How Many Watts Does A Car Battery Charger Use?

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For the sake of persons like myself who probably did not pay much attention to their physics class, a watt is the unit of power and determines how many amps the car battery charger puts out. Hence, before replacing the battery charger, its watts must be seriously put under consideration.

So, how many watts does a car battery charger use? some flashback at elementary physics is required to answer this question correctly.

Do you remember the relationship between power, voltage, and amperage? Well, I do. So, let’s take a look at it.

Power is given as the product of voltage(volts) and current (amp), that is, V X I = power (watt). Therefore, to determine how many watts a car battery charger uses, these two variables, that is, current and voltage must be known.

With this in mind, it is understandable why a 10 amp 12-volt charger uses 120 watts of power based on the formula of power stated above.

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How to determine how many watts a car battery charger use?

Knowing how to determine how many watts a battery uses is important in the decision-making when you plan to get yourself a new battery charger. The charger’s power rating tells exactly how many amps of charge it puts out. Except for good reasons, it is best to stick with the power rating of your previous charger. 

Stepping up to a charger with a much higher power rating and consequently a higher charge output could lead to the battery plates getting damaged at some point.

The formula power ( watt) = V*I sums up the entire relationship between power, voltage, and current or charge. This way, either of the parameters can be calculated in simple mathematical steps.

To fully understand the concept of power a charger uses, learning about the various types of battery chargers there are, is equally important. Charger types commonly used amongst car owners include the simple type of charger which as the name implies has a simple charging mechanism.

The simple charger simply continues to send in a constant amount of direct current into the rechargeable battery and continues to do this until it creates a charge and gets the battery fully charged. The trickle charger on the other hand sends in a low current. The trickle charger can be used to restore the charge in small batteries as well as the big types.

Other types of t chargers are the timer type of charger and the smart charger. The timer charger is easy to understand. How it works is embedded in its name. You start by presenting a particular time duration, the charger then charges the battery up until the present time.

Of all the types of chargers, the smart charger is most likely the best, especially at avoiding the battery getting overcharged. The decision to get any of the charger types is influenced by the simple charger being affordable more than others, the trickle charger is ideal for charge replenishment, and the smart solving the long-standing issue of overcharging associated with battery chargers.

Remember that the wattage or rating of a battery charger is only achievable at its highest ot maximum performance which is rarely attainable except when the right scenario is created such as when the charger is being tested for efficiency. Some of the watts from what is stated as the chargers rating for the heat generated during the charging process. 

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How many watts does a 12-volt battery use?

This again brings us back to the mathematical relationship between power in watts, voltage in volts, and current in amps. For a 12-volt battery, the watts can be easily calculated using the stated amperage rating.

Most batteries are rated 48 amps and discharge 1 amp let hour. If that is the case, then the watt of a 12-volt battery can be calculated in the following way.

Watt= 12 volt X 48 amps

Power= 576 watts.

Irrespective of what the rating is for any given battery or charger, the values for its voltage and charge can be substituted into the formula and any of the parameters can be easily calculated afterward.

How many amps does a car battery need?

Car batteries have a standard voltage as well as amperage rating. This is usually by the electrical load of such h car. It is therefore important to learn about your battery rating each time there comes a need to get the battery replaced. The commonest amperage rating of batteries is 48 amps while the voltage rating is 12 volt.

How to use a car battery charger?

I believe every road user should learn the proper way to make use of a car charger. while this may not be considered necessary knowledge by those who have never experienced a dead battery, I say it is only a matter of time before this happens.

The highest consumer of battery charge is turning the car engine on. When you are frequently engaged on trips that turn off the car and turn it on every once in a while, it quickly saps out charge from the battery.

Also, when accessories such as heaters and air conditioners are constantly being used, such a car may eventually come down with a flat dead battery as the charge consumption is unmatched with what the alternator is providing.

In this state, your only savior will be a battery charge. Not knowing the proper way of making use of the charger will put you in a precarious situation. Here is how to make use of a battery charger correctly.

The first question to ask yourself is how many amps of current are found in a car battery? Why is this necessary? Well finding out how many amps there is in a fully charged battery will help us decide how long it will take a given charger to get the battery fully charged

Most car batteries are 48 amps batteries. Chargers on the other hand differ in terms of their charge output. There are 2-amp chargers and others with a charge output as high as 10 amps. The charge output of a given charger decides how long it takes to get the battery fully charged.

While most people will naturally desire to make use of a charger with high output charge such as the 10 amp charger to reduce the charge time. this may however not be such a great idea as it puts the car battery plates at risk of damage.

So, how is the battery charger connected to the battery? First, before attempting to establish this connection the car battery electrolyte level should be evaluated.

This is because it is unsafe to plug a car with a suboptimal level of electrolyte into a charger. if after checking the level of the electrolyte, it is found to be below what is required, this should be adequately augmented before connecting the charger.

The next step will be to disengage the car alternator from the car battery about to be charged. this is because, older versions of alternators are designed in such a way that if left connected to the car battery while the battery is being charged, it could get severely damaged, requiring to be replaced.

The next step will be to connect the terminals of the battery charger to those of the battery. However, before this is done, ensure to clean the battery terminals properly as they tend to get corroded over time. the chargers’ clamps are color-coded with the positive clamp being colored red and the negative black.  Make sure to inspect the car battery closely to ascertain the positive and negative posts. The clamps are then connected appropriately.

When this connection is properly secured, the car battery charger is then plugged into the main power outlet and turned on. the rating of such a charger determines how long it will take to get the battery charged.

The standard and most likely the most popular type of charger will charge at about 2 amps by the hour, meaning, it takes about 24 hours to get the battery fully charged.

The charge rate and amount of charge can be observed on the ammeter

Part of the precautionary measures when using a battery charger will be to ensure the terminals are not removed first before the charger is unplugged. It should be the other way around, that is, the charger should first be unplugged before the terminals are removed to avoid getting sparks.

Some chargers are designed to charge at more than one charge. The commonest type of such charger is those which can charge at both 3 amps charge output and 6 amps depending on the settings.

An eye should be kept on the gauge to make sure the battery is adequately charged and never overcharged. Thankfully there is also an indicator or warning light to learn about the charge state of the battery.

How Many Watts Does A Car Battery Charger Use – Conclusion

Watt depicts power and determines the amps the charger puts out making it an important parameter especially when looking to replace your old battery charger.

Thankfully, with the standard mathematical relationship that exists between power, voltage, and charge, this can be achieved easily.

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