840w LED lights 15 amp or 20 amp breaker?
- Thread starter Lilmink
- Start date
bk78
Well-Known Member
I mean you still need fans dehumidifier, AC etc?
Yeah definitely need more breakers installed.
Drop That Sound
Well-Known Member
I've got tandem 15 and 20 amp 1 pole dual circuit breakers like this for my grow;
2 breakers in one slot, to save a lot of space, which is needed with smaller sub panels mostly..
You could think of a 2-15 as a 30 amp 120v breaker in a way.. like, it's still only 2 x 15's, but without taking up 2 whole slots though.
Then I just run 1 circuit to each separate light\area. I know I can power a fan, complete hydro system w/ air/water pumps, 10 amps worth of light, all off of one of the 2 circuits from the dual breaker.
I'm not having 2 lights fire up off of 1 breaker that way either, as some lights\gear need lots of starting amperage to fire up.
P.S. (as i'm sure most of you know) 20 amp takes a lower gauge thicker wire, so don't go swapping any 15s out for 20s ,without first replacing everything else down the line too.
2 breakers in one slot, to save a lot of space, which is needed with smaller sub panels mostly..
You could think of a 2-15 as a 30 amp 120v breaker in a way.. like, it's still only 2 x 15's, but without taking up 2 whole slots though.
Then I just run 1 circuit to each separate light\area. I know I can power a fan, complete hydro system w/ air/water pumps, 10 amps worth of light, all off of one of the 2 circuits from the dual breaker.
I'm not having 2 lights fire up off of 1 breaker that way either, as some lights\gear need lots of starting amperage to fire up.
P.S. (as i'm sure most of you know) 20 amp takes a lower gauge thicker wire, so don't go swapping any 15s out for 20s ,without first replacing everything else down the line too.
Do these dual circuit breakers handle double the amount of amps ? 20 amp dual will handle 40 amps?
Drop That Sound
Well-Known Member
No they are split from each other. It's just 2 breakers in one.
I was just answering your question about having a 30 amp breaker that is 120v. It kind of is in a way but not really.
I was just answering your question about having a 30 amp breaker that is 120v. It kind of is in a way but not really.
Drop That Sound
Well-Known Member
But, If your lights run on 220-240v, you could use lower amperage 2 pole breaker, and run a single circuit in there to hook them all up too.
Lenin1917
Well-Known Member
Yeah but, I’m neither an electrician or a homeowner so I’m limited by my unwillingness to put equity into my landlords property and a lack of readily accessible information on old knob and tube grids
Lenin1917
Well-Known Member
That’s the fuse my ac and dehumidifiers were on till it blew last night when the power went out and they all came back on at the same time 
(didn’t realize they were on the same circuit, should’ve double checked) now I’m without ac till tomorrow afternoon. But my temps are good enough that I might not run the ac that mf draws 1300w and if my flower tent can stay below 90f without it then I’m gonna save that money.
(didn’t realize they were on the same circuit, should’ve double checked) now I’m without ac till tomorrow afternoon. But my temps are good enough that I might not run the ac that mf draws 1300w and if my flower tent can stay below 90f without it then I’m gonna save that money.
Drop That Sound
Well-Known Member
Dang, do they all have the usual 5 minute startup delay?
MidnightSun72
Well-Known Member
4x840W = 3360W
@240V 3360/250=14amps
@120V 3360/120= 28amps
so ya you'll want to go 20amp at 240V because LEDs have a big inrush current when drivers first start up. And you don't wanna be checking breakers all the time.
edit: or you can go 30amp on 120V but have fun wiring those receptacle. The wire will be huge for the 120 receptacles. You could also run two lines at 15amps (left side and right side or front and back of room depending what's easier and shorter length to wire from the panel.
@240V 3360/250=14amps
@120V 3360/120= 28amps
so ya you'll want to go 20amp at 240V because LEDs have a big inrush current when drivers first start up. And you don't wanna be checking breakers all the time.
edit: or you can go 30amp on 120V but have fun wiring those receptacle. The wire will be huge for the 120 receptacles. You could also run two lines at 15amps (left side and right side or front and back of room depending what's easier and shorter length to wire from the panel.
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Lenin1917
Well-Known Member
Not sure, judging by their(the dehumidifiers) coming back on immediately when I plugged them into extension cords on different circuits I’m gonna guess no. The ac I can’t plug into an extension cord because it’s just to much power for that. I have a smaller unit I need to pick up from my mom now that she’s got central air, but that was gonna be for the dry room. Swtg growing weed feels like a money pit sometimes. Even were I to max out my capacity to something like 10lbs e10w I’d still be kinda broke
xox
Well-Known Member
i would just get one of these https://hydrobuilder.com/titan-controls-helios-11-4-light-240v-controller-w-trigger-cord.html i have one installed at my place its nice and simple. if your already thinking about putting in multiple 20 amp circuits just be done with it and put one 30amp 240v circuit for the lights its probably easier. you'll also only need one timer as it has a trigger cord. on a side note @Lenin1917 i personally wouldnt want to be living in a building that has knob and tube wiring its a pretty serious fire risk even when just using regular appliances and whatnot in a house. however just because your on a fuse panel doesn't necessarily mean you have knob and tube you wont know until you open a wall and see the knob and tube.
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What this guy said. I need to fire up 2 more ac and can't because I only have 20amps. The ac pulls 15 each alone. I'm gonna put in 240v dedicated lines
Lights should not pull that many amps. Air conditioners dehumidifiers well pumps. Those are your amp eaters
ComfortCreator
Well-Known Member
The wiring in your setup determines the max breaker amps you can install. More amps is better all things considered.
Breakers can trip and be reset many times with no loss. They also can degrade over time or from overload. They are not particularly expensive but installing breakers is a job for an electrician (or someone with experience).
Your box only handles so many amps, that is another limiting factor.
I would guess 2 - 20s can be done with existing wiring.
Breakers can trip and be reset many times with no loss. They also can degrade over time or from overload. They are not particularly expensive but installing breakers is a job for an electrician (or someone with experience).
Your box only handles so many amps, that is another limiting factor.
I would guess 2 - 20s can be done with existing wiring.
but the rent is cheap, gotta love that it’s the landlords who write our housing codes.I had to rewire my entire home because it had antique breakers and glass fuses. It's a miracle this house is standing. We got inside the walls and it gave me chills. I put in modern out side meter breaker box. And breaker box indoors. No we're running 2 dedicated lines just for the grow. 220v and 120v dedicated lines. Gear doesn't have to work as hard if it's 220 meaning longer lifespan.
Oh shit I just gutted my entire home because it had those fuses