New answers tagged electrical-panel
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You can use the 2-space panel as it is. Just split the hot so it connects to both lugs. However you must use a 2-pole breaker, or handle-tie all the breakers so they throw together. Why? You need a disconnect switch, and that's it! And it must be 1 throw action.
One of our crusades around here is to convince people that you are better off with a LARGE ...
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Yes, It's ok to connect both hot legs to the same phase. Obviously you can't use 240 volt breakers and won't have 240v there. But it is OK to connect both bus bars to the same phase (leg).
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Don't sweat the 3 blacks and 3 whites in the fixture. Those are so you have the option to power multiple bulbs off different circuits... say you have some circuits on a generator, you can put 1 of the bulbs on the generator-side panel. All the fixture blacks go together (in fact I would pigtail them on the bench before installing). All the fixture whites ...
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A non-contact yoltage detector is not a dignostic tool it is a safety tool. it will only tell you that a wire might be live. it will not reliably tell you that a disconnected wire is not live.
Turn off the power to this circuit (you can confirm that it is off using the voltage detector) connect the lamp to the yellow and white wires, turn the power back on,...
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It is acceptable to splice additional wire to a feeder, as long as that feeder is not an unfused conductor (service entry). Keep in mind that improperly installed splice can become a real nightmare. It might be better to try and raise the new panel up if there are no obstructions rather than try extend the feeder.
Also if an AHJ gets involved they may want ...
4
Sure. What you're talking about is similar to the "Electrician's Outlet"... an outlet right next to the panel which is fed by a dedicated breaker. So the electrician can plug in portable lights etc. when the rest of the house is turned off for maintenance. That's pretty much standard practice for interior panels.
The electrician's outlet just uses a ...
answered May 22 at 18:07
Harper - Reinstate Monica
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2
You can use a short nipple and mount the box (a water resistant or Bell box) right next to, over or under the panel , flex is expensive. I like going to the side because then the box and panel vertical surfaces don’t leak. You cannot use Romex because it is not rated for use outside. 1/2 “ nipple and thhn/thwn will be good in 12awg or 14 awg. 12 for 20 or ...
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Is your RCD 1P or 1P+N? The first only interrupts th live, the second both conductors.
If it's 1P you may have a residual current on the neutral leacking to PE making it to trip. An easy fix could be replacing the RCD with a 2P model
Also are you on TT earthing or TN distribution? If you're on TT your breakers must be at least 1P+N because neutral is ...
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Most circuit breakers only disconnect hot/phase. They do not disconnect neutral.
The problem is, somewhere in your handling of the wires, you managed to touch neutral to safety earth. Now, the electricity returning on neutralfrom other circuits has two paths: It can go back the normal way through the RCCB, or it can go via this circuit's neutral, to the ...
answered May 21 at 23:34
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1
An RCD (in any form) is always looking at the current going out vs the current coming back, which SHOULD be zero difference, so if they are different by the amount of your RCD (usually 10 to 30mA in your part of the world), the device trips. It might be that your type of meter is one that measures by looking at the potential difference by putting on a small ...
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If the light does flicker also if a hairdryer or vacuum cleaner
is connected to the same outlet/box as the garbage disposal, it is
likely a problem upstream the location where both circuits (light,
garbage disposal) are connected.
A loose connection acts as voltage divider in combination with the garbage disposal or any other big load. F.e. backstab
...
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The lever on the inside is a bypass
The lever on the inside of your meter can that you saw when the power company was working is what's known as a bypass lever that lets the power company take the meter out of circuit for service or replacement without interrupting the flow of power, which would be problematic for both you (power outage) and the utility ...
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If a swap reveals that the symptoms stay, i.e. other AFCI are also tripping in the same circuits, and all devices/lamps etc. were disconnected, there is most likely one or more problems with the panels/boards or wires.
Since the AFCI is tripping immediately, it seems to be a static fault and therefore an insulation tester would help to find the location via ...
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This is a very well documented problem with photos of the test configuration and multimeter values. Even the preferred soda (no sugar added, reducing health system costs) seems to be ideal best practice.
One central problem linked to the question is the very strange fact that most standard digital multimeters still do not have any mode or push button to ...
3
Broken wires don't trip breakers, they just cause outlets to stop working. An insta-tripping breaker means a genuine short circuit aka bolted fault. (lots of things are incorrectly called that, but this really is that).
I don't think the toaster oven had anything to do with it. IF it had failed immediately AND it had failed "open" (outlets stopped working ...
answered May 13 at 20:56
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5
Current flows in loops
Remember, current flows in loops. It's not like air, where you have the "hot" compressed air lines coming off the compressor, and there is no air return, it just dumps air wherever. With electricity there must be 2 wires to complete the loop, and both are equally important! We make all the fuss about the hot wire, but neutral is an ...
answered May 13 at 18:04
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1
You are correct.
There are several points in Article 725 that are not going to allow that to happen. This would give you no viable plan to rigidly separate mains from low voltage wiring, and that won't do.
Further, it would violate NEC 110.2 and 110.3(B) because you'd be defeating the UL-approved enclosure design, and using the transformer contrary to ...
answered May 13 at 5:38
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0
One mast, no duplex box, two meter-mains, no problem
The primary problem with your proposal as it stands in your post is that NEC 230.7 prohibits service and non-service conductors from being commingled in the same raceway or cable:
230.7 Other Conductors in Raceway or Cable. Conductors
other than service conductors shall not be installed in the same
...
3
I'd simply run the new neutral back to the "main" panel
While adding accessory ground bars to your "main" panel will be trickier than it looks, since you'd have to field-fabricate a replacement for the neutral tie strap that originally came with said panel in addition to unbonding the left-hand bar and moving all its ground wires onto a newly installed ...
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Inspector cat says No No No No No... Edit: Apparently Code says otherwise.
Returning neutral in the wrong place is a firestarter
Edit: Apparently this is allowed per ThreePhaseEel's reference, but still, I'd be happier if neutral were upsized to accommodate both sets of loads, for the below reasons.
A lot of people start out noticing that ground and ...
answered May 12 at 4:31
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0
Just an update.. before I installed the new outlet.. I tested voltage without any outlet.. voltage from black to white was 120 according to my multimeter.
Voltage from black to ground is 0.0 and white to ground just to check is 0.0.
Nonetheless my tester still beeps when held close to the bare copper wire.. technically I've been able to get it to beep when ...
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You will actually need a second driven rod to be safe with the metal pipe to the house being replaced. NEC 250.66(A) allows for #6 copper. Also, that rod is not fully driven. My jurisdiction requires the rod to be driven the full 8’. If you leave the old galvanized in the ground and it is in contact with earth for 10’, then you would not need the second ...
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In my neck of the woods (Pacific NW) we call that a "class 320" service: A single meter feeding 2 main panels. Because both panels are considered main panels, neutral and ground need to be bonded together. In the meter panel, in most cases, the neutral is already bonded to the can just by how the lugs are attached. I recently installed a class 320 service ...
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To close the loop: I contacted the electrician who did the installation. The lower lock tag can be removed.
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no no no, bad idea.
Anytime you twist 2 wires together, you make them better connected to each other than what they're attaching to. That sets the stage for a spectacular, lethal failure.
Also, the neutral bars are not rated for 2 neutral wires per hole!
So, this combo has trouble with its connection to the bar. Now, power returning on neutral can'...
answered May 10 at 19:49
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1
Garages are just the kind of place where you go through panel spaces like, as ThreePhaseEel says, a teenager through Mountain Dew. 240V power tool, boom, 2 spaces. EVSE, boom, 2 spaces. Double-stuff breakers aren't even an option because everything needs GFCI and/or AFCI (as of NEC 2020). I presume you are once bitten twice shy, and are eyeing a nice 30-...
answered May 10 at 14:41
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2
The starting point here is that your building does not have a Grounding Electrode System.
Every outbuilding is required to have one.
Your wiring has been done in the style of a separate service, even though it's more of a split service with the house. Not only does a service need a GES, it also needs a Neutral-Ground equipotential bond to peg neutral to ...
answered May 10 at 14:15
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8
understand the logic behind Bonding the Neutral and Isolating Ground
the green earth ground or bare copper always connects to the metal of the panel box, or any metal that you touch.
the [white] neutral only connects [bonds] to the green earth ground connection at the main panel.
in any sub panels wired from the main panel you isolate the neutral from ...
5
The steel chassis of a service panel is always grounded.
You can identify the neutral bar because it's designed with at least the ability to be isolated from the chassis. Hence the standoffs and fiber guard to prevent bare wires from hitting the chassis.
You can identify the ground bar because it is irrevocably bonded to chassis.
The screw that the ...
answered May 10 at 2:52
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18
Whoever wired this panel simply was not paying attention
The installer who wired this panel did not pay attention to the schematic on the label, assuming that removing the bonding strap was enough here. However, the split ground design of these Murray panels means that the left-hand bar is factory bonded to the case, with the right-hand bar being the only ...
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Are you a renter?
I'd call your utility and pretty please ask them why they might have sealed your customer shutoff. Send them the photo.
Otherwise... you don't have a main breaker (if that's what's not in the little box) and I'd be very, very scared.
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The shop has it's own power and own meter? That's really neat- probably cost him a penny too!
The neutrals and grounds don't have to be separated then. Still surprised there's not two bars on either side though.
OK on to your question: When you said the wire was 'hot' I'm assuming you mean 120V on it. That's troubling, obviously. Worse is nothing blew. So ...
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The #2 reason for a wire size bump is a long-distance run (>70 feet @ 120V; > 150 feet at 240V).
The #1 reason for #10 on 20A circuits is aluminum wire.
Note that copper-clad aluminum is a thing - that looks copper from the sides, but looking at the end of the wire you will see the gray of aluminum. The metallurgy will also be stated on the cable sheath ...
answered May 9 at 17:39
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2
If copper, no problem, easy, yes you can use 12Ga copper to add to it, it was just overbuilt. Using larger wire than required is fine, code only specifies the minimum size required.
Do make sure you use wire nuts (or other wiring connectors) rated for the combination and number of wires you use. There is normally a little table on the container listing ...
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Use bare copper ground wires.
Grounds don't need insulation, so don't waste the fill.
Consider using copper feeder.
Copper? For feeder!!?? Weird, I know. Copper is expensive and a poor conductor by most measures. But when conduit fill is the scarce commodity, volume is the measure that counts - and by that measure, copper is the best conductor on ...
answered May 8 at 18:10
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1
Best option is to disconnect the incomers, e.g. to ask the supplier if the breakers are not accessible. If that is not possible, these live saving points may help:
Only when a second person is around this kind of work should be done. That person must be informed about the kind of work and has to be aware of the danger to help a person that is touching live ...
2
Stay away from the metal parts above the main breaker. They are hot always.
If you haven't turned off the main breaker, also stay away from the bolts and buses right below it, and the buses down the middle that the breakers clip into will also be hot.
It helps to use gloves if you can get PPE in this day and age.
Note the way the last guy runted off all ...
answered May 7 at 6:41
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0
It's a trade of as far as safety goes. If the ground is bonded to neutral, and there is an an open neutral situation, or lightning strike, or utility transformer primary to secondary short, all your grounded appliances like washing machines and pool pumps can become live with dangerous Voltage, since your ground rod or water pipe likely has too high of a ...
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After thinking about it and commenting on Harper - Reinstate Monica's answer I realize it is a trade off. Utilities may not be required to ground the secondaries on their transformers in all areas, or that ground could be faulty. They might be relying on many buildings providing a grounded neutral to blow their high Voltage fuses and keep the secondary ...
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Paralleling subfeed lug blocks is an option...
While the THLK2200 indeed is only supported by PowerMark Gold loadcenters, there is nothing that prohibits one from putting subfeed lug blocks (as opposed to actual breakers) in parallel, provided they support attaching large enough wires (1/0 or larger), and the attached wiring obeys the NEC rules for parallel ...
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A 60 amp sub can be grounded by #10 copper per 250.122 the main panel should be #6 to the rods / pipe electrodes , you say the ground is undersized without specifying what is there and or exactly how the system is grounded and the year it was done , in 99 there are were major changes to grounding and bonding.
Back when the home was built only the main panel ...
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The main panel appears to have a nice fat braided ground on the ground rod.
For the 60A subpanel and 50A A/C service, a 10 AWG ground wire is perfectly adequate. Not seeing the problem.
The 30A sub is a Zinsco, which some very serious fire-starting problems with its buses, which can't be fixed by swapping breakers. Since it appears to be configured as ...
answered May 4 at 3:52
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0
If the conduit is metal and continuous (and properly assembled)
any green ground wire is an extra.
No green wire at all would be an adequate ground, as metallic conduit is a grounding conductor (with a possible exception related to pool equipment?)
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That plan looks fine and normal. They don't like top entries because real-world, they leak.
I myself prefer a "drip loop" as it were, where I enter the bottom of both boxes, with an LR and LL right next to each other.
You must use something like #8 THWN wires. You can't use NM-B obviously. And you cannot use #6/3 UF-B, because UF-B is thin and wide, ...
answered May 3 at 19:46
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1
Being a grid-tied installation, it's quite possible that the power utility had some say in which phase to connect the PV system to. In 3 phase systems, it's necessary to balance the load as equally as possible between the 3 phases but this is difficult to impossible to do within a single household. So the utility designs the distribution network so that a ...
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You need to evaluate which phase has the highest average load during the daylight hours and put the system on that. If all your loads were 3 phase (I know they are not) having a single phase solar feed would create imbalances in the system.
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Why not run conduit?
I noticed first that you seem to be wanting to direct bury your electrical cables; this is a massive mistake upfront, as renting a trencher to rerun cable costs a lot compared to the cost of throwing Schedule 40, or even Schedule 80, PVC in the ground vs. simply slapping a direct bury cable in there. I would run 2" PVC conduit (...
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You'll need conduit for the whole run, but that means you can use 6AWG wires
You will need to run conduit for this entire run; loose wires by themselves just won't do as a wiring method (see NEC 300.3(A) for the reference on this). However, this means you can use 6AWG THHNs (/THWN, since the stuff you get these days is all dual-rated anyway) for the hots ...
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Stop. You're making the classic novice mistake.
I'm referring to sizing the subpanels.
Ever bought tires? They come in different speed ratings. Have you ever gone "My truck has never gone faster than 85 mph, therefore I can't use an HR rated tire"? Of course not. The fact that it's good for 112 mph, you see that as safety margin. Am I right?
Well,...
answered Apr 27 at 18:01
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The number 2 wire at those distances for anything more than a 60 amp load, will have a large voltage drop. The 300’ and 275’ 60 amp will work with the voltage drop being 4.4% this will work , it is above the recommended 3% but also at full load for those distances. Number 2 aluminum is two small for a 100 amp service. You will need to bump up to 1/0 aluminum ...
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