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03-08-2009, 03:12 AM   #16
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well im completely lost..Just gonna run the A.C. on its own 20 amp breaker-ill have to unplug the heater but oh well. As for the ballast for my fishtank bulb, the guy at the store sold me an actual power cord thats rated for 240 volts, saying ill be able to cut my amps in half..im not concerned with wattage, I just dont want to overload the breaker. How can it use the same wattage but half the amps? Also, the three pronged plug is completely different from my outlets. How would I even use this cord?

 03-08-2009, 07:16 AM #17 Member   Join Date: Jan 2009 Location: Boston, MA Posts: 241 Rewards Points: 150 I have never seen a 240 volts extension cord, but then again as stated previously I am not too familiar with 240 volts. If it is 240 volts you are going to need to put in new wiring with a new outlet for the extension cord. You might as well run a new 240 volt circuit to near your fishtank and get rid of the extension cord. Extension cords are not designed to be used on a permanent basis from what I understand. __________________ One Pound of Knowledge Requires Ten Pounds of Common Sense In Order To Be Useful
 03-08-2009, 12:30 PM #18 Idiot Emeritus   Join Date: Mar 2008 Location: Fernley, Nevada (near Reno) Posts: 1,849 Rewards Points: 1,492 Here's the lowdown on the watts vs. volts vs. amps thing. In order to keep it as simple as possible, I'll ignore the effects of power factor, reactance, inductance, phase angle, voltage drop, and a myriad of other technical stuff. Watts = Power. This is what actually does the work. It's also what you pay for. Amps; This is how fast the electrical current flows down a wire. Current (amps) flowing through a wire causes heat. This is why we have circuit breakers and fuses. Too many amps = too much heat = melted insulation, fires, explosions, etc. Volts; This is how hard the electricity is able to be pushed through the wire. Sort of like the amount of pressure in a pipe. Higher pressure, more water out the end; higher voltage, more power at the end. Volts X Amps = Watts. Suppose we have two electric heaters, each one is 3000 watts. Suppose one of them is designed for 120 volts, the other is 240 volts. Suppose we connect each of them to the proper voltage. Each heater is producing 3000 watts of heat. Both the same. Using the above formula, the 120 volt heater needs 25 amps. (3000 divide by 120 = 25). The 240 volt one needs 12.5 amps. (3000 divide by 240 = 12.5). Remember, wire size is based on amps. As you can see, with the higher voltage, the amps is lower, and smaller wire can be used to power the same amount of load. This is the main advantage to higher voltage. It's very important to note, every electrical device must be operated at (or near) its design voltage. If not, really bad things will happen. If a 120 volt device is powered by a 240 volt circuit, it'll be destroyed in a second or so. If a 240 volt device is powered by a 120 volt circuit, it simply won't work. Rob

 03-08-2009, 12:36 PM #19 Newbie   Join Date: Mar 2009 Posts: 13 Rewards Points: 10 Its not exactly a 240v extension cord-heres a pic. It obviously wont plug in to my wall outlet but is there an adapter plug that will accomodate a 240v plug and work with a 120v wall outlet, while still utilizing 240v? If not, Ill just return it, just not sure why the guy sold it to me in the first place if its impossible to use.By the way thanks to the guys who answered my initial questions. Attached Thumbnails
 03-08-2009, 12:41 PM #20 Newbie   Join Date: Mar 2009 Posts: 13 Rewards Points: 10 rob, so basically according to your last paragraph, this 240v power cord I have is useless?
03-08-2009, 12:55 PM   #21
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Quote:
 Originally Posted by Electricnewb rob, so basically according to your last paragraph, this 240v power cord I have is useless?
If it will not put into your receptcale, then it can not be used.
There is no way you can put an adapotor on this cord, plug it in and get 240 volts.

Can you take a pic of both ends?
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Last edited by jbfan; 03-08-2009 at 01:38 PM. Reason: spelling

 03-08-2009, 01:34 PM #22 Newbie   Join Date: Mar 2009 Posts: 13 Rewards Points: 10 heres another pic Attached Thumbnails
 03-08-2009, 02:44 PM #23 Idiot Emeritus   Join Date: Mar 2008 Location: Fernley, Nevada (near Reno) Posts: 1,849 Rewards Points: 1,492 The male plug on that cord is indeed 240 volts. The NEMA designation for it is 6-15. 15 amps, 240 volts. There isn't any way you can get 240 volts from a standard household receptacle. Look carefully at the ballast for the fish tank. It will have a voltage rating on it somewhere. If it's 120, just get a power cord with a regular plug on it, and it'll work. If it's 240, you'll need to run a separate 240 volt circuit for it. If it's 240, and less than 12 amps, 14/2 and a 2 pole 15 amp breaker will work. If it's between 12 and 16 amps, 12/2 and a 20 amp 2 pole breaker will be needed. If it's between 16 and 24 amps, it'll need 10/2 and a 30 amp 2 pole breaker. If the ballast is 240 volts and less than 1 amp, a step-up transformer will likely be less money and a lot less effort than a new circuit. Rob
 03-08-2009, 03:14 PM #24 Member   Join Date: Jan 2009 Location: Boston, MA Posts: 241 Rewards Points: 150 Micromind, Thanks for the explanation. Very informative and very well explained. Thanks for your time. __________________ One Pound of Knowledge Requires Ten Pounds of Common Sense In Order To Be Useful
 03-08-2009, 11:04 PM #25 Newbie   Join Date: Mar 2009 Posts: 13 Rewards Points: 10 ill go back and get a regular cord.thanks for your time.
 03-08-2009, 11:06 PM #26 Newbie   Join Date: Mar 2009 Posts: 13 Rewards Points: 10 any idea why they even offer the 240v plugs if theres no way to use them in a standard house recepticle?
03-09-2009, 07:31 AM   #27
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Quote:
 Originally Posted by Electricnewb any idea why they even offer the 240v plugs if theres no way to use them in a standard house recepticle?

Some devices do require 240v. When you do need 240v, you usually install a dedicated circuit (there may be some exceptions) with a 240v outlet.

They are different to prevent you from plugging a 240v device into a 120v outlet or a 120v device into a 240v outlet.

By the way, plugging a 120v device into a 240v device may cause it to smoke...

 03-09-2009, 11:15 AM #28 Newbie   Join Date: Mar 2009 Posts: 13 Rewards Points: 10 copy that. thanks alot-appreciate it
03-09-2009, 07:11 PM   #29
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Quote:
 Originally Posted by micromind The male plug on that cord is indeed 240 volts. The NEMA designation for it is 6-15. 15 amps, 240 volts. There isn't any way you can get 240 volts from a standard household receptacle. Look carefully at the ballast for the fish tank. It will have a voltage rating on it somewhere. If it's 120, just get a power cord with a regular plug on it, and it'll work. If it's 240, you'll need to run a separate 240 volt circuit for it. If it's 240, and less than 12 amps, 14/2 and a 2 pole 15 amp breaker will work. If it's between 12 and 16 amps, 12/2 and a 20 amp 2 pole breaker will be needed. If it's between 16 and 24 amps, it'll need 10/2 and a 30 amp 2 pole breaker. If the ballast is 240 volts and less than 1 amp, a step-up transformer will likely be less money and a lot less effort than a new circuit. Rob
Rob,

I have a deep well pump most likely a franklin 1HP Says on control box. The pump stopped working I checked the power to control box which has both run and start caps, potential relay and a rest button three terminal. The amp draw on yel wire is 10A, check the res of each yel blk and red all seem within range 10, 2 12

I tried to check the caps out of circuit but nothing no needle movement goes to 0 but but not back The thermal reset show 0 in all button positions

no indicated shorts to ground wire from motor. Strange voltage readings across the yel to red of over 300v, but only 240 at teh contactor and l1 and l2 inputs.

Any Ideas?

Howard

03-09-2009, 07:13 PM   #30
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Rob,

I have a deep well pump most likely a franklin 1HP Says on control box. The pump stopped working I checked the power to control box which has both run and start caps, potential relay and a rest button three terminal. The amp draw on yel wire is 10A, check the res of each yel blk and red all seem within range 10, 2 12

I tried to check the caps out of circuit but nothing no needle movement goes to 0 but but not back The thermal reset show 0 in all button positions

no indicated shorts to ground wire from motor. Strange voltage readings across the yel to red of over 300v, but only 240 at teh contactor and l1 and l2 inputs.

Any Ideas?

Howard

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