How does the battery capacity calculate based on the load power?

Battery capacity is usually expressed in terms of "A/H". Such as:for example,20A / H, ismeans that1 amp discharge,ingcan bemaintained for 20 hours, discharge2 ampsdischargingcan bemaintained for 10 hours. Some are marked with the maximum discharge current, such as: 10A12V battery * 10A = 120W. As long as the electric appliance is not larger than this power, it can be driven.

The capacity of the battery is usually expressed in amps and hours (abbreviated as AH, 1A.h=36000C). The calculation formula of battery capacity C is C=I∫t0tdt. The battery capacity is divided into actual capacity, theoretical capacity and rated according to different conditions capacity.

The minimum capacity to be discharged at a certain discharge rate at 25 ° C to the termination voltage is the capacity of the specified battery at the time of design and production. This is called the rated capacity of a certain discharge rate RH.

The battery capacity is generally calculated in AH (ampere-hours), and the other is calculated in CELL (unit plate) several watts (W). (W/CELL) 1. AH (ampere hour) calculation, defined as 20 hours. For example, a 7AH battery refers to a continuous discharge current of 0.35 A for 20 hours.

2. W (W (consumption power) / CELL (unit plate)) calculation, the definition is based on 15 minutes. For example, 1221W battery is 12V (6CELL), each CELL power supply 21W can supply power for 15 minutes.

3. The charging time is based on 10 hours, and the charging current is 1/10 of the battery capacity. Fast charging will reduce battery life. Battery capacity refers to the amount of battery storage. The unit of battery capacity is “mAh”, and the Chinese name is mAh (when measuring a large-capacity battery such as lead storage battery, for the sake of convenience, it is generally indicated by “Ah”, the Chinese name is Anshi, 1Ah=1000mAh). If the rated capacity of the battery is 1300mAh, if the battery is discharged with 0.1C (C is the battery capacity), that is, 130mA, the battery can work for 10 hours (1300mAh/130mA=10h); if the discharge current is 1300mA, then the power supply The time is only about 1 hour (the actual working time varies depending on the individual differences in the actual capacity of the battery). This is an analysis under ideal conditions. The current when the digital device is actually working cannot always be constant at a certain value. (In the case of a digital camera, the operating current will be large due to the opening or closing of components such as the LCD display and flash. Change), so the battery can only provide a certain value for the power supply time of a device, and this value can only be estimated through practical experience.

Technical parameters about the stabilizer.

A, the regulator has an input voltage adaptation range. The IEC standard changes the input voltage within ±10% of the rated value. The input range of our products is ±15%. The out-of-range automatic sound and light alarm does not stabilize the output voltage within the required range.

B, the output voltage regulation rate is the effect of the change of the input voltage caused by the change of the input voltage. When the load is the rated value, the input voltage is adjusted upward from the rated value to the upper limit value and the lower limit value according to the source voltage range, and the measurement is performed. The maximum amount of change in output voltage (±%). The smaller the value, the better, is an important indicator of the performance of the AC voltage regulator.

C, load adjustment rate: is the effect of changes in output caused by changes in output. Change the load current and measure the amount of change in the output voltage (±%). The smaller value is better, which is an important indicator of the performance of the AC voltage regulator.

D, the relative harmonic content of the output voltage (also known as the output voltage distortion), usually expressed by THD, is the ratio of the total effective value of the harmonic content to the effective value of the fundamental wave. When the load is rated, the input voltage distortion satisfies the reference. When the condition (generally less than 3%), measure the output voltage distortion when the input voltage is the lowest value, the rated value and the highest value, whichever is the largest. The smaller the value is better.

E, efficiency: is the ratio (percentage) of the output active power P0 to the input active power Pi,

F, load power factor

The regulator capacity is expressed in terms of volt-amperes (VA) or kVA (KVA). In addition to the purely resistive load, there are inductive and capacitive loads in the load, that is, in addition to the active power in the load, there is no Power. This pointer reflects the ability of the AC regulated power supply with inductive and capacitive loads.

Generally, the AC regulated power supply has a load power factor of cosφ of 0.8. When the product is 1KVA, the output active power (ie, the capacity of the resistive load) is up to 800 W. If the product is expressed in 1 kW (cosφ is still 0.8), the output active power is 1KW, and the power that can be output is S=1000/0.8=1250VA. When the value of the load power factor is small, it indicates that the power supply device has a strong ability to adapt to the reactive load.

G, AC regulator parameters are also output power, input frequency, source frequency effect, random deviation (time drift), no-load input power, source power factor (this value is different from load power factor, hopefully the bigger the better, the maximum It is 1), source current relative harmonic content, audio noise, etc., three-phase AC regulated power supply, and three-phase output voltage unbalance. The definition and test methods of these pointers can refer to relevant standards.

1. Get the current of the electrical equipment first.

2. Dividing the battery capacity by the current of the powered device is the length of time that can be used.

A 3000mAH, rated voltage 5V battery is powered by a 2.5W, 5V power supply. Its theoretical duration is:

I=P/U=>2.5w/5v=>0.5A=>500MA, 3000mAh, that is, 3000MA current can be discharged for one hour, 3000/500=6 hours.

Battery capacity is one of the important performance indicators to measure battery performance. It indicates the amount of electricity discharged by the battery under certain conditions (discharge rate, temperature, termination voltage, etc.) (discharge test can be performed with JS-150D), that is, the capacity of the battery, usually Ampere hour is the unit (abbreviated as A?H, 1A?h=3600C).

The battery capacity is divided into actual capacity, theoretical capacity and rated capacity according to different conditions. The calculation formula of battery capacity C is C=∫t0It1dt (integration of current I from t0 to t1), and the battery is divided into positive and negative poles.

Concept:

1. “mAh” is the unit of battery capacity. When the Chinese name is mAh (when measuring large-capacity batteries such as lead storage batteries, for the sake of convenience, it is generally indicated by “Ah”, the Chinese name is Anshi). 1 mAh = 0.001 amps * 3600 seconds = 3.6 amp seconds = 3.6 coulombs.

2. Coulomb is the unit of electricity. Coulomb is not the basic unit of the International System of Units, but the unit of export of the International System of Units. 1 coulomb = 1 ampere per second. The amount of 1A current transported in 1s, ie 1C = 1A.s.

3. Calculation formula of electric power: P=UI. The unit of P is W; in the purely resistive circuit, it can also be obtained by substituting Ohm's law U=IR into P=UI: P=I*IR=(U*U)/R.

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