Electrical Help! Fire Hazard! Expert Advice needed!

[TwinTurboGuy]

Okay here's the deal. I rented half of a duplex with my other housemates on the other side. Problem is that there is a main breaker panel, but each of us get an individual subpanel. So tapping into the main breaker panel is not an option as it would raise my neighbor's curiosity and cause some suspicion.

Mine and my neighbors panel is rated at 50 amps, but what I want to do is run 4kw lights and fans on a 50amp light timer along with other things such as daily living appliances. My subpanel initially had 2 15amps breakers and a 30 amp breaker.

I'm suspecting that the 50 amp subpanel is using a high voltage feed from the main panel. Would it still be safe to run the 50amp timer running 240v outlets and keep the other two 15 amp breakers in there feeding my other appliances?

I don't want to cause a fire and I only know basic electricity. Help!

 

[StephenMcTowlie]

A 1000 watt light running on a 240 volt branch circuit will draw about 4.15 amps , so theoretically, yes, you could run all four lights from that 30 amp service. (Ohm's law: power in Watts equals Voltage * Amperage. 1000 Watts / 240 Volts = 4.166 Amps. On a 120 Volt branch, that same light would draw 8.3 amps) But that circuit is probably already being tapped to run a big appliance, like a hot water heater or a fridge, a/c, etc. Find out what's being powered by it now (flip the breaker and see) and learn to live without it if you need all that light. You need to make sure that only the lights are on that circuit, and that your ballasts are wired for 240 volts. Don't run your fans off the 240 volt service, they're almost certainly wired for 120V.

 

[madpenguin]

Okay here's the deal. I rented half of a duplex with my other housemates on the other side. Problem is that there is a main breaker panel, but each of us get an individual subpanel. So tapping into the main breaker panel is not an option as it would raise my neighbor's curiosity and cause some suspicion.

? That's not possible. Each sub panel needs to be separately metered. Where is this "main panel"? Is it actually a disconnect on the outside of the house? Are there 2 meters as well?

Mine and my neighbors panel is rated at 50 amps, but what I want to do is run 4kw lights and fans on a 50amp light timer along with other things such as daily living appliances. My subpanel initially had 2 15amps breakers and a 30 amp breaker.

What do the markings say on the cable that feeds your sub panel? What size breaker is in the "main panel" that feeds your sub panel? 50 amp?

I'm suspecting that the 50 amp subpanel is using a high voltage feed from the main panel. Would it still be safe to run the 50amp timer running 240v outlets and keep the other two 15 amp breakers in there feeding my other appliances?

If you already have a 50A timer, it will work. A tad overkill for your setup tho. Is your furnace gas or electric? Same question with a stove. Do you have a washer/dryer?

 

[TwinTurboGuy]

Sorry guys here is a little more detail.

There is a main breaker panel run on one meter rated at 200amps.

The main panel has alot of 15 and 20amp breakers on them already powering the water heater, washer, dryer, etc. There is also two 50amp breakers each wired to a subpanel on each end of the duplex powering just basic lighting. I actually do the financing and accounting for the landlord as my housemates already pay fixed amount of rent for utilities, so security isn't much of an issue for just using one meter.

On my panel, I'm only using 15 amps for just simple lighting and a computer. Then there is space for 2 more breakers. My problem is, if that subpanel is rated at 50amps, can I use a 50amp breaker on that panel to power my 50amp timer to juice the lights? My lights will be running on 240v and of course my fans will be on 120v.

 

[madpenguin]

Sorry guys here is a little more detail.

There is a main breaker panel run on one meter rated at 200amps.

The main panel has alot of 15 and 20amp breakers on them already powering the water heater, washer, dryer, etc. There is also two 50amp breakers each wired to a subpanel on each end of the duplex powering just basic lighting. I actually do the financing and accounting for the landlord as my housemates already pay fixed amount of rent for utilities, so security isn't much of an issue for just using one meter.

On my panel, I'm only using 15 amps for just simple lighting and a computer. Then there is space for 2 more breakers. My problem is, if that subpanel is rated at 50amps, can I use a 50amp breaker on that panel to power my 50amp timer to juice the lights? My lights will be running on 240v and of course my fans will be on 120v.

Yes, you can install a 50A breaker in your sub panel. You could install a 200A breaker in your sub. It's the 50A double pole back in the main panel that will kick if you draw too much power.

So.... The landlord directly pays all utilities then? I realize you said the 2 tenants (you and your next door neighbor) pay a set amount, but what's going to happen when the electric bill jumps by $200 a month? Kinda hard to hide that if your not paying your own bill.

If a residence doesn't have it's own meter then I wouldn't even consider growing there. If your still going to do it, I'd look at the cable sheathing that feeds your sub and make sure the ampacity of the wire is sized correctly for the 50A back in the main. I'd also make sure the ampacity rating of the actual sub can handle it as well.

 

[TwinTurboGuy]

Thanks! Just the response I needed!

I figured that even if I draw 5k watts, I would still have some slack to play with. Even at 240v and 50amps, I can probably run 12k watts all together (which of course I'm not going to do). And it is already assuming that wire from the main to the sub is rated at 240v (which I doubt and its probably rated higher).

Correct me if I'm wrong, but thanks again!

 

[sparkjumper]

Yea bro I'd say there's something wrong with doing a 5K grow in a duplex where the landlord pays the total for both units.You really should rethink this

 

[Hydro-Soil]

Yea bro I'd say there's something wrong with doing a 5K grow in a duplex where the landlord pays the total for both units.You really should rethink this

The landlord is NOT the power company and knows pretty damn well how much power his tenants usually use. A spike like that will bring up questions for sure.

 

[madpenguin]

And it is already assuming that wire from the main to the sub is rated at 240v (which I doubt and its probably rated higher).

Correct me if I'm wrong, but thanks again!

Your feeder wire to the sub should be rated at 600v but that doesn't really matter. You'll only have about 125v on the black and 125v on the red for a total of 250v (plus or minus 10) between both hot lugs in your sub panel. It's your amps/watts that you need to keep an eye on.

Again.... If the electric bill isn't in your name, I wouldn't do it. You would be asking for trouble unless your landlord knew what you were doing and was ok with it.