full of ITE Bulldog Pushmatics.
I had to buy some for replacement and the only thing new available was Chinese knock off, way over priced.

I do have some in stock if you need any, some even new.

What would eventually happen is the mechanical part of the reset feature would fail. They could be on and say "off" and visa versa. Worst yet was because the way the wires lay down I have seen the right side connected to one 240 VAC CB and the left connected to the CB below it. You shut off the breaker and the heater quits working because you disconnected one leg only. Then the real surprise you take the wires off of the CB that is off and one of them is hot from feeding back thru the heater from the other breaker. Learned to really check that eventually.
Also don't slip off the "bolt-in" screw if you are trying to install a new breaker. I have seen a panel with a 3/8" hole burned completely thru the back. Don't know what the guy's screwdriver looked like but it had to be a real sphincter testing moment.

Fred

@JUGHNE , Yes! Bulldog Pushmatics in all the boxes. I know about the 240VAC's I learned that the hard way a few years ago, LOL. I also learned at that time the ITE's were getting hard to get so I bought a few 15A, 20A, 30A and one or two 40A and 50A, just to have them on hand. I have only had to use one 15A in the 26 years I've been here but I have them if/when needed. If you open the pic at the bottom of my post (That didn't post like the other two pics for some reason) you will see the new boxes of breakers on top of the disconnect box. There are a few stored inside that disconnect box as well. I really don't like the way the double pole breakers are linked together!

EBEBRATT-Ed

For all normal wiring, receptacles, lighting, electric heat, stoves, dryers, dishwashers, disposals etc. The wire size is supposed to match the breaker size (although running larger wire if it can be terminated in the circuit breaker lugs correctly (without cutting strands) is fine), Wire size is sometimes increased due to ambient temperature (hot boiler room, power run on a roof etc.) or just because it was in the truck.

usually but not always:
#14 wire 15a bkr
#12 wire 20A
#10 wire 30A
#8 40 wire40A
You probably will find instances where this isn't held to. Depends on the calculations. but this is safe


Now, as @GW mentioned Motor Circuits, furnaces, condensers, roof top units, ductless splits, window units anything with a motor FORGET ALL OF THE ABOVE. On packaged equipment ...follow the name plate.

All equipment will state on the name plate MCA (minimum circuit amps) this not the actual amp draw but the amp draw with the start up allowance included. The calc is done for you.

so a pc of equipment with a MCA of 28 could be wired with #10 30 amp wire. The nameplate wil also tell you the max fuse or cb size MOCP (maximum overcurrent protection)

So you could have a pc of equipment marked with an MCA of 28 #10 wire and the MOCP could be 40A (circuit breaker)

So packaged equipment....just follow the name plate. Unless you have an exceedingly long run, or the wires are exposed outdoors (high ambient) the wire size and breaker size on the name plate will be fine, it's been tested and passed UL that way.

Now, straight motor circuits (not packaged equipment) lets say you have a 3 hp exhaust fan 208 volt 3 phase.

wire size= code amps you have to look the motor up in the code book, cant use nameplate amps.

but RULE OF THUMB for 208/230 3 phase it's about 3A/horsepower (cut in half for 480v3 phase) so in this example 3hp x 3A=9A X1.25 (start-up factor)=11.25 amps so you could use #14 wire (rated 15A).

To size the cb or fuse take code book amps x 1.75 for a Time delay fuse or cb so 9 x 1.75=15.75 so a 20 amp breaker

The overload heaters in a motor starter are sized using the motor name plate amps not code book amps.

These are the general rules which apply "most" of the time.

the code book is full of exemptions

GW

thanks for all of that, so it's a myth that the wire MUST be size to handle the bigger breaker? You CAN have a 40 amp breaker and a 10 gg wire? I can certainly understand the argument for upping the wire size to match the breaker, but it's it's not required, then it's not required.

Jamie Hall

Two other comments to the above -- the wire sizes apply to copper. If for some lamentable reason you are using aluminium, you must go a size larger, and all fittings -- breakers, switches, sockets, whatever, have to be rated to be used with it. Don't use it if you can help it. The other comment is that on long runs -- over say 100 feet -- which will be fully loaded, check that the voltage drop is within limits. The code books have tables for that. You may have to go up a size to allow for the voltage drop.

Fred

I would have thought that sizing the wiring to the breaker amperage would be mandatory, by code. It would seem to me that a circuit may be used for a piece of equipment today and five or ten years from now be used for something completely different and I would have assumed that if I had a pre-wired 40 Amp breaker/circuit available that the wiring would be matched to that breaker. seems like there is a lot of risk to do otherwise and also a lot of reworking if the wiring is matched to the connected equipment rather than the circuit breaker. I'll have to ask our Housing inspector what our code requires.

ChrisJ

@Fred Not only that, but you can run a #12 wire, and splice in a #14 down the line as long as the breaker is sized for the 14 wire.

This was something I was amazed by as well. Apparently, if anyone has any intention of changing a breaker they are expected to know everything that is on that line, and why.

The circuits I just ran to my attic are a mix, but I labeled the boxes on the insides of the cover for what I did, and why in case I forget. I have #14 romex from the panel to the EMT, then it's #12 THHN up to the attic and goes back to #14 romex in the attic. I did this to de-rate the wire in the EMT for temperature so I can add more if I want to down the road.

They are of course fused at 15A.

Fred

@ChrisJ I am amazed! In my house I'm sticking with matching the wire to the breaker. Besides, I never use 14 gauge for anything. I like to be able to switch out a 15 Amp breaker for a 20 Amp and not worry about it but that's just me.

JUGHNE

As far as MOCP: most ACU state HVAC CB or fuses. If it states only "fuses" then a fused circuit must be used, usually in the outdoor AC disconnect. I believe fuse only MOCP is rare today for ACU's.
However I just have to do a power supply for church bell ringers that states "30 amp fused disconnect", factory insists on fuses but they don't know what type
Fuse catalogs can be as involved as light bulb/lamp catalogs.
They will get at least FRN or more exotic if I have them.

Jamie Hall

Keep in mind that one can always -- and safely -- use a larger wire size than the fuse/breaker is rated for, provided only that you can secure it properly in the terminal lugs. And as I said above, for longer runs you may have to, to keep the voltage drop to where it needs to be (particularly for motor loads).

The thing about fuses, particularly in the larger cartridge sizes, is that they come, as @JUGHNE said, in a bewildering array of capabilities -- the amperage rating is by no means the only consideration. That depends on the equipment the fuse is protecting. I would have thought that the ACU he mentioned would say what type they wanted...

JUGHNE

Jamie, this is an electronic AC to DC power supply for electric bell hammers applied to a 1915 church bell tower.
(A lot of steps and ladders )

ChrisJ

Fred said:

@ChrisJ I am amazed! In my house I'm sticking with matching the wire to the breaker. Besides, I never use 14 gauge for anything. I like to be able to switch out a 15 Amp breaker for a 20 Amp and not worry about it but that's just me.

Fred,
If the circuit can support a 20A interrupter why would it have a 15 in the first place?

There are rules to this and there are good reasons for them. There's absolutely nothing wrong with #14 wire on a 15A fuse, other than I think it may be against code for receptacles now days.

I also feel there's nothing wrong with aluminum wire provided it's sized appropriately and the correct connectors are used. Keep in mind, most power lines are aluminum as is the service line to your house. Aluminum got a bad rep because the wrong connectors were used and it was mixed with copper.

Fred, if you don't like me mixing #12 and #14 wire on a 15A circuit due to derating in a conduit, you really won't like the multi-wire branch circuit I have. This is a 12-3 wire running two independent 120V circuits on one neutral.

Here's the required handle lock.



It's also labeled as such at the panel and the junction box. The handle is so the circuits can trip independently, but if you shut them off both handles are forced off for safety reasons. This was also to code when I installed it.

Jamie Hall

JUGHNE said:

Jamie, this is an electronic AC to DC power supply for electric bell hammers applied to a 1915 church bell tower.
(A lot of steps and ladders )

What fun! And I know what you mean by steps and ladders. I hope they are in better shape than the ones in my church...

ChrisJ

Jamie Hall said:

JUGHNE said:

Jamie, this is an electronic AC to DC power supply for electric bell hammers applied to a 1915 church bell tower.
(A lot of steps and ladders )

What fun! And I know what you mean by steps and ladders. I hope they are in better shape than the ones in my church...

You have your own church?

You know what they say about those who fart in church right?

Fred

@ChrisJ , I absolutely have no problem with 14 gauge wire on a 15 Amp breaker. I just don't see a reason to use 14 gauge. The cost difference is minimal and the flexibility of having 12 gauge just seems like a bonus to me. There are a couple circuits that I have for some equipment where the manufacturer says a 15 amp breaker must be used so I have a couple 15 amp breakers but 12 gauge wire. When I bought my son's house, all the breakers were 15 amp but all the wiring in the house was 12 gauge. I changed out all the breakers to 20 amp. That was 10 years ago. 14 gauge wire was not popular or used much (around here anyway) until maybe 40 or so years ago. 12 gauge was the standard, then as lower cost tract homes took off, lower cost building materials took off as well and back then there was a reasonable pricing difference.

EBEBRATT-Ed

Just remember that

overfusing a circuit is for motor circuits only and with good reason. The larger breaker or fuse (in comparison to the wire) is for short circuit protection( believe me a #10 wire shorted will trip a 60 am breaker real quick) and to handle the starting load without nucince trips.

And also remember all motor circuits have some sort of thermal protection built into the motor circuit weather its a motor starter with overloads, a VFD or thermal protection in the motor. This prevents the circuit from being overloaded, the thermal trips to prevent overload the breaker protects against shorts. That why they allow overfusing

A lot of electricians like to run #12 cause you can get more receptacles on a circuit. Me I prefer #14 and use it for all lighting and receptacles circuits except where #12 is required now for:
Laundry circ
Kitchen & dining (small appliance circ)
bathrooms
and probably other places I forgot

I usually hit the garage or workshop area with at least 1 #12 circ for power tools although not code required.

NOTHING wrong with aluminum wire. If you got power to your house I'll bet a weeks pay that most of you have aluminum service entrance cable feeding your house...go check underground or overhead everyone uses aluminum........of course they do electricians are cheap

The problem with aluminum wired houses 1965-1975 mostly was that the receptacles and switches available at that time had never been tested with aluminum wire. The wire wasn't the problem, the terminations were. Most receptacles now are are marked CU for copper or AL for aluminum or cu/al for both

As far as mixing wire sizes the code states that "the amperage of the circuit is determined by the size of the overcurrent protection" so you can always use bigger wire (although some get confused)

@ChrisJ multiwire circuits are common although the code "sort of" frowns on them I guess is the way to put it. Some have gotten confused. Its important to remember that the two hots in a multi wire red & black have to come off opposite legs (240) volts between them of the panel. This is to prevent the neutral from being overloaded as it only carries the imbalance.

also, multi wire circuits must come off a two pole breaker (although I think? a handle ty on two single pole breakers can be used) not sure

This however hasn't always been true so when you run across a multiwire be careful if one side is hot the neutral is also carrying current. At one time you could use two singles or two fuses and then they could be attached to the same leg (inadvertently) which would be WRONG

JUGHNE

AFCI and GFCI combo CB's have pretty well taken multi wire branch circuits out of the residential system.
I used to use a lot of multi wire for home runs, (run one cable instead of 2), if that panel gets changed and relocated more than 6' of cable length from the original location, then those circuits need AFCI/GFCI CB's. That won't work on multi wire HR circuits. I have put 60 YO cables on AFCI/GFCI combo CB's and crossed my fingers.....so far no call backs.

ChrisJ

JUGHNE said:

AFCI and GFCI combo CB's have pretty well taken multi wire branch circuits out of the residential system.
I used to use a lot of multi wire for home runs, (run one cable instead of 2), if that panel gets changed and relocated more than 6' of cable length from the original location, then those circuits need AFCI/GFCI CB's. That won't work on multi wire HR circuits. I have put 60 YO cables on AFCI/GFCI combo CB's and crossed my fingers.....so far no call backs.

My main beef with that is what, $33 per QO breaker vs $7?
I understand their use but even I won't pay that for them unless forced to. That adds up especially in a 40 POS panel with most positions used. $231 vs $990 for 30 positions.

KC_Jones

@Fred while I understand your concept of using 12 ga everywhere I can tell you from personal experience that 12 ga wire on a lighting circuit can be a huge PITA. Most especially if you are daisy chaining some of the newer pot lights. Those boxes don't give much room and in some cases are not rated to handle enough 12ga wires so stuffing them in would be a code violation. To each their own, but I would never ever use 12ga on residential lighting.

Jamie Hall

Couple of thoughts. As usual... first, to clear up a confusion -- I have no problem with aluminium wire -- provided that the proper connectors are used. As has been noted several times, the odds are very high indeed that the service entrance wires are aluminium, as will wires between buildings in, for example, agricultural work.

Second -- @EBEBRATT-Ed mentions motor circuits and some of their peculiarities. This is one area where fuses have some real advantages, as the fuse type can be selected to match the characteristics of the motor (and starter, if present) used, and really do a good job of protecting the circuit and the motor and starter (if any!). This is particularly true for motors which do not have reduced inrush type starters.

Fred

KC_Jones said:

@Fred while I understand your concept of using 12 ga everywhere I can tell you from personal experience that 12 ga wire on a lighting circuit can be a huge PITA. Most especially if you are daisy chaining some of the newer pot lights. Those boxes don't give much room and in some cases are not rated to handle enough 12ga wires so stuffing them in would be a code violation. To each their own, but I would never ever use 12ga on residential lighting.

@KC_Jones , I only have four pot lights in my house and they make many styles. I haven't had any problem with 12 gauge wiring for lighting, probably because my joists/rafters are 12" so I can use deeper boxes, if needed. If it were a problem, I wouldn't have a problem going from a wall switch to the light fixture(s) with 14 gauge but I haven't had too so far.

JUGHNE

Chris, $33.00 is what the first GFCI CB's cost in 1969 dollars.
The outlets were not much cheaper. Both created a lot of nuisance callbacks. The first AFCI devices were troublesome also, but seem to have the bugs worked out now.

And people are being forced to pay for these today....

EBEBRATT-Ed

Yes, The manufacturers have lobbied and bullied the code making panels into using arc fault breakers weather we need them or not. I have my own opinions on that.

Even though I keep my electrical license(s) and do all the code updates I don't wire houses any more....well almost never so I don't bother keeping up to date on the "house stuff" unless I have too.

If I do any wiring it's commercial stuff AC, boilers, motors HVAC stuff so I try and stay up to date on that stuff....but that stuff seldom if ever changes. Most all the changes are in house stuff

Basically now a new house the whole thing has to be arc fault.....or it's getting real close to that

GW

well-- i love me some gfi on the condensate pumps

JUGHNE

There was the same battle with the GFCI devices in the late 1960's. Code wanted them and house builders were screaming.
However, I know of a mother who dropped the hair dryer into the tub and lost 2 of her 3 baby children immediately. (40 miles away)
Would the GFCI saved them? Not sure.....but you would not wanted to be the electrician who left them out if code required it at the time.

The AFCI are required in any thing new. What really needs them if the old house with only 2 worn outlets per room. You end up with extension cords run around that turns to crap shortly.

Went to a house fire where the tenant run an extension cord over the window to run the fan. Either the cord or fan shorted out and started the curtains on fire. Might have eventually tripped a CB. Little damage, the dog woke every one up.
Now the landlord wants to sue the tenant because his cord or fan started the fire. There were 2 outlets in the bedroom.

ratio

I installed a few combo AFCI/GFCI breakers a few months past. I picked up one of these to test them. Of the the breakers, the tester tripped one fine. One made a funny noise, failed the test, but tripped anyway. I condemned it & brought in another one. That one didn't trip at all. I called tech support, they said that the tester only simulates an arc fault & it's not guaranteed to operate the breaker. Huh. That suggests to me that the test button only tests the trip mechanics, not a functional test.

The laws requiring the use of AFCI breakers aren't intended to make us safer, they are intended to make AFCI breakers sell. That has a side effect of making them cheaper, or better, or better & cheaper. Safety is merely a side effect of the laws.

For the record, I've seen first-hand the kind of fault that an AFCI breaker is supposed to catch.

EBEBRATT-Ed

I don't have a problem with AFCI if they improve safety.

My problem just as @JUGHNE mentioned about GFCI in the late 60 the AFCIs came to market as a sales ploy. A lot of them didn't work properly yet we are forced to install them.

Maybe the problems have been fixed by now but they came to the market without in some cases being properly tested

ratio

They wouldn't have been tested if they hadn't been forced into the market. Safety by secondary causes is a lousy plan.

ChrisJ

The next thing I want to know is what is the power consumption of a AFCI breaker?

I was surprised to find out what some GFCIs consume.

The cheap 2 prong plug GFCI on my monitor top consumes about 2 watts all by it self. Most quality GFCI receptacles are lower than this, but not all and not by a lot.

Solid_Fuel_Man

The AFCI is a sticky mess. Check out the many YouTube videos on people "testing" them. A series arc is the real killer and none of them will trip in a series arc. The claim that the dry waller will hit some Romex with a screw is a possibility, but if everything was the 1.25" depth or nail-plated them someone did something wrong.

Getting back to the K&T discussion, it is generally considered unsafe where it comes into boxes etc. I would not have it in my own home, although the home I grew up in had lots of it still in use, still does too. The 4- main&range, panels always ended up with 3 or 4 circuits on each of those 4 fuses which always ends up being severely over fused. Simply separating all of out on 15A circuits usually solves that problem.

I have a problem with #14 wire in buildings as it has been proven that a 10,000aic hit for the minimum of 3cycles will damage the wire. So that said, only a fuse can clear a fault in less than 3 cycles, so fused #14 wire is OK, but breakers are not capable of properly protecting a #14 circuit. I do love working with #14 though...so easy.

It is my opinion the BX (jacket as grouping conductor) is the most dangerous wireing method out there, add in an FPE panel and you have the perfect storm waiting to happen.

If there is a ground fault, and the steel jacket is asked to carry the fault back to the panel the resistance of that steel will make a nice heating element in the walls of tinder. We've tried it on a piece of old BX, and 60' of it wouldn't trip a 20A breaker. You either need an equipment grounding conductor or not, a wound steel jacket is somewhere in between.... bad stuff.

Taylor

ChrisJ

Solid_Fuel_Man said:

The AFCI is a sticky mess. Check out the many YouTube videos on people "testing" them. A series arc is the real killer and none of them will trip in a series arc. The claim that the dry waller will hit some Romex with a screw is a possibility, but if everything was the 1.25" depth or nail-plated them someone did something wrong.



Getting back to the K&T discussion, it is generally considered unsafe where it comes into boxes etc. I would not have it in my own home, although the home I grew up in had lots of it still in use, still does too. The 4- main&range, panels always ended up with 3 or 4 circuits on each of those 4 fuses which always ends up being severely over fused. Simply separating all of out on 15A circuits usually solves that problem.



I have a problem with #14 wire in buildings as it has been proven that a 10,000aic hit for the minimum of 3cycles will damage the wire. So that said, only a fuse can clear a fault in less than 3 cycles, so fused #14 wire is OK, but breakers are not capable of properly protecting a #14 circuit. I do love working with #14 though...so easy.



It is my opinion the BX (jacket as grouping conductor) is the most dangerous wireing method out there, add in an FPE panel and you have the perfect storm waiting to happen.



If there is a ground fault, and the steel jacket is asked to carry the fault back to the panel the resistance of that steel will make a nice heating element in the walls of tinder. We've tried it on a piece of old BX, and 60' of it wouldn't trip a 20A breaker. You either need an equipment grounding conductor or not, a wound steel jacket is somewhere in between.... bad stuff.



Taylor

Square D QO breakers have a magnetic trip in 1 cycle at 60Hz. Actually, it looks a bit under 1 cycle to me. They also say their electronic breakers are even faster, but I didn't read much into it.






Here's an interesting read on circuit protection from Cooper/Bussmann.

http://www.cooperindustries.com/content/dam/public/bussmann/Electrical/Resources/solution-center/technical_library/BUS_Ele_Tech_Lib_Conductor_Protection_Wire_Cable_Protection_2.pdf


http://static.schneider-electric.us/docs/Circuit Protection/Molded Case Circuit Breakers/0100-400 A Frame FA-LA/FA-FC-FH/0600DB0105.pdf

EBEBRATT-Ed

There is no doubt in my mind that fuses are far superior to circuit breakers. Especially when high interrupting is needed fuses can do that for far less $$$

Circuit breakers are a problem and it's not just FPE

If you read the fine print about circuit breakers they are supposed to be "exercised", tested" etc. etc.

JUGHNE

Ed, I agree with that. However for the average homeowner I believe CB's to be safer. Few HO will open a panel and install a larger CB. But given the chance to over fuse a circuit it will be done. I have seen Fustat adaptors pried out with pliers and screwdrivers so that time delay 30 amp or even that penny installed. Copper tubing will fit nicely in cartridge fuse holders also. FWIW

ChrisJ

I'd love a panel with both breakers and fuses.

For example, something like a 15A breaker with a 20A fuse in line with it for each circuit.

ratio

Be careful what you wish for. Our right-pondian brothers already have Christmas Light plug on everything—you know, the ones with fuses in 'em. 'Course, they use some crazy voltages too.

Oh, and how 'bout these fuses:

JUGHNE

I see several code violations there....it looks like that bottom fitting should have an NM bushing on it.....was the proper torque wrench used on the lugs??.....and also the tubing is not reamed, this impedes the air flow to cool the tubing.

ChrisJ

ratio said:

Be careful what you wish for. Our right-pondian brothers already have Christmas Light plug on everything—you know, the ones with fuses in 'em. 'Course, they use some crazy voltages too.

Oh, and how 'bout these fuses:

You mean the UK?
I don't consider 220V to be "crazy voltage".

I also don't mind fused plugs. Everything I've designed is fused.

ratio

All those other ways are Different and Not The Way We Do Things Here, and are therefor suspect. ( <- a funny )

I like our way better, but it's possible I have a slight bias. Maybe.

Jamie Hall

There is a way to defeat almost any protective device known to man. There are also ways in which accidents can happen which will defeat any known protective device.

And then there are idiots who set about doing so.

A fuse can be defeated, and people will do it. Circuit breakers can fail to break. Then there are folks who plug a 1500 watt heater into a 16 gauge extension chord under the rug behind the couch.

But I love @ratio 's copper fuses... that's great!