Amps per hour on an AC Motor

[Brakes]

I was wondering if anyone can answer this. My brake lathe motor has a single phase motor. It reads 115voltage and pulls 11.4 continuous amps. Now with that being said , how many amps is that an hour or is that the hour amperage. Im new to this and would like to go completely solar. So im trying to find out how many batteries I would need at what amperage, what kind of batteries, how many solar chargers to charge up those batteries. Basically you guys get the hint.

[Mike90250]

Running that beast, with those specs, will cost you $.
Does it plug into a regular outlet, or is it hardwired? I ask because you should plug it into a kill-a-watt meter for a week. Then tou will have
a better idea how painfull it will be

[inetdog]

I was wondering if anyone can answer this. My brake lathe motor has a single phase motor. It reads 115voltage and pulls 11.4 continuous amps. Now with that being said , how many amps is that an hour or is that the hour amperage. Im new to this and would like to go completely solar. So im trying to find out how many batteries I would need at what amperage, what kind of batteries, how many solar chargers to charge up those batteries. Basically you guys get the hint.

I get the hint, but I am not sure I have all of the information. And I can't tell you all about the batteries, panels, chargers, etc without getting some other stuff out of the way.

1. Amps are current, the speed at which electrical charge is moving through the wires. If the motor actually pulls 11 Amps for one hour, that would be 11 Amp-hours (but that is not what you need to know!) At 120 volts (I like round numbers) that is 11 x 1 x 120 + 1320 watt-hours. Also known as 1.32 kilowatt-hour, or 1.32 kWh. That is what your inverter would have to deliver. If you use a 12 volt battery, sending 11 amps to the motor will take at least 130 amps from the battery. 12 volts x 130 Amps is 1560 watts. For one hour, that would be 1.56 kWh. That is bigger than 1.32 because the inverter is not 100% efficient at converting from one form of energy to another. And by the way, 12 volts is probably not the best way to go. More on that later.

2. The next question is how long you want to be able to run your lathe in one day. That will determine how large your battery has to be to run the lathe at night or on a cloudy day. Just for a start, one hour running the lathe will take 130 Amp-hours (130 Amps x one hour) from the battery. To keep your battery healthy, that should be 1/5 or less of the total battery capacity. So one-hour without recharging equals a 650 Amp-hour battery. If you used 48 volts for your battery bank, that would only need 4 12-volt 162 AH batteries. Or 8 81 AH batteries. (You see why I said 12 volts might be a bad idea?)

3. Next complication: Even though the nameplate says 11.4 Amps, the motor will only require that when running at full load. If the lathe is not being heavily loaded, you could be using far less power than 120 x 11.4 watts. The 11.4 Amps is the Full Load Amperes.

4. Really big complication: Depending on the type of motor it is, it could take between two and 10 times the rated Full Load Current to get it started. That would only be for a short time, but the inverter and battery bank still need to be able to handle it. The approximate starting current may be listed on the nameplate as the Locked Rotor Amps.

5. How many days of solar charging would go by before the next time you feel like using the lathe? Summer only, or in the rainy season too?

Once you have all of those answers at least roughly approximated, you will be ready for the next step.

[Sunking]

My brake lathe motor has a single phase motor. It reads 115voltage and pulls 11.4 continuous amps.

OK all that means is the motor uses 115 volts x 11.4 amps = 1311 watts. If that was supplied by a 12 volt battery, the current would be roughly 1311 watts / 12 volts = 109 amps.

We cannot answer your question what it would take to run it from solar because you have not provided enough information. Most importantly how many hours per day you run the lathe, your location, and time of year use.

What I can tell you it would be stupid to try to run the lathe off solar battery. For each 1 hour per day you run the lathe will cost you approx $3000 in equipment. $1000 of that is in batteries that would need replaced every few years. So if you run that lather 8 hours a day to make a living, your are looking at $24,000 initial cost, and about $8000 more every few years to replace the batteries.

[Mike90250]

If you are running your lathe anywhere near the grid, the best option, is Grid-Tie. Back feed the grid a little bit all day, and that unwinds the meter enough that the lathe, when running, does not increase your bill. But to zero out your bill, will take a $15,000 system. Even more to go completely off the grid with batteries only.

[Brakes]

I get the hint, but I am not sure I have all of the information. And I can't tell you all about the batteries, panels, chargers, etc without getting some other stuff out of the way.

1. Amps are current, the speed at which electrical charge is moving through the wires. If the motor actually pulls 11 Amps for one hour, that would be 11 Amp-hours (but that is not what you need to know!) At 120 volts (I like round numbers) that is 11 x 1 x 120 + 1320 watt-hours. Also known as 1.32 kilowatt-hour, or 1.32 kWh. That is what your inverter would have to deliver. If you use a 12 volt battery, sending 11 amps to the motor will take at least 130 amps from the battery. 12 volts x 130 Amps is 1560 watts. For one hour, that would be 1.56 kWh. That is bigger than 1.32 because the inverter is not 100% efficient at converting from one form of energy to another. And by the way, 12 volts is probably not the best way to go. More on that later.

2. The next question is how long you want to be able to run your lathe in one day. That will determine how large your battery has to be to run the lathe at night or on a cloudy day. Just for a start, one hour running the lathe will take 130 Amp-hours (130 Amps x one hour) from the battery. To keep your battery healthy, that should be 1/5 or less of the total battery capacity. So one-hour without recharging equals a 650 Amp-hour battery. If you used 48 volts for your battery bank, that would only need 4 12-volt 162 AH batteries. Or 8 81 AH batteries. (You see why I said 12 volts might be a bad idea?)

3. Next complication: Even though the nameplate says 11.4 Amps, the motor will only require that when running at full load. If the lathe is not being heavily loaded, you could be using far less power than 120 x 11.4 watts. The 11.4 Amps is the Full Load Amperes.

4. Really big complication: Depending on the type of motor it is, it could take between two and 10 times the rated Full Load Current to get it started. That would only be for a short time, but the inverter and battery bank still need to be able to handle it. The approximate starting current may be listed on the nameplate as the Locked Rotor Amps.

5. How many days of solar charging would go by before the next time you feel like using the lathe? Summer only, or in the rainy season too?

Once you have all of those answers at least roughly approximated, you will be ready for the next step.

Wow, I did not know that there was this much info you needed lol. I want to run the lathe for 2 hours a day for five days a week. My business is a mobile auto repair shop basically on wheels. There is alot of times in which I do not run it but maybe every other day. Im just trying to play it safe by saying 2 hours a day incase of a busy week.
This what I have right now

1. aims 12v 5000w inverter
2. 2 12v deep cycle marine batteries
3 8amp solar charger

I guess thats why I stuck with using a 6500 watt honda generator that works well. Just trying to get away from the noise and go solar. Im in Baltimore Md so in the summer we get 12 hours of sunlight. Winter about 8 , that is of course depending on the weather.

If its going to cost a bundle to set this up then I might just be sticking with the generator. If you were going to do this though , can you please tell me what you would use to power this monster. lol

I also have t5 flourescent tubes for lights which Im about to change to LED's . I know that LED lights do not draw much amperage at all.

Thank you for your reply

Rich

[Sunking]

If its going to cost a bundle to set this up then I might just be sticking with the generator. If you were going to do this though , can you please tell me what you would use to power this monster. lol

Well unless this Van you speak of is an 18 Wheeler Tractor/Trailer combination it is not large enough to hold all the solar panels required of roughly 1000 to 1500 watts.

If the motor was not so dang large I would suggest you just you replace the vehicle alternator with a larger one, and add a couple of auxiliary batteries. But with the lathe pulling some 1300 to 1500 watts would likely start a fire at some point in the future if not properly designed, installed, and maintained. My advice is stick with the generator.

[Mike90250]

...My advice is stick with the generator.

I concour. Solar or even batteries powered by your vehicle alternator, would require a $2000 inverter to spin the motor.

And beware the LED flrscent tube replacemets. They are not alwsys what the sales drois says they are.

[inetdog]

I concour. Solar or even batteries powered by your vehicle alternator, would require a $2000 inverter to spin the motor.

And beware the LED fluorscent tube replacements. They are not always what the sales droids says they are.

Running off at the mouth:
The efficiency difference between LED and CFL is still pretty small, with more potential for the LEDs to improve. But it is easier to make a dimmable LED unit than a dimmable CFL and they usually do not require special dimmers.
If you need good color rendition for your work, then only a few LED units will do as well as the better CFLs. For spinning machinery situations, the strobe effect seems to be about the same for both.
A two tube fluorescent fixture can be obtained with a different reactance for each tube to reduce strobe effect. Best in that respect though is a three tube three-phase fixture.
Costco featured some very low cost LED 120V replacement lamps, a few years ago but had to recall them because the only lasted a few months in constant use before the light level was down to 10% or less of the original. A name brand should not have that problem.
12 volt LED units versus 12 volt fluorescents are a smaller market on both sides and subject to a lot more variation.