lets get real. how big is your power strip?

[Kodski]

This may be a stupid question, but how much equipment can you technically have for a 15amp, 20amp, and 30amp, circuit before its considered too much? Is it measured in watts or something else? I'm about to run a new circuit for my new tank and would like to know what size breaker/wire I need to add.


I also bought a very old (1900 build date with true 2"x4" balloon framing) house with knob and tube wiring. The only thing was that we didn't really know it had knob and tube wiring. The previous owners had the breaker box updated so from our inspection everything looked updated minus a few two prong outlets. Turned out they literally just spliced into the old wiring with the new wiring.

Luckily we were going to redo all the floors in the house, so I was able to replace all the old wiring by either pulling up flooring or running a fish tape through the walls. All in all, all those long and very sweaty days spent in the attic just means that I can sleep a little safer at night. Perk to that, is I now know 100% how the house is wired and can add stuff very easily. lol

 

[Beau_B]

Watts, yes.

Watts = Amps x Volts

So… if your running 300w heater, 200w lighting, 200w pumps… that’s 700w/120v = 5.83 amps on your circuit. Plus all the other stuff that may be on that circuit (you would know what else having wired it!). Obviously plenty of room on a 15A.

Aim to stay under 80% of the breaker rating. Or about 1500w. It’s not a coincidence that most widely available space heaters and AC units max at 1500W. Do not change your breaker to higher rating… duh.

edit to add: 1500w for a 15A circuit, which remains the most common in living/bedrooms. Depending on the age and other factors it may be 20A but if in question, assume 15.

 

[laverda]

You would be better off with two 15 or 20 amp circuits than one 30 amp.
There are plenty of calculators available online. You can use either watts or amps to calculate the load. Watts (W) is equal to the current I in @xx n 9pjup
amps (A), times the voltage V.
So 5 Amps at 120 Volts equals 600 Watts.

 

[Kodski]

Great! So if I plan to add a single 20amp breaker just for the tank it sounds like that should be enough. But I’ll calculate with all my equipment and make sure it’s under 80% of the 20amps. If it’s too close with the equipment I can think of I’ll add two 15amp circuits instead. Thanks @Beau_B and @laverda!