-
Welcome back Guest! Did you know you can mentor other members here at H-M? If not, please check out our Relaunch of Hobby Machinist Mentoring Program!
Weird question, need help
- Thread starter Mike8623
- Start date
- Joined
- Jan 2, 2019
- Messages
- 7,177
If you run 240v with a neutral AND a ground, providing you are running the proper breaker and wire sizing, you could run 4 conductors to your hut and install a sub-panel that would provide more reliable power. You could have two 120v circuits and possibly run your lights and a small heater, but nothing big enough to get you through a Montana winter. Propane or wood heat will work best for this kind of situation.
For a 350' run with a 20 amp 240v circuit you should be able to use 12awg wire. That would be 4 conductors L1, L2, Neutral and ground. Home depot has 500' spools of 12awg for $105, you'll need a 20 amp 240v dual breaker, and some kind of sub-panel with breakers and outlets. Could probably DIY for less than $500 and have something close to what code would require.
It's not that tough, but if you're not familiar with electrical work you should definitely find someone who is to lend a hand. It looks like you have plenty big enough conduit running there but best practice would be to bury the conduit rather than leaving it on the ground.
I deal with this kind of stuff at work and home so I'm comfortable with it but please, DO NOT take any of this as definitive advice telling you how to run electricity on your property.
Honestly, it's not that tough but only you can determine if it's worthwhile doing it right. Your current setup will eventually fail, but if it's properly grounded and protected by a circuit breaker you'll probably be safe enough leaving it as is. Just don't try to run your heater off it, that's asking for trouble.
John
Hi @Mike8623
Folks here explained things pretty well. You said the lights dim, not the TV. Does it dim also? Which part of dimming bothers you the most? Maybe this is something you just want to put up with, but read on.....
You are dealing with a power limitation issue, which can manifest its self as an observable voltage issue at the loads. The power delivered is both to the heaters, tv, lights, etc which we normally call the electrical load but also to the extension cord. The total power delivered from the outlet is P = I *V where I is the current, and V is the voltage. However the extension cord also consumes part of the power during delivering the current to the load(s). Basically the extension cord is a long resistor, R, which heats up a bit when current flows through it. This is normal, but must be designed for. As the cord is made longer, or the wire size is made smaller, the fraction of the power going to heat the cord gets larger. That is its resistance is larger. That means of course that less of the power goes to the load while more of it is going to the cord. Since all of the load current, I, travels along the cord, as well as, through the load, the fraction of the voltage being delivered to the load is less. Hence, dimming can appear as the larger load appliance changes (heater turns on and off.)
Putting safety and electrical code aside for the moment, your dimming issue may only be an inconvenience and not harmful.
I assume the heaters are just radiant resistive heaters, which if this is the case a low voltage to them will not harm them. On the other hand if there are fan motors involved a low voltage may harm them and cause them to burn out early. ( If the power company has too many users and big equipment gets switched on the voltage to your house may drop. In which case this is called a "brown out." A severe and continued brown out will kill things like motors and some electronics. i.e AC compressor motors, refrigerators, computers, displays, etc., However, most modern electronics can tolerate small or limited brown outs.)
While the extension cord in a pvc pipe is not normal, since you really only load it when it is cold outside (electrical heaters), the cord probably does not get very hot and so does not represent a fire threat. However, if you also use this in the summer, with Air conditioner motors then this is a more serious issue and you may want to/should consider getting more power service installed to the shed.....
Folks here explained things pretty well. You said the lights dim, not the TV. Does it dim also? Which part of dimming bothers you the most? Maybe this is something you just want to put up with, but read on.....
You are dealing with a power limitation issue, which can manifest its self as an observable voltage issue at the loads. The power delivered is both to the heaters, tv, lights, etc which we normally call the electrical load but also to the extension cord. The total power delivered from the outlet is P = I *V where I is the current, and V is the voltage. However the extension cord also consumes part of the power during delivering the current to the load(s). Basically the extension cord is a long resistor, R, which heats up a bit when current flows through it. This is normal, but must be designed for. As the cord is made longer, or the wire size is made smaller, the fraction of the power going to heat the cord gets larger. That is its resistance is larger. That means of course that less of the power goes to the load while more of it is going to the cord. Since all of the load current, I, travels along the cord, as well as, through the load, the fraction of the voltage being delivered to the load is less. Hence, dimming can appear as the larger load appliance changes (heater turns on and off.)
Putting safety and electrical code aside for the moment, your dimming issue may only be an inconvenience and not harmful.
I assume the heaters are just radiant resistive heaters, which if this is the case a low voltage to them will not harm them. On the other hand if there are fan motors involved a low voltage may harm them and cause them to burn out early. ( If the power company has too many users and big equipment gets switched on the voltage to your house may drop. In which case this is called a "brown out." A severe and continued brown out will kill things like motors and some electronics. i.e AC compressor motors, refrigerators, computers, displays, etc., However, most modern electronics can tolerate small or limited brown outs.)
While the extension cord in a pvc pipe is not normal, since you really only load it when it is cold outside (electrical heaters), the cord probably does not get very hot and so does not represent a fire threat. However, if you also use this in the summer, with Air conditioner motors then this is a more serious issue and you may want to/should consider getting more power service installed to the shed.....
Thanks folks for all the help and info. I'll have to save for this. The electrician wanted 6000.00 to do this. I don't have 6,000.00 or close to that. I'm 74 and on social security. My check went up 26 dollars a month for 2024. I may very well not make it to the point where I have 6 grand.....I'll just move along and be grateful for the life and what GOD gave me. I am so thankful to be where I am at.
Again thanks to all that responded
Again thanks to all that responded
- Joined
- Nov 25, 2015
- Messages
- 9,840
I didn't have fiber until recently. How the heck did you get it so much sooner.
No idea......the phone company just put it in.....my wife takes care of all that stuff. It is a long steep run from the back of my place down to where they brought the power up.....I do know I had fiber before most folks in our little town. They had to go downhill to put it in to steep to come up the hill and it was a long ways.
- Joined
- Feb 1, 2015
- Messages
- 10,024
If you are running 240 out to tour man cave, run your two heaters, one on either leg to balance the load. With a balanced load, there is no current through the neutral. #10 AWG wire has a resistance of 1 ohm per thousand feet. You are running 500 ft; 250 out and 250 back and would have a total line resistance of .5 ohms. For a 10 amp heater draw, that would be a 5 volt drop and the power consumed by the extension would be 50 watts. If you run both heaters on the same leg, it would be a 20 amp draw on that leg plus 20 amps through the neutral. The line voltage drop would now be 10 volts and the power consumed by the extension would now be 200 watts.
However, if you run the heaters, one on each leg. L:1 has a current draw of 10 amps and L2 has the same. The resistance of each leg is 250 x .001 or .25 ohms. and each leg has a voltage drop of 2.5 volts or half of what running a single heater would see. The power consumption of each leg will be 25 watts for a total of 50 watts. It seems like magic but it really isn't, just some basic physics.
Assuming a 10 amp draw on each leg, you are only generating .2 watts/ft. The heater tapes use for keeping pipes from freezing generate around 5 watts/ft/ I wouldn't worry about overheating the wire in the conduit.
BTW. #12 AWG has a resistance of about 1.6 ohms/1000 ft. Wire resistance doubles for every increase of three AWG wire sizes. This means that if the 100 ft. run has #12 AWG wire, it would have a resistance of .16 ohms for each leg or .32 ohms for the round trip or 60% of what the extension is.
However, if you run the heaters, one on each leg. L:1 has a current draw of 10 amps and L2 has the same. The resistance of each leg is 250 x .001 or .25 ohms. and each leg has a voltage drop of 2.5 volts or half of what running a single heater would see. The power consumption of each leg will be 25 watts for a total of 50 watts. It seems like magic but it really isn't, just some basic physics.
Assuming a 10 amp draw on each leg, you are only generating .2 watts/ft. The heater tapes use for keeping pipes from freezing generate around 5 watts/ft/ I wouldn't worry about overheating the wire in the conduit.
BTW. #12 AWG has a resistance of about 1.6 ohms/1000 ft. Wire resistance doubles for every increase of three AWG wire sizes. This means that if the 100 ft. run has #12 AWG wire, it would have a resistance of .16 ohms for each leg or .32 ohms for the round trip or 60% of what the extension is.
Thanks to all.
I've been here 25+ years and have never had a problem with any of the animals. I do carry a gun with me anywhere I go and have had a few times when I was a little worried but I have two very large dogs that keep the critters away from the house although it does have a drawback....they also run off all the deer, elk and moose. I believe in live and let live....they leave me alone I leave them alone and as long as I can buy some hamburger at the store I have no need to harvest any of them.
I've been here 25+ years and have never had a problem with any of the animals. I do carry a gun with me anywhere I go and have had a few times when I was a little worried but I have two very large dogs that keep the critters away from the house although it does have a drawback....they also run off all the deer, elk and moose. I believe in live and let live....they leave me alone I leave them alone and as long as I can buy some hamburger at the store I have no need to harvest any of them.
