Electrical Help Needed

[horn1004]

Sorry to do this, but I want to make sure somebody can help. Please see this thread- http://archive.reefcentral.com/forum...96#post1625396

[Chamkeeper]

Im not sure I completely understand what you're looking for but here's my $0.02. First, rather than buy all those small boxes I would buy a box that can hold four or six outlets, its the same size just longer the the individual boxes. As far as wiring goes, the GFCI has to be the first to connect to the source, after that, the neutral (white wire) to the other outlets will come off of the blue (typically) on the GFCI outlet. Wiring in this fashion will make all of the outlets GFCI protected.

Please post a specific question so we can offer a more direct answer.

[horn1004]

Well, seeing as how I've already got everything built and wired, that's not a possibility. I've already got all the outlets wired, except for wiring the power cord to the line side of the GFCI's. That's not my problem. My problem is that I need a power cord to plug into the wall that is rated for 20A. The GFCI's are rated at 20A, but I can't find a power cord which is 20A. The highest I can find is 15A. I guess my specific question would be, Would using a power cord rated at 15A for a 20A GFCI outlet be acceptable?

[areefer]

You can use a regualar 15A power cord on your outlet. The GFCI will trip if there is any problem. Most practice is the use the same rated wire for the breaker so the breaker will trip before the wire melt. The power cord should be rated for the device that you are using. If you are pulling more than 15A for one device then I would recommend that the power cord should be rated higher than 15A, unless it is a motor where the inrush current draw is high but you don't have to use a higher AWG wire. I hope this help.

[areefer]

Oops, I just re-read the post and just realize that you want a power cord from the GFCI to the wall. If this is the case then you must match the same AWG wire to the wall. But my ? to you is your wall rated for 20A.

[horn1004]

That's a question I can't answer because I'm not setting the tank up until I get settled wherever I move. If it helps any, this is what I'll be running on the system
Ampmaster 3000
Mag 24
3 250w electronic MH ballasts
3 110w electronic pc ballasts
Sedra 5000 for skimmer
heater
possibly 4 maxijet 1200s
possibly wavemaster pro

I really do not plan on using all 20 outlets. They're there just in case I need to plug in a light or something like that. The idea behind the 4 seperate cords is so that I can put the ampmaster on a seperate gfci, along with the mag24 and the MH ballasts each on a seperate gfci, so that if one pump causes its gfci to blow, the other 3 won't blow as well. I want the cords to at least be 10ft in length so that I can possibly not have to put all the load on one circuit.

[kgross]

Use a cord rated at a higher current than the breaker will trip at. That way the cord will not fail before the breaker trips.

Kim

[Zephrant]

Find a 12 gauge extension cord, and cut the end off of it. 12ga is rated for 20 amps, 18ga is rated for 15 amps. Any HD should have a large verity of extension cords in the 12ga and even 10ga range.

If you can, it is really nice to have two separate circuits going to a tank that size. Then if one breaker fails for any reason, you still have some circulation going on. Make sure to split your pumps to separate circuits if you can.

Zeph

[areefer]

Actually 12AWG is rated for 20Amp and 14AWG is rated for 15Amp.

[Dallas_Joser]

Is the breaker supplying that room a 20 amp?

A 12ga cord should work and home depot sells them.

If you breaker is rated for 15 amps then you don't need 20 amp cord as the breaker will pop at 15 not 20.

20 amps is just the max that each GFCI can take.
Just because you have 5 GFCI does not mean you can put 100 amps on that circuit.

See what the main breaker rating feeding those GFCI's is and then size you cord accordingly.

[scott324]

Horn,


Your best bet is to divide each of your outlet banks on two seperate circuits. With the appliances listed you are pushing the limit for a 20Amp circuit, and exceding it for a 15. According to the NEC (Nat'l Electric Code) you can only draw 80% of the breakers rating if the load is continuous. i.e. If you have a 20A circuit you can only draw 16A continually. That works out to around 1700Watts and you are pretty close with my rough estimates. Plus, at least 2 circuits for a tank that big is a must. You will shoot yourself later for not having that extra. Also, didn't see if you were going to use dedicated circuits, but if you aren't make sure to into account the other electrical devices in the room.

HTH

Scott

[reeferbro]

I dont own a reef. I don't even own an aquarium. Although, I have been an electrician since for the past 14 years of my life. This would make me qualified to put an end to your search for an answer to your question on the GFI/ power cord predicament. Yes, you may use a 15 amp power cord. Why? Because regardless of the amount of load you will be running from these outlets( which I am sure will never be much anyway ) the GFI will sense a ground fault WAY WAY before the insulation of the wire within the cord deteriorates. Also, the short time current rating capacity of a 15 amp power cord is much more than 20 amps. Citing the National Electrical Code is way beyond the scope of this reply so just take my word for it. The GFI will trip way before the short time high current period which the cord is rated for.

[Zephrant]

Originally posted by areefer
Actually 12AWG is rated for 20Amp and 14AWG is rated for 15Amp.

Thanks AR, you are absolutely correct.

Zeph

[reeferbro]

Disregard the last reply. I just checked the list of device you got runnin' on that circuit. You are probably reaching overload conditions. Your problem is beyond the question of whether or not you need a 20 amp cord. You have to take into consideration that you are maxing out the circuit if this is being run off a 15 amp breaker your probably gonna trip it. If your coming off a 20 amp it may suffice the load being supplied to your reef, but are there any other outlets in your place being fed from this circuit?

[reeferbro]

You better check your National Electrical Code before you challenge my knowledge of Electrical installation. Article 240 of the NEC states: Where flexible cord or tinsel cord is approved for and used with a specific listed appliance or portable lamp, it shall be permitted to be supplied by a branch circuit of Article 210 in accordance with the following:
20 ampere circuits- tinsel cord or No. 18 cord or larger
30- ampere circuits- No.16 cord and larger
It then goes allthe way up to the required sizes up to 50 amp, which is of course beyond the scope of your query. So, have we all learned a valuable lesson in electricity today, class?

[reeferbro]

Hey Zephrant,
As an Engineer you should know that the allowable ampacities of wire change in accordance to the raceway ( or LACK OF BEING ENCLOSED IN A RACEWAY ). # 4 awg ALUMINUM WIRE CANNOT HANDLE 100 AMPS WHEN ENCLOSED IN RACEWAY. Though, when #4 is in free air, jumping from overhead supply lines to end user service points it is definitely rated for more. So, in the same respect power cords are given a bit more leeway to take into account the better heat transfer capabilities due to the lack of a raceway. Admit that your wrong and that you gave some bad advice to our reefkeeping friend.

[Chamkeeper]

Horn,

If you have the opportunity to run a new service for your tank, I would run 2 or 3 standard 15 amp connections. This is inexpensive and would give you some error proofing over a single high amperage circuit. As mentioned before, you can divide functions between circiuts, (heaters, pumps etc. ) so if a single breaker trips, you have some equipment working giving you some time to correct the issue.

Reeferbro,

You should know that unless you're a professional electrician, reading the NEC is pretty much like reading Tea Leaves, you can see it, but no idea of the meaning.

[reeferbro]

Chamkeeper,
If you read all my posts you would see that I suggested he should have at least one more dedicated line for his receptacle bank. But to supply each set of receptacle he only needs a 14awg cord from source receptacle to the installed receptacles in question. Duh. Yes, I am a professional. Could you show me where in the code you can defend your argument? I didn't think so!!

[reeferbro]

Chamkeeper,
If the language of the NEC comes up like tea leaves, you're probably not qualified to give someone any advice on electrical concerns.

[reeferbro]

Chamkeeper,
" If you have the opportunity to run a new service for your tank.... " SERVICE?? In the realm of electrical terminology SERVICE refers to the installation between point of supply from the power company and the main disconnect. Why are you even mentioning the word service? If you want to enter my world (electricity) first you have to learn the language. Then, we'll talk.

[scott324]

Reeferbro,

I was also an electrician and anyone that would suggest using an under rated power cord to a bank of outlets, like he is suggesting , is down right scary. Please fill in your location so I know not to recomend you to anyone.

Also, I understand you are new, but around here most people like to do things right, so following the NEC would be a good idea! You must be a contractor or exterior electrician, please look up the specs on Romex and post them here, since this is what most residential units use. Also, would you suggest running some 1/2" pipe, to constitute a raceway, for the guy to power his little bank of outlets. Talk about out of context!!

You did an awful lot of quoting there too

[reeferbro]

Chamkeeper,
You still don't understand. We are not talking about the Romex which jumps from outlet to outlet. That has to be #12awg. If the persopn who installed this receptacle bank wanted to run a cord exposed ( not in raceway! ) from the source outlet on the wall to the receptacle bank ( assuming the circuit is rated for 20 amps ) you need only a #14 awg cord. Why is it so hard to understand that wire ampacities are not always the same as for wire run in a raceway? Also, if you were an electrician , you should be able to comeback at me with a section of the NEC that would prove me otherwise! Come on man, read 240-4 of the NEC. Then you will understand. #14 is not always rated for 15 amps. On an extension cord the rating is higher and when you install it in free air it also gets a higher rating.

[horn1004]

Guys,
Thanks for the advice but let's all take a minute to calm down before this gets out of hand. I'd like to clear a couple things up while I'm at it. As I stated earlier, this tank will not be set up until I move and get settled, so I have no idea what size the breaker is because I have no idea where I'll be living when I move. Also, I got the boxes finished last night. I went to Home Depot and found this wire:

100ft for $18 isn't bad, so I got it. They did have 10g wire but the 100ft roll of that was $70, go figure. After I got done with it, I had about 15ft left off the roll. I made 4 cords about 22 ft in length, so that I can get them on seperate circuits. I had to do this because I'm probably going to be in an apartment for a while and can't go in adding circuits. Once I get into a house I can add at least one more circuit for the tank. Anyway, here are a couple pics of the almost finished product (still have to get a couple outlet plates).

[reeferbro]

Horn,
That's cool man. It definitely does'nt hurt to upsize on the wire. Just to take into consideration that cord manufacturers rate their cords at amuch lower ampere rating then their allowed by code (NEC) to take into account the worst case scenario. If many cords are put together to form a cord so long that a significant voltage drop was achieved ( for example, two 100 foot 14 awg cords put together to run a pipe threader) than there can be a problem. For future reference, only take advice from an electrician or qualified person who can cite the National Electrical Code. This way you know for sure that you are not getting an opinion as opposed to the fact. It was not my opinion that you could use a 14 awg cord, it was dictated by the article of the NEC which I cited. I dont want to offend you, but you spent way too much on your cords. This is what happens when people are confused by differing opinions from people who don't know the NEC. They end up doing much more ( overkill ) then the job calls for. With the money you wasted you could have bought some acrylic scraps to make a cool DIY calcium reactor. Nonetheless, you are a true gentleman and I appreciate the last reply you posted.

[Zephrant]

Bro- Good information on your final post. I feel you might be putting too much trust in to the NEC though. The front page of my copy says:

Purpose.
(a) Practical Safeguarding. The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity.
(b) Adequacy. This Code contains provisions that are considered necessary for safety. Compliance therewith and proper maintenance will result in an installation that is essentially free from hazard but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use.

(c) Intention. This Code is not intended as a design specification nor an instruction manual for untrained persons.

Note the sections in bold. What you have quoted above from NEC is true, but is not the only thing that needs to be considered in a good design. While an electrician tries to use the smallest gauge allowed by code (which saves significant money in large projects), a home DIYer needs to be able to pick up something easy at HD and continue with life.

Horn's selection of a 12ga extension cord is perfect for this application. Strong, flexible, and definitely large enough to carry the amps, even when tucked behind a tank with little to no air flow.

As you can see, properly quoting the NEC is great, but it is not always of sufficient help to the home hobbyist.

Thanks for your input-

Zeph