joekidwell
New member
Do I purchase the 20 amp outlets because there is a 20 amp breaker for this room?
GFIC Outlet?
- Thread starter joekidwell
- Start date
KingTriton1
New member
Yes and No. You go with the largest amp outlet that your circuit breaker can handle. If you have a 20 amp circuit breaker with 12 gauge romex (which I'd hope) then go with a 15 or 20 amp outlet. Why would you go with a 15 amp though? You never want to run more then your circuit can hold so putting a 30 amp outlet would not work in your case.
ericarenee
New member
If you have a 20 amp breaker you should get a 15 amp gfi If not the Breaker is just as likely to trip as the Gfi.. the other thing is unless you had that breaker installed for your aquarium there would surly be other outlets on that same breaker. With that said if the breaker is already pulling say 10 amps and you get a 15 amp gfi and you are pulling 4 amps on it.. then say there is a 10 amp spike on the aquarium gfi you will throw the breaker anyway...
Hope this makes it less complicated. just remember the breaker in the box that is 20 amps is likely to have a load on it other then just from that one outlet..... also a 20 amp will usually trip at about 23 or so ... but they do age ....
Hope this makes it less complicated. just remember the breaker in the box that is 20 amps is likely to have a load on it other then just from that one outlet..... also a 20 amp will usually trip at about 23 or so ... but they do age ....
joekidwell
New member
Thanks for the reply guys, I went with two 15 amp outlets.
sleepydoc
Team RC
GFIC Outlet?
Ok, guys (and gals) - time to clear some things up here.
First the ampacity of an outlet refers to the plug, not the capacity of the outlet itself. A 15A plug is the 'normal' one with 2 vertical prongs and a ground underneath. A 20 amp plug has a horizontal prong on the left and a vertical one on the right (picture). All GFCI outlets have 20A feedthrough capacity, but a 20A GFCI outlet just has the ability to handle a 20A plug.
Since none of the equipment we use for aquaria requires 20A, a 20A plug is pointless for us. Since there are two 15A outlets in a standard receptacle, you can still use all of the allowed current for the circuit, just not with one cord. If you are drawing more than 15A on one cord plugged into a 15A socket, you are drawing too much current anyway. (Any outlet strip you use will probably have at most a 15A breaker on it to prevent just this kind of overloading.)
Next, there is a difference between a circuit breaker and a GFCI breaker. The circuit breaker is there to prevent current overloading in the wiring of your house. The breaker in each circuit is sized according the the wires in that circuit. If it is a 15A breaker, the circuit was wired with 14g wire. If it's a 20A circuit it was wired with 12g wire. You can put 14 Amps though your body and electrocute yourself quite nicely and the circuit breaker won't care since you're still under the current capacity of the wiring. (Note: Do NOT try to replace a 15A circuit breaker with a 20A breaker to increase the capacity of the circuit. Doing so is asking for a fire!)
GFCIs are there to protect people from electric shocks. A 15A GFCI outlet will not trip at 15 amps. It trips when it detects current leaking out of the circuit to an alternate ground path (i.e. through your body when you're using the hair dryer in the tub.) The current threshold for this is on the order of 5 mA (0.005A)
Finally, while I'm on the subject, newer houses will have AFCI (Arc Fault Circuit Interrupt) breakers. These are designed to sense arcing or sparking, like one would see from a frayed wire, and trip before it causes a fire. This is different from over current protection and different from GFCI protection.
To answer the OPs question - you can use either, but since a 15A GFCI outlet is generally cheaper and you don't need the 20A outlet just use a 15A.
Hope this clears things up a bit.
Ok, guys (and gals) - time to clear some things up here.
First the ampacity of an outlet refers to the plug, not the capacity of the outlet itself. A 15A plug is the 'normal' one with 2 vertical prongs and a ground underneath. A 20 amp plug has a horizontal prong on the left and a vertical one on the right (picture). All GFCI outlets have 20A feedthrough capacity, but a 20A GFCI outlet just has the ability to handle a 20A plug.
Since none of the equipment we use for aquaria requires 20A, a 20A plug is pointless for us. Since there are two 15A outlets in a standard receptacle, you can still use all of the allowed current for the circuit, just not with one cord. If you are drawing more than 15A on one cord plugged into a 15A socket, you are drawing too much current anyway. (Any outlet strip you use will probably have at most a 15A breaker on it to prevent just this kind of overloading.)
Next, there is a difference between a circuit breaker and a GFCI breaker. The circuit breaker is there to prevent current overloading in the wiring of your house. The breaker in each circuit is sized according the the wires in that circuit. If it is a 15A breaker, the circuit was wired with 14g wire. If it's a 20A circuit it was wired with 12g wire. You can put 14 Amps though your body and electrocute yourself quite nicely and the circuit breaker won't care since you're still under the current capacity of the wiring. (Note: Do NOT try to replace a 15A circuit breaker with a 20A breaker to increase the capacity of the circuit. Doing so is asking for a fire!)
GFCIs are there to protect people from electric shocks. A 15A GFCI outlet will not trip at 15 amps. It trips when it detects current leaking out of the circuit to an alternate ground path (i.e. through your body when you're using the hair dryer in the tub.) The current threshold for this is on the order of 5 mA (0.005A)
Finally, while I'm on the subject, newer houses will have AFCI (Arc Fault Circuit Interrupt) breakers. These are designed to sense arcing or sparking, like one would see from a frayed wire, and trip before it causes a fire. This is different from over current protection and different from GFCI protection.
To answer the OPs question - you can use either, but since a 15A GFCI outlet is generally cheaper and you don't need the 20A outlet just use a 15A.
Hope this clears things up a bit.
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Sorry, the third post should be disregarded. A gfci circuit in your outlet and the breaker rating are two very different things.
Johnseye
Reef Addict
Correct me if I'm wrong, but you are still able to draw up to 20 amps on a 20A circuit while you can only draw up to 15 on a 15A. This may seem obvious, but it's not just about the type of plug, it's also about the total draw of amperage. I'm not an electrician, so please correct me if I'm mistaken.
sleepydoc
Team RC
Not sure what your question is - if you have a 20 A circuit with a standard 15A plug, the breaker won't trip until 20A (nominally,) but assuming you have appropriate wire on the plug, you should not be drawing that much current from a single cord plugged into the outlet. The wiring in the wall will be fine, but the wire plugged into the outlet will not be fine.
If you have only one 2-outlet receptacle on the 20 A circuit, you could theoretically have up to 15A flowing through each outlet with a maximum of 20A total.
ericarenee
New member
You are Correct... IF you have a 15 amp gfi on a 20 amp circuit and there is a short. it will TRIP THE GFI NOT THE BREAKER.... unless the breaker is weak. OF Course some of the newer breakers as explained above with ark falt could trip first.
the thing is why did the short/ over current occur was it passed thru ground by a faulty device or just shorted out....A GCI WILL TRIP On either instance..
ericarenee
New member
this is true but the cfgi is needed because if a device 3 plug shorts out even if its not reaching the Trip level of the breaker on it. The Gfi will sense that voltage in the ground and TRIP.....
This is actually every easy to cause as pumps and equipment age..
Every time i have had one to trip and i go looking for the issue its been a wave pump heater or similar under water equip with a short usually worn out cord. with out the gfi you would have fried fish..
Johnseye
Reef Addict
I was trying to say that with a 20 amp circuit and a 20 amp outlet you get 20 amps worth of draw, thus you're able to power more equipment than on a 15 amp circuit, regardless of whether aquarium equipment has 20 amp plugs or not.
Here's some info I pulled from elsewhere...
The first thing to know is that circuits should only be loaded at 80% of the total circuit load. To help you understand the concept, if you have a 15-amp circuit, the safe operating amperage would be no greater than 12 amps. The total wattage would be 1,800 watts, meaning the safe wattage usage would be 1,440 watts.
If you have a 20-amp circuit, the safe operating amperage would be no greater than 16 amps. The total wattage would be 2,400 watts, meaning the safe wattage usage would be 1,920 watts.
ericarenee
New member
this is why you would put a 15 amp gfc on a 20 amp breaker. and remember breakers also get weak over time and start tripping at a lower amp if they are run at close to max too long.
ericarenee
New member
So you are saying a 15 amp gfi will NOT TRIP Unless there is a GROUND Fault .. This is not true... it will trip at 15 amp. ususally less OR IF A Ground fault occurs this would only be on equipment with 3 wires. Rare on older aquarium equipment..This brings me to the reason to have a Grounding probe in any body of water with a heater. most are have no ground.
KingTriton1
New member
Since you only want to draw a max of 80% from your outlet I would have chosen a 20A outlet personally. However, Im more of a do it yourselfer with a few zaps here and there experience 
ericarenee
New member
Since you only want to draw a max of 80% from your outlet I would have chosen a 20A outlet personally. However, Im more of a do it yourselfer with a few zaps here and there experience
But do you want the GFI to trip or your circuit breaker. Likely both..
I think some above are getting into to much of the technical reasoning.
The IDEA is to trip the gfi next to your tank not the whole circuit..as that circuit probably has other rooms and Outlets on the breaker..
This thread went away from the reason behind the original question....
oh here is my last construction project i did start to finish. it was only 4.3 million dollars.
KingTriton1
New member
Need a contract bonding agent by any chance?
What exactly would cause it to trip?
What exactly would cause it to trip?
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ericarenee
New member
Need a contract bonding agent by any chance?
I actually now work in Residential . We Renovate historic homes. i got so sick of traveling for a living..
What exactly would cause it to trip?
Well It would trip if there was a short.. something behind it pulled more then its trip amp level..... or a ground fault occurs...
Anyway i will shup on this now.. i was just making my case that a gfi is also a breaker. not just a ground fault protector...
sleepydoc
Team RC
You can pull 20A through a 15A receptacle, just not though a single plug (assuming the plug is properly wired.) You are correct that you do not want to run a circuit at full capacity. I left that part out above to make things simpler. Taking it further, the rate at which a breaker trips is dependent on the current. It will trip faster at a higher current than a lower one, so it's not quite as black and white as '20A' makes it seem.
Yes - this is precisely the value and purpose of a GFCI outlet for your tank; so you don't get a nasty surprise one day when the cord for your pump or heater develops a crack and you put your hand in the water!
Not to be contradictory, but this is an important point - GFCIs will NOT trip on current overload, assuming the current is flowing where it should. A short between the hot and neutral prongs in a GFCI outlet will trip the circuit breaker but not the GFCI. A short between the hot wire and ground will trip the GFCI before it trips the circuit breaker.
All of the sources & specifications I've seen state that GFCIs do not provide over current protection; If you have sources/specs to the contrary, please post them.
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