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How does a solar charge controller work?

In this article we will talk about an important device in a solar energy system, the charge controller: you will learn how a solar charge controller works

How does a solar charge controller work?

A solar charger controller is a solar electrical component that mainly controls the amount of energy coming from the solar panel to a power bank. It is a voltage and current controller so that the battery is best maintained at its maximum efficiency during use. That being said, how does a solar charge controller work?

Basically, it acts as a protection tool that makes sure a bank is not overcharged during the day. At night, the energy capacity of the bank does not decrease, which leads to eventual drainage.

The principles of a solar charge controller

This renewable energy component is governed by the scientific and electrical principles listed below:

1. Power management

The solar charge controller  can save your module and power system from early degradation. In its configuration, it includes light-emitting diodes (LEDs), alarms and beeps to notify users in the different stages of use in an appropriate way.

An example of an LED used in the setup includes a solar charge LED that indicates whether current is flowing from the solar panel to the power bank. Failure to turn on despite apparent reasons can be attributed to loose wires, cell module deficiencies, bad battery, or circuit disconnection.

Other LED components include Low Battery and Full Battery LEDs. These respectively indicate the health of the bank by illuminating the low and high charge states. A low battery LED suggests that you stop or reduce the use of the cell as soon as possible to avoid its eventual degradation when draining. The full battery LED, on the other hand, lets you know that the battery is fully charged and ready to go.

2. Low voltage disconnection

solar charge controller operation

Low voltage disconnect is a feature of a solar charge controller that automatically disconnects the charge from the battery when the battery falls below the minimum power threshold. It also helps in continuously monitoring status uploads each time.

An example of this is when a device is used too much and the power ratings are higher than the battery. The LED lights up to indicate that the battery cannot support continuous use of the device. The LED also indicates that an additional charge is needed to bring the charge status back up. Reconnection is achieved when the minimum energy threshold is sufficiently reached.

This function helps you to choose the suitable drivers available in the market. It is essential that in the selection process, the voltage disconnect is measured in terms of the various loads used in the current home or space. You may eventually find that the component becomes useless as disconnects are experienced each time shortly.

Some of the best Amazon buys include HQST ​​30 Amp, ALLPOWERS 20A, and Morningstar SunSaver. The features of these items include adjustment to different voltage thresholds that is convenient for you as a user. Also featured in this video is a buyer’s guide that can help you explore your needs as a consumer.

3. Overload protection

If a safety feature is included in the configuration when the power level of the bank is too low, then in high power states a management component is also employed. Battery overcharging can be achieved by reducing the current entering the module. In science, this is specifically referred to as trickle charging, which means that small doses of electrical charge are gradually charged to the battery without having to cause gas in the setup.

Another principle that governs this feature is the automatic loading of the cell for periods of time. After trickle charges are hinted at in the final stages, charging automatically ceases and stops battery module functions completely. This relieves your burden as a consumer of continually keeping an eye on your settings to preserve battery health.


A solar charge controller is a useful component in maintaining the health of your batteries. It mainly provides three functions:

  • Provide a connection point from the power source to the energy storage unit.
  • Reinforce the efficiency of battery health by managing the energy input that enters the system through protection against overload, drain and constant fluctuations in voltage levels, and
  • They allow to locate problems immediately by incorporating alarm and lighting systems.

As a consumer, it always helps in the selection to be attentive to the characteristics of  solar products  , such as threshold voltage, so that it works in a compatible way with your available appliances. There are a host of Amazon products available with consumer friendly features to help you save power and battery health. Lastly, this should be supplemented by reading the user manuals and following the buyer’s guide for efficient use.