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How long will a battery with a 30 ampere hour rating supply a 240 Watt load?
Wiki User
∙ 9y ago
The Ampere-Hour rating tells you how much energy can be extracted from a given battery. For our 30AH battery, you could draw 1A for 30 hours, 2A for 15 hours, 3A for 10 hours, 30A for 1 hour, or any combination where Amps X hours = 30, within reason. Are you talking about a battery supplying a load directly, like a 12V battery supplying a 240W, 12V heater? Or do you mean a battery running an inverter supplying a 120V, 240W load? For the direct load, first calculate Amps drawn by the load. Amps = Watts / Volts. Then divide the A/H rating of the battery by the load Amps. Example: * 240W, 12V heater * Amps = 240 / 12 = 20A * Time = 30AH / 20A = 1.5 hours (90 minutes) For a load run by invertor, you just divide the Watts needed by the efficiency of the invertor. The efficiency rating is almost always found on the nameplate or in the manual. Most modern invertors are in the range of 90% - 96%. Example: * Same as above, except load is 120V, 240W heater run through a 90% efficient invertor. * Watts drawn from battery = 240 / 0.9 = 267 W * Amps = 267 / 12 = 22.2A * Time = 30AH / 22.2A = 1.35 hours (81 minutes) One factor to consider: The Amp-Hour rating of a battery is only valid up to about 10% of capacity current draw. So, a 30AH battery is only 30AH for loads up to 3A. At very high loads, the available AH from a battery decreases. This derating varies with size and manufacturer, but don't count on getting every minute of operation from our example above, because our current draw is much higher than 3A. In this case we might only have 25AH or so to play with.
Wiki User
∙ 15y ago
Wiki User
∙ 9y agoTo solve this, you need to get everything into the same electrical units. Since we
are dealing with ampere-hours, convert the load rating in watts to amperes.
Watts = volts X amps. If you turn the formula around using simple algebra,
you have Amps = Watts/Volts.
So, if your battery voltage is 12 volts, 240watts/12 volts gives you 20 amperes.
If the battery is rated at 30 ampere-hours, this means that the battery would
supply 30 amperes for one hour, or 15 amperes for 2 hours, ... or 1 ampere for
30 hours. So a 30 ampere-hour battery supplying a 20 ampere load would last
for 30/20 of an hour, or 1.5 hours. At that time the battery would be totally
discharged.
Notice the second " if " above. That's the point that you need to dwell on.
It says that the answer to your question depends on the battery voltage.
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How long will a battery 12 ampere-hour rating supply 144 watt load?
An ampere-hour rating is a relatavistic indication of how long a battery can supply a specific current.It is not possible to determine the run time when you only gave watts, but watts are volts times amps, and you did not supply the volts.
What is the ampere rating for a 12 volt 12 watt battery?
Batteries are generally not listed as having watts. And there are a couple of different ampere ratings. But if you're running something needing 12W of a 12V battery it's pulling 1A out of the battery at the moment.
How long will a 1 watt bulb operate on a 1 amp hour battery?
Please give the voltage and Ah rating of the battery and voltage rating of bulb.
What does it cost to charge a battery?
If the national average cost of consumer electricity is 13 cents per kilowatt hour and you are attempting to charge a 12 volt 70 amp hour car battery, then the cost of charging the battery may be calculated. The battery is imperfect and will require about a third more than its ampere hour rating to fully charge it. Assume it will take 100 ampere hours to charge the 70 ampere hour battery. At a charge voltage is necessarily above the battery voltage, usually at about 16 volts, and 100 ampere hours, the result is 1600 watt hours or 1.6 KWH The cost is then 20.8 cents to charge the battery calculated from 1.6 KWH times 13 cents per KWH.
How long would a 1500 watt space heater run on a 2000 watt dc to ac power invert?
It depends on the source of DC that is powering the inverter. Since the inverter is 2000 watts, that just means it will handle your 1500 watt application. At 120 VAC you are drawing a little over 12 Amps. If this is an inverter plugged into a car it will run until the battery runs down, whose time will be lengthened if you keep the car running. Your battery will have an Ampere per Hour rating. If for example you had a 50 AHr battery it could supply 50 Amps for an Hour so your heater would run for about 4 hours.
How long can a battery power a 44 watt light bulb?
To answer this question the amp hour rating of the battery is needed along with the voltage of the battery or bulb.
How long does it take to charge the Super Turbo 800 Watt elite?
Depends on the battery's mAh rating and what the charger's mA rating is. Say the battery is a 1000mAh Lipo battery and the charger puts out 500mA, the battery will charge in 2hours.
How many amp hours in BXT-65-650 battery?
Difficult. The manufacturers of car batteries have become extremely coy about the performance parameters of their products, probably because they don't want to be forced to meet them by a court. However, I would suspect that it would be in the vicinity of 30-40 ampere hours. That means that it can deliver 30-40 amps for one hour, so at a voltage of 13.2 volts, that means 396 - 528 watt-hours, ignoring the fact that the voltage decreases as it discharges. The "Cold cranking" current is a red herring...that is just the current it can supply for a short time, limited by the internal resistance of the battery. <<>> Battery manufactures have gone to a Reserve Capacity rating which is more realistic than using the Amp-Hour rating. Reserve capacity is the number of minutes that a battery can maintain a useful voltage under a 25 ampere discharge at a temperature of 25 degrees C. To maintain a high RC number a battery requires higher quality cell materials. The RC rating of a BXT-65-650 is 130. To convert RCR (Reserve Capacity Rating) to Ampere-Hours at the 25 amp rate, multiply RCR by .4167.
How many hours can we run a 1500 watt item off of one 24 volt battery?
First the amperage of the 1500 watt device has to be established. I = W/E. Amps = Watts /Volts = 1500/24 = 62.5 amps. To answer this question the amp/hour rating of the 24 volt battery has to be stated. This is the capacity rating of the battery. Take that rating and divide it by 62.5 amps will give you the amount of hours that the battery will take before it drains and needs to be recharged.
How do you get ampere hour from watt hour?
Watt = ampere x volt. So if you know the voltage, you can convert amperes to watts or vice versa. If not, you don't have enough information.AnswerThe ampere hour (A.h) is a unit of measurement for electric charge (the SI unit being a coulomb). The watt hour (W.h) is a unit of measurement for electrical energy (the SI unit being a joule).In the case of cells and batteries, if you multiply its capacity (in ampere hours) by the voltage, then you'll have its capacity in watt hours.
How many vA equal to 1watt?
In a.c. circuits, the watt is used to measure the true power of a load, and is determined by multiplying the supply voltage by the load current by the power-factor of the load. The volt ampere is used to measure the apparent power of a load, and is determined by multiplying the supply voltage by the load current. So the relationship between the watt and the volt ampere depends on the power factor of the load. For example a 100 VA load with a power factor of 0.8 (leading or lagging) will have a true power of 80 W.
How many 9 watt bulbs can an 14 amperes 12 volt battery support?
Batteries are normally specified in ampere hours. A 12 v battery could be specified as 14 A-h or 14 ampere-hours, which means 14 amps for 1 hour, or 1.4 amps for 10 hours. In other words it produces less current for a longer time. A 9 watt bulb takes ¾ amp in theory, so it should last 14/¾ hours on that battery, that is 14 x 4 / 3 hours, 18 hours. Or two of the same bulbs for 9 hours, etc.
