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hobbesmaster posted:I guess we can't have a power megathread. Dispatch, arc flashes, all that jazz. I wonder how many power engineers there are even here. Anything under 480/277V isn't real electricity.  I'm not sure if it would be good to have it in DIY - what other forum could we put it in? GBS? Back to 120V - electricity can be weird. It's not like a bullet from a gun where getting hit in the head will almost certainly kill you. There are a ton of variables that play a part, particularly the path of the circuit and your body's resistance. It's foolish (to a point) to just point at the voltage level. (That point involves safe working and approach distances. Under 1000V the approach distance is simply "avoid contact". At 138,000 volts, no point of your body can be within about 3'6" of the electrified line, and believe me, I'd want to be a lot farther away from a 138K line.) A simple change in skin resistance from sweating (say working on a 120/240 breaker panel in a cool room versus doing the work in a 110F foundry) could change an irritating shock into something much more dangerous. I've done work on 480V systems up to 4160V systems, but I still show 120V the respect it deserves. Three-Phase fucked around with this message at 02:46 on Mar 14, 2009 |
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Mar 14, 2009 02:25
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Temporary Overload posted:All of the large drillships and semisubmersible rigs in the gulf use 480v. Stupid thing is, the equipment runs just fine on 480v if you up the varistat breakers from 25A to 30A, but if something breaks while running on 480, it voids the warranty. I take it that using step-up autotransformers would be against whatever code governs these vessels? I know there are a lot of limitations to residential/commercial/industrial use of autotransformers.
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Mar 16, 2009 00:03
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hobbesmaster posted:Is this because if the insulation fails you have more problems than with a regular transformer? Or is it something else? Sort of. A transformer with two separate windings has intrinsic isolation - the transformer's core limits the amount of energy that can pass through if there's a fault on the secondary side. You don't really get that with an autotransformer. I believe that you can use autotransformers for a few things, like if you have a building that's got 120V/208V (4-wire three phase) power system and you need to power an air conditioner that runs off of 240V, you can use an autotransformer to step the 208V to 240V. (Also, the NEC says you cannot derive a branch circuit from an autotransformer. I need to check some details as to what's OK with the NEC and what isn't. Sadly my codebooks are at work.) hobbesmaster posted:There are computers to do matrices and newton's method, why do professors have to take them away?! I've used SKM Power Tools - you can do stuff like arc flash analysis, fault currents, and my favorite, breaker/fuse coordination studies. It even makes those nice trip curve diagrams. Three-Phase fucked around with this message at 02:50 on Mar 17, 2009 |
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Mar 17, 2009 02:35
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chedemefedeme posted:Edit: I love reading up on things. This somehow lead me to come across the power conditioning and transitional quality advantages of double-conversion constantly on-line UPS units. Unfortunately it seems these are harder to come by. They arent hugely more expensive but I cant find any on newegg?! I saw a small double-conversion Eaton unit (like 2kVA) at work. I think they cost several hundred dollars. The UPS units I'm typically around are double-conversion, 208/120V or 480/277V units with a separate battery storage cage storing a hundred or so jars, and the units are rated from around 50kVA to 250kVA. Ah, that's the nice part of running medium and high voltage circuit breaker logic and trip/close coils on 125VDC. No UPS needed, just a battery charge controller. Three-Phase fucked around with this message at 12:37 on Dec 28, 2010 |
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Dec 28, 2010 12:32
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some texas redneck posted:He also installed outlets outside - one has wires outside of conduit (all purple THHN, looks like 16 or 14), all of them are GFCIs. One used to constantly trip every time it rained, it no longer works at all. I have no idea what breaker it's on, so it's kinda hard to kill power to it without taking down the whole house. I think you can buy 120V tracers were you plug in one unit at the outlet, and then you can use the other half to determine which breaker feeds that outlet. Or it could be as simple as getting a buddy, a voltmeter, and shouting back and forth "IS THAT IT?" "NO!".
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Jan 1, 2011 00:02
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grover posted:Something like this would be fine: Probably not a big deal for folks working with 24VDC and up to 240VAC, but... That flimsy-rear end thing goes to 1kV DC and 750VAC? I'm amazed that this thing is listed as being a Cat-II device at those voltages. (The category ratings (I, II, III, and IV) refer to the ability of the meter to protect the user from transients.) Still should work fine for 120VAC. (If you have $500 to blow, I've always liked the Fluke 87. Worked great with the 3000A current clamp.) Three-Phase fucked around with this message at 05:06 on Jan 23, 2011 |
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Jan 23, 2011 04:54
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grover posted:The Fluke 87 would probably only costs about $3 to manufacture, too, if not for the calibration and testing. The high-speed fuses alone for the 87 cost more than $3, the 11 amp one is about $9 on Amazon. But yeah, they've got to do a lot of safety testing and engineering to say "this thing is safe under category IV conditions at 600VAC and cat-II at 1000VAC." They have some nice features too, like the beeping and displaying LEAD if you are plugged between COM and 20A and switch the unit to volts. I sort of preferred the Dranetz approach of having a physical window where you simply could not plug into the current input when you select to measure voltage. The Fluke 115 is pretty nice and only $175 ("only" in respect to $500 for the 87). Again, probably not necessary for home users unless you're doing a lot of electrical stuff. Most homeowners don't really need a True-RMS device or the capability of measuring frequency with their meter. Fluke sells a Volt-Alert pen that you can get for about $25 at Sears, it's worth every penny and apparently has saved a lot of lives. Anyone thinking about electrical work (on home AC systems) must get one of these. (At my workplace, though, we have a lot of 125VDC systems that cannot be detected by these pens.) Three-Phase fucked around with this message at 14:37 on Jan 23, 2011 |
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Jan 23, 2011 14:33
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Has anyone mentioned ECN's Violation Photo Forum? It's got a ton of really great examples of things not to do. Ever.
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Jan 23, 2011 14:40
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Nemico posted:I've been selling a lot more of the Fluke 28IIs over the 87Vs since they introduced them. Nah, I was meaning a non-contact sensor that could detect DC. Where I work, we have large circuit breakers, a little smaller than a washing machine (typically 2400V or 7200V at 1000A or so, depending on the breaker type and size). Inside the breaker compartment, all the controls like the trip/close coils are run off of 125VDC, +62.5 to ground and -62.5. Then all your protective relays and metering (SEL and GE Multilin) also run off 125VDC. tworavens posted:http://www.youtube.com/watch?v=c_F3x5rAJpE Good video. I was doing some measuring at work on this. I've seen UPS units that put out lovely sinewaves with 3% THD, and then I've seen some ugly bastard systems that put out butt-ugly waveforms. Harmonics suck. One thing it looks like he missed was systems that USE SCRs. Those act as a controlled diode, like a one-way gate you can "fire" and it lets a section of the sinewave through. If you have a dimmer switch at home, it most likely uses two SCRs. It's simple and efficient, but due to the very rapid dv/dt, it also creates a ton of harmonics and radio noise. Three-Phase fucked around with this message at 01:09 on Jan 24, 2011 |
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Jan 24, 2011 00:59
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chedemefedeme posted:Neighbor: Holy crap! An electrician said that it would be normal to have 220V at some 120V outlets? You don't simply tighten things at random to find where a problem is occurring; You work your way through a circuit until you pinpoint what's causing the problem. I agree that this sounds like the neutral circuit is broken. I would say that this might be a dangerous "electrician" that isn't trained or bonded (carrying insurance).
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Jan 31, 2011 01:43
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babyeatingpsychopath posted:Aluminum is still also very very common for feeders, 250MCM and above... I've seen bus bars that were aluminum - I think 3000A capacity. However I've also seen places that won't permit any aluminum conductors or busses. tworavens posted:I've heard that they get more sensitive to trips with time, and that when they fail they should fail open. That is to say you won't be able to reset the breaker after a trip. Mostly they do just this. I've seen molded-case single-pole breakers that seemed to nuisance trip over time, especially when they were continually used at/near their capacity. The solution was to install properly sized breakers, as well as upgrading the wires fed from the breakers. (You cannot just slap in a bigger fuse/breaker without inspecting the wire size to make sure it's properly protected by the new breaker/fuse.) As far as capacity goes, unless they are 100% rated, breakers should not continually draw more than 80% of their rated current. I believe the fail-open standpoint is correct, but breakers had been recalled in the past for failing to open, overheating, etc. Mechanically most breakers have what is called a "trip free" design. That means that even if the handle is mechanically blocked or fails in the closed position, the circuit breaker will still trip and open the circuit. By the way, beware counterfeit circuit breakers! I've seen warnings that span from your standard 20A single/dual pole breakers all the way up to three-pole molded case breakers in the >100A range. Counterfeit Square-D Breakers Counterfeit Eaton Breakers Motronic posted:Most standard (non GFCI, non arc fault) breakers are thermal. If you've just tripped it, it's still warm and won't take much to trip it again until it cools down. For the folks interested learning about this, to my knowledge there are a few types of trip units: 1. Thermal (as mentioned by Motronic) 2. Magnetic (picks up from a sudden surge of current caused by a short-circuit somewhere past the breaker) 3. Thermal-magnetic (breaker that has both trip units) 4. Electronic (looks at current from a set of current transformers, has a little computer that signals to trip if there's a short or overload. More sophisticated protection relays also look at voltage, but those are typically for really f-ing big electrical devices. Typically not seen in residential/commercial stuff.) Three-Phase fucked around with this message at 15:00 on Mar 5, 2011 |
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Mar 5, 2011 14:38
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I've seen stores where I live that seem to specialize in luminaries and lamps, but I'm not sure if a place like that could replace a fixture. Have you checked some larger hardware stores?
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Mar 8, 2011 11:52
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Video is dead, it seems. Here goes nothing! 
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Mar 12, 2011 15:23
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tworavens posted:Kind of an off topic question, but important to electricians and electrical engineers. Anyone here have some red-green color blindness? I do. Its not that I can't tell the difference. The only time I ever have any problems with it is occasionally with resistor color codes I mix up a red and a brown. I don't even have problems with telephone wires. The problem with red/green is that red is a common "hot" wire color, and green is almost always a ground color. In more places green with a yellow stripe is used, so that may make it easier to differentiate ground from hot. (Sometimes you also have a safety ground and a separate isolated ground for sensitive devices.) If an electrician got the hot and ground reversed, it could do some nasty things like electrifying a metal chassis of a device. For the US, these are the common colors you need to differentiate between: Black/Red/Blue (three phase) Brown/Orange (or violet)/Yellow (also three phase) White/Grey (neutral) Black/red (hot) Green/Green-Yellow/bare copper (ground)
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Mar 20, 2011 04:29
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Ugh, backstabs. You've got copper wiring too, right?
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Apr 27, 2011 04:52
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quadpus posted:You'd love this then That's pretty drat bad.
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May 6, 2011 00:55
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Motronic posted:Are you positive your equipment won't run on 208? I've only run across very very few things that need to be either 208 or 240 (high end and quite old UPSes....think nasty early 90's filing cabinet sided Lieberts). I don't have my codebook here, but I believe you can use an autotransformer (aka a buck/boost transformer) to boost 208V (line to line, two pole) to 240V L-L. I also believe that you can not use an autotransformer for any larger change in voltage such as 120V to 277V, 277V to 347V, etc. (E:F;B) How many kVA or MVAs are you talking about here? If this is a really substantial load, my concern would be pulling too much current on two of the three phases. (I believe a Scott-T transformer configuration would allow you to go from three to single phase while staying balanced.) Motronic posted:nasty early 90's filing cabinet sided Lieberts). Lieberts... I think I stumbled across one at work. (Now more people are getting stuff like Eaton Powerware 9000 series for 120/208V and 277/480V UPS's.) Three-Phase fucked around with this message at 04:09 on May 12, 2011 |
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May 12, 2011 03:58
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grover posted:There are certain cases where a larger or smaller neutral is prudent, but you're not using those kinds of loads. I think if you have a lot of harmonics (esp. zero-sequence harmonics), you can have problems with the neutral overheating unless it's oversized, but that's nothing a person will see in a home.
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Jun 4, 2011 20:54
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grover posted:heh, like that will do jack-all if your house is hit by lightning. One of the motors at work has a lightning arrestor setup in the stator lead compartment, connects to the two lines going to each phase. I'm not sure if it's arc-gap or MOV. I believe that in the event of a lightning strike, it would take the affected phase to ground, and the Multilin would see that sudden changes in current and voltage, and trip the circuit breaker for the motor due to a ground fault/voltage imbalance/phase loss/current imbalance. Don't forget that on HV transmission lines, you also have an upper wire that's there to (hopefully) grab the lightning instead of having the lightning conduct to one of the phases. (There's a school of thought that the line protects a 90 degree area under it, and another school of thought that indicates the protection area is like the space under two touching circles.) dietcokefiend posted:
Power lines also have recloser systems. So if there's a fault, the breaker opens, but then closes after a second in case whatever caused the fault (lightning strike, fried squirrel/bird, etc) has gone away. It'll try this a set number of times, then give up and fault out. A large number of faults on lines are temporary, so that makes things easier for everyone involved. grover posted:Motor protection is a voodoo science unto itself. Breakers and fuses have different trip curves, and often must be used in conjunction to properly protect a piece of equipment. It can get rather complex and is often a specialist field. You can't just use any fuse that fits, either, as there are different types of fuses, even within the same current rating. You have to go through the documentation and see what the design engineer specified. Heh, I just use CAPTOR in PowerTools to draw and coordinate time-current curves. (We need a combination of  and .)
Three-Phase fucked around with this message at 13:41 on Jun 12, 2011 |
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Jun 12, 2011 06:32
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kid sinister posted:Attach that white wire to the grounding screw at the upper left. That little wire is what grounds the case for washers. Should he remove some of the paint on the surface before he attaches the ground screw - better ground conduction path?
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Aug 2, 2011 10:13
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Ok, I've got a question about a mystery piece of equipment: I was at a large public swimming pool awhile back, and it appeared that the outlets around the pool didn't have individual GFCIs or indication they were GFCI protected. However, at one end of the pool were two wall plates that had an intermittently flashing indicator with a key switch reset and something like "PANEL 22 PH 1" and "PANEL 22 PH 2" on the other. The flashing indicator had something like "alarm" on it. I'll see if I can get a better description - for obvious reasons this is in an area where cameras are probably not a good thing to carry around. I'm wondering if those are some kind of older GFCI system for all the outlets around the pool. There was nothing on the panel that explicity indicated or hinted at their purpose. I'm assuming they were GFCIs. babyeatingpsychopath posted:Dude, I think that switch looks fine, however this switch is HP rated (for motor use). Get that switch and a motor-rated ON/OFF toggle and you're set. Even a "spec grade" 15- or 20A snap switch will work for this application. Square D 30MM maintained rotary switch with 240V 10A NO/NC contact block. The industrial standard (if you're cool with spending $90 on a switch). (Legend plate sold separately... probably another $10-$20.) grover posted:And yeah, they're full of crap about the rating. Motors draw a LOT of power on startup, it's damned-near a dead short fault until it starts spinning, so it just means the switch has to be beefier to handle the current than you'd need for, say, a light bulb. Doesn't mean it's impossible to design for. FUN FACT: I had a medium-voltage motor that had about 300FLA (RMS). On startup the peak asymmetric current was about 4000A peak, about 2800A RMS. That was the component caused by the subtransient reactance, as the motor started to roll it dropped down to only a thousand amps or so until it was up to speed and synchronized. It makes such a lovely sound when it starts.
Three-Phase fucked around with this message at 15:55 on Jan 12, 2013 |
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Jan 12, 2013 15:28
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I don't have my codebook handy. Does that table for grounding also apply to installations over 600V?kid sinister posted:Insta was recommending to use that a 5V DC wallwart as the signalling voltage to control the relays. 5 volts DC is kind of a standard for electronics. drat near everything uses 5V DC, down to USB connections. If you're talking about control relays (not like the tiny ones soldered onto circuit boards), usually the minimum voltage for the coil is 24VDC, at least that's what I've seen. This is coming from a more industrial-oriented standpoint. I'm personally a fan of 24VDC for controlling relays and logic, but a lot of places just straight-up use 120Vac. Three-Phase fucked around with this message at 09:15 on Jan 18, 2013 |
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Jan 18, 2013 09:11
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babyeatingpsychopath posted:That's a good point. The ice cube relay selection pages in my catalog have columns for 12VDC, 24VDC, 24VAC, 120VAC, and 240VAC coils, all with 600V contacts at various (1-10) amperages. That's an industrial control catalog, and all those plug into socket bases. You can also get some in 120VDC. Those are a bit less common. I've seen a lot of 120VDC for the control power system for things like medium voltage circuit breakers. (Operating the coils that close and trip a 13800V, 1200A vacuum-bottle circuit breaker. Not too big, about the size of a washing machine.)
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Jan 18, 2013 22:51
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Cat Hatter posted:I have a fan that I'd like to control with a footswitch designed for Christmas lights. The switch is rated for 500 watts incandescent load and I know electric motors are different but my fan only draws ~50 watts so a 10:1 safety margin should be more than adequate, right? I would recommend calling an electrician to look at it as soon as possible.
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Jan 22, 2013 23:02
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Discolored insulation may likely mean overheating of the conductor. A poor connection or overloading can cause this.
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Jan 23, 2013 23:41
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EDIT: Forgot about how residential outlets are wired in parallel. So that would explain how the outlet had heat with no load plugged into it. If you do kill power and open it up (first, confirm that you killed power before doing any work!), you can touch or even gently tug on where the wires connect to the outlet. If there's a wire around a bolt or a backstab you can easily pull out, congratulations, you've likely found the problem. Look for any discoloration or worse, charring. If you smell anything odd, that could be important as well. If any of this gives you pause, simply turn off the circuit at the breaker and call an electrician. Three-Phase fucked around with this message at 04:43 on Jan 26, 2013 |
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Jan 26, 2013 04:37
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I think I agree. But there's something else here I missed when I read this the first time: Something worth noting is that one of the appliances was a vacuum cleaner - a vacuum cleaner that probably has a little induction motor in it. For a resistive load like a heater, if you reduce the voltage, you'll porportionally reduce the current - Ohm's law. For an induction motor, if you decrease the voltage, the current draw will increase. The motor's power factor will lag, and you'll be putting in more current to do less real work. Depending on the design of the motor, a ten percent reduction in voltage means a ten percent increase in current. More than ten percent and the current can start to sharply increase. So if you had a bad connection in there, that would drop the voltage to the motor, cause the motor to draw even more current (despite the bad connection limiting the current to a small extent) and then the breaker would trip. My guess is that the kitchen outlet doesn't have this problem, and the current draw from the motor is well under the trip curve of the breaker. FUN FACTS: As far as the trip curve goes, the circuit breaker has a thermal element and a magnetic element. The magnetic element trips INSTANTLY once a certain large amount of current is passed, in a short circuit. Like for a 20A breaker that might be 400A for less than a sixtieth of a second. There's also a little strip, like in a thermostat, that trips if the breaker is exposed to a lower current for too long - an overload. Like Grover said, the lower the current, the longer to trip - like this for a 20A breaker: 16A (80% rating) - never trip 25A - trip after one hour at 25A 40A - trip after one minute at 35A 100A - trip after one second at 100A The delays allow for intermittent overloading and the massive current inrush associated with things like energizing motors and transformers. (These are gross approximations of points on the overload section of a trip curve.) This PDF from Schneider gives a good example of a trip curve. The long part at the bottom that's less than 1 cycle in duration is for the short-circuit pickup (ANSI 50). The long curvy part is the inverse-time current curve (ANSI 51). Fuses are also typically built with an overload element (like a spring clip) and a short-circuit element (all these little sections that vaporize in a short circuit). On the equipment I use at work, we have relays - nowadays these are little industrial computers that monitor the current flow indirectly (with a current transformer for 50/51 protection) and signal for much larger breakers to open. Three-Phase fucked around with this message at 05:10 on Jan 26, 2013 |
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Jan 26, 2013 04:52
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Check this post out: Wrong ways to wire an outlet It's easy to make a crappy connection here.
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Jan 26, 2013 14:15
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So I take it the wire was loose?
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Jan 26, 2013 20:57
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You're putting mogul bulbs in your garage?  
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Jan 27, 2013 01:31
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Shoot, I thought that base was mogul - the 600W and 250V threw me off.
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Jan 27, 2013 05:24
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Hazed_blue posted:I think there must have been some sort of internal failure going on, because the wires were not loose at all. I was chatting with my father on this, and his comment was "Backstab outlets are awful, I don't know how they ever thought that was a good design..." and so forth.
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Jan 28, 2013 02:37
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Is it possible that an electrical transient tripped both GFCIs?
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Jan 30, 2013 22:52
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Tim Thomas posted:Panduit raceway like that is really intended more for LV wiring in an enclosure or on machinery what have you than what you're using it for. Ah, Panduit. A staple of modern cabinet design. It's great for segregating signals in a cabinet too - like you can have sections for small signals (0-10V, 4-20mA) and other sections for 120V I/O. Fun fact: Unless you're delivering a cabinet to a customer, it seems like nine times out of ten a system is installed with Panduit covers, then the covers come off to do modifications or troubleshooting, and are never replaced. They're just such bastards to get back on the channel. Especially when you have a channel packed with a hundred wires. Still makes life a lot more manageable than really old cabinets where wires were bundled together in massive looms. Three-Phase fucked around with this message at 15:27 on Feb 2, 2013 |
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Feb 2, 2013 15:25
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If you want to efficiently change the speed of an AC motor, you need to change the frequency, not just the voltage. What will likely happen is you can slow the motor a little bit since induction motors have slip, the current draw will go through the roof as the motor stalls, and then you'll trip the circuit breaker. The motor is probably not designed to operate with that much slip.* A rotating motor generates counter-EMF. When the motor starts it's like a short circuit, but as the motor rotates that counter-EMF reduces the current draw from the motor. * - If you have a large synchronous motor, like they have in industry, any significant amount of slip is detected and will probably trip out the exciter and knock the motor offline. EDIT: on a bathroom fan, if it has a little "shaded pole" motor, it might be possible, but check the specifications on the dimmer switch. If you set it too low, the motor will stall and trip a breaker. I think that fan speed controllers are like dimmers but don't allow the voltage to go so low that it stalls the motor. Three-Phase fucked around with this message at 11:43 on Feb 4, 2013 |
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Feb 4, 2013 11:38
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XmasGiftFromWife posted:If you have a shop vac I would suggest just creating a small port to attach the vac hose and a couple of bleeder holes to control the suction. Can you use standard furnace filters? you would only need one level for the floor. I'm not trying to be a problem here, but aren't you not supposed to vent flammable vapors through a shop-vac or blowers that aren't meant to ventilate out flammable vapors?
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Feb 4, 2013 22:30
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XmasGiftFromWife posted:Yep, my brain was elsewhere. I was thinking only of air flow, not the need to ventilate. I had not acknowledged the fact the material is flammable. This also makes me think for safety As far as 2, I don't see the issue in venting to your driveway, unless Bad Munki is somehow painting an entire SUV in that little 2x2x2 box. I'd want it to be away from any running engines. Plus it would suck to get paint on someone's car! As far as venting back into the garage, if you're doing a ton of painting and the garage is small, you might be able to build up an explosive (or toxic) atmosphere in the garage. In that case, venting outside would be a much better idea. Yeah, the thing that worries me, again, is that either solution you're pulling potentially explosive vapor mixture past a fan, which probably has some kind of exposed motor on it. Brushes in motors can easily produce sparks. I wouldn't expect a normal AC squirrel-cage motor, like in a fan, to ever produce sparks unless there's a fault. But if it does fault and spark, it could cause a (hopefully small) explosion if it has vapors around it. Plus that blower will only operate when there's a presence of potentially explosive vapors. Also, I'd be concerned if there were bearings that could heat up to the flash point of the vapor you are sucking out as well. Not sure how possible this is. I'm looking for a solution on Grainger, but I'm having trouble finding something that costs less than $1000. Be sure to keep electrical stuff like cord-and-plug 120V out of that box when you're paining. Three-Phase fucked around with this message at 03:17 on Feb 5, 2013 |
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Feb 5, 2013 03:10
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I'd say whatever you do right now, don't run fumes through a vacuum cleaner or you could have an explosion. I was wondering if you could use shop air from an air compressor to do any of this, but what you're describing is a situation where you need a vacuum. I have seen some air-operated vacuum pumps. If you have an air motor, unless you have something wacky like a bearing overheating, the electrical spark issue goes away. Could something like this be safely re-purposed to vent out fumes? Three-Phase fucked around with this message at 03:29 on Feb 5, 2013 |
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Feb 5, 2013 03:25
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Triplex 500kcmil, 15kV class - I think that's rated for 90C or 105C terminations. I think the nominal bend radius for that is at least eight feet.
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Feb 14, 2013 03:13
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This is what's so nice about medium-voltage plant distribution. I can provide 1MVA at 480V with 1200A, or I can provide it at 4160V at 138A. Especially motors >500HP. I've seen diagrams showing 480V 500HP motors, those must require an absolute shitload of copper. babyeatingpsychopath posted:Interestingly enough, at the scrapyard, 500kcmil has been about a gallon a foot for a dozen years or so. A foot of bare 500 will buy you (roughly) a gallon of gas, at scrapyard prices. It costs about triple to 5x that to buy from the supply house. I've heard people are trying to steal copper from substations now. That's crazy. Three-Phase fucked around with this message at 21:48 on Feb 14, 2013 |
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Feb 14, 2013 21:45
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