As solar panel systems are being understood and used in more and more homes, out of the need to reduce the cost of post-solar panel system maintenance, or the expectation of choosing the solar panel system that best suits their needs, more and more people are getting into the basics of solar panel systems, as well as other electrical systems.

In this article, we will introduce you to the units of measurement of two common physical quantities, milliamps and watts, as well as the formulas that make the conversion between the two possible. This will help you better understand solar panel systems.

Before learning the conversion formula between the two, first we need to recognize the following physical quantities.

1. What is milliampere (mA)?

Milliampere is the unit of current (I) in an electric circuit, symbolized as mA. It is usually used to describe the magnitude of current in an electric circuit. From a microscopic point of view, it expresses the amount of charge that passes through a section of a circuit in an instant, i.e., the rate at which the current passes through a section.

It is important to note that the milliampere is not the primary unit of current. When describing the amount of current in a circuit, its primary unit is usually used: the ampere (A). Ampere and milliampere meaning, usage are the same, and the two belong to the same physical unit of measurement, can be directly converted through the International System of Units in the multiplier relationship, the two conversion formula:

1A = 1000mA

1mA = 0.001A

2. What is a watt (W)?

Watt is the unit of power, but also all kinds of electrical systems in the most widely used electrical physical unit, usually used to describe some kind of electrical appliances to complete some kind of work in the amount of energy to be consumed. The more energy the appliance needs to do its job, the greater its wattage, and conversely, the less energy it needs to do its job, the smaller its wattage.

Watt can also be used to describe the power generated by a power generating device, e.g. the wattage of a solar panel system refers to the power generated by the solar panel under ideal conditions.

3. How do I convert from milliamps (mA) to watts (W)?

First of all, the conversion from milliamps to watts requires that two impeding conditions between the two be met first:

One is that the milliampere is not the primary unit of current measurement, and it is not of the same class as the watt. Therefore, when converting from milliamps to watts, milliamps need to be converted to amperes first.

Secondly, although both milliamps and watts are units of measurement of physical quantities in electrical systems, they are not the same kind of unit of measurement of physical quantities, so in order to realize the conversion of the two, we need to introduce an intermediate unit of measurement of physical quantities, that is, volts (V).

In order to overcome the above two hindering conditions, we need to achieve the conversion between the two through the following steps.

First, we need to convert milliamps to amperes, and according to the International System of Units, the conversion relationship between the two is:

1mA = 0.001A

Second, we need to achieve the conversion from amperes to watts by means of an intermediate physical quantity: volts (V), which is converted by the following formula:

P (W) = V (v) x I (A)

The complete conversion formula can be synthesized through the above two steps, and the specific conversion formula for milliamps to watts is:

P (W) = V (v) × {I (mA) ÷ 1000}

In order to facilitate your better understanding and mastery of the above formula, the following will be used as an example of actual electrical appliances, to give you an example of the application of the above formula. Assuming that the operating current of an appliance is 1200mA and the operating voltage is 110v, the power of the appliance is:

110v x (1200mA ÷ 1000) = 132W.