Amperage?


I hve a breaker (switch) box in out apartment that has the single line switches marked as being 20 amps. The main breaker switch (the one that switches all of the lines at once) however is marked 15 amps. The wall outlets are 20amp Pro models made by Levitron (which I will be replacing as soon as I figure out if they should be 15 or 20 amp). My question is should I be using 15 amp power cords or 20 amp power cords, or, does it make a difference (my amps have 15 amp IEC connectors, I think), also what about the outlets themselves (15 or 20 amp)? I do not own or intend to own high power or current amps. I owm an SET and a Musical Fidelity 50 watt amp.
128x128dekay
Are you sure your main breaker isn't 150 amps?? I dont see how it could possibly be only 15 for your whole apt.(sounds downright illegal actually)Any way assuming youre only dealing with 15-20 amps, keep your cords to the high side to be safe.
as i understand it, the amp rating of the pc is not related to your household current but the amp into which it's to be plugged. certain amps (e.g., rowland, krell) use female mains sockets that require 20 amp cords.
Wino: The main breaker switch "in" our apartment is marked 15 amps while the single lines that it controls are marked 20 amps. Seems that it should be the other way around, but that's what I am dealing with. Our whole buiding had at one point been pretty much under code, so this does not surprise me. The box was replaced a few years ago and does not heat up at all nor have we have we thrown a breaker. I recently had an electrician in to repair the ground on one of the lines, but just discovered after the repair that the line still does not have a ground (when I checked it with the test light on a Monster HTS-2000 power conditioner after receiving a strong shock). The other lines however test OK for ground. I will check with the manufacturer of my amp to make certain that 15 amp cords are what I should be using (they are what I use now). Does it make any difference if the wall sockets are rated at 20 amps, when I am using 15 amp cords? I would just guess that they are just built to handle more juice but does this effect the sound at all? I had just noticed when shopping for PC's online that some (very few) are stated as being 20 amp models, which got me going on this. I then checked the wall outlets and see that they are marked 20 amps as well.
Dekay: The breaker is the "safety valve". It should have the lowest rating in the chain. The wiring from the breaker to the outlet should be rated to carry more amps than the breaker. Same with the outlet and your power cord to the amp. The reason for this is that if you have a breaker that is rated for....say....15 amps and your wiring from the breaker to the outlet is rated for....say....10 amps it is possible for you to plug an appliance into the outlet that draws....say....13 amps. In this case your are pulling more current than the wire is rated for and fire could result before the the breaker pops and shuts off the circuit. Like Winoguy I think something is amiss with your main breaker. Homes (an apatrments) built prior to somewhere in the early to mid 70's typically have 100 amp mains. Since then there has been a steady increase in the size of the mains and it is not uncommon for new homes to have 200 amp mains. Hope this helps. Good luck, Doug
Thanks everyone: It looks like the wrong type of box was installed and that I have more to concern myself than the sound of the stereo right now. I will give the landlord a chance to repair it granted that the work is inspected by the city as the last elecrical repair performed by the owner's electrician was not properly done either.
Dekay,sounds like you got a case for your city inspector to inspect.I know codes vary city to city. In LA an owner is required to pull a permit prior to undertaking/even installation of GFIs. / A service pannel?/you betcha.Once a permit has been pulled /inspection,upon completion of said work is required.I have the phone # you need;and a name to go with it/no menu maze. A standard wall ( 15 amps)receptacale is capable of 1875 watts.( this is why those hair dryers that draw 1500/1800 watts /combined with a light bulb, trip a breaker) The wire for a 20 amp circuit is the same, only the breaker is different. Records of any type of building permits, go back for many, many years.Even if your building is 50 years old they have the original blueprints, for sure.Electrical fires are a major concern;they'd be happy to come out to see what's what,and what was done without a permit.
Dekay,after rereading I want to add: Any 15 watt outlet has 2 vertical prongs. A 20 amp outlet has the same + the option to accept a cord plug that has one vertical and one horizontal prong. 30s are the twist lock/ 40's and 50s for stoves and dryers/AN upside down V and a large vertical blade at the bottom/ middle for the ground.
Avguygeorge, I need to question you on one point you made. You state that 15 and 20 amp service wire is the same. It is my understanding that most states electrical code require minimum 14 AWG for 15 amp services, and minimum 12 AWG for 20 amp services. Am I wrong in my understanding?
DeKay,in older electrical panels the amperage designation on the circuit breaker handle, which is usually highlighted with white or red paint,can partially wear off. It would be easy to mistake 150 amp for a 15 amp.If it is a 15 amp C/B then it is probably faulty, as under normal household operating conditions it would not be large enough to supply the branch circuits throughout the house without constantly tripping.In general,the max. C/B rating is determined by the ampacity of the wire which takes into consideration conductor size, type of insulation and ambient temperature.But if it is 150 amp the wire size should be much larger than the wires attached to the 15 and 20 amp branch C/B's.In older panels anything is possible.A lot of changes could have been performed by owner, tennants,handymen etc.I would have a licenced electrician check it out.
A 15 amp recepticle is rated for both a 15 and 20 amp circuit, so you can install it on #14 or #12 AWG.A 20 amp rated recepticle can only be installed on a 20 amp circuit with #12 AWG or #10 if rated for #10 AWG. Hope this helps.
Hi Everybody (as Dr. Nick says). I just checked the main breaker (stamped 15 amps) and it is not even wired into the system. The electrician just used the single line breaker switches that are marked 20 amps (this is a relief). The only thing to look into is that I do not beleive that the wiring is 12 gage (perhaps 14 gage) as some of the wall outlets are the type that accept the wire into a hole without screws (just push it into the hole and it locks). I was under the impression that these type of outlets were not designed to accept 12 gage wire (just smaller gages) but may be wrong on this. Anyway, I am not going to worry about it too much but will make certain that the box is up/downgraded to 15 amp breakers if it does not meet code. Sorry for the false alarm on the main breaker, but I do apprecieate all of the quick input. My wife lost everything, including pets, in an apartment fire in NYC years ago, which has influenced me anough to go through our electrical system piece by piece after discovering a cracked and water damaged wall outlet (which I would have never discovered had I not been involved in this hobby). I have just used the cheap Levitron Pro models as replacements so far (as needed), but will get something "nice" (maybe the Seymore & Pass model that Bob Crump likes) for the Hi-fi gear. I think that it's under $10.00. I will also follow the advise given and spec the PC rating to the amps themselves with the manufacturer's. If I am lucky in the process (depending on the wiring configuration) I may be able to get one "clean" line for the stero and probably use it for the digital stuff. Right now of the two lines available, one had the Fridge and the other the computer and it's external power supply. I opted for the computer line and just shut it down when I want to do some late night listening in the near field. I have a third "stray" line in the vicinity that just runs two overhead lights from what I can figure, but need to figure out where it travels throughout the walls. If I can pick it up before it travels through all of the light switches, it might make an improvement in the juice.
dekay, glad your wiring concerns have been dealt with. getting back to your original query and combining my first post with the second post of avguygeorge: some amps, like my big-box rowland, require 20 ampere pc's, since the female input socket on the amp is configured with 2 (bottom) vertical prongs and 1 (top) horizontal prong. the remaider of my current (no pun intended) electronics have the usual 3 vertical prong sockets that accept 15 amp pc's. BTW, fim sells all their pc's in 15 or 20 ampere configurations; naturally, the 20 amp models are significantly pricier.
Thanks again for the feedback. Kelly, your response clarifies the difference between the 15 and 20 amp PC's that I have seen listed as far as the end pieces are concerned. I have never seen the male of this species and had wondered about the additional slots (let's not get funny here) on the female receptacle.