Each component in a solar power system is dependent more or less on the other. Solar panels produce high-voltage power that is transferred to solar inverters and batteries. This direct current traveling from solar panels sometimes has a much higher voltage than the maximum voltage that a solar inverter or battery can handle. As a result, it may also damage them. This is why we need protective devices and solar charge controllers are one of them. Yes, you may have heard about charge controllers and this article is dedicated to the best PWM solar charge controller. Apart from this, you will get to know about factors to consider while buying the best solar charge controllers.
What is a Charge Controller?
A device regulating incoming solar energy from solar panels to charge a solar battery is known as a solar charge controller. There are usually 4 types of solar charge controllers, namely series regulator, shunt regulator, MPPT, and PWM charge controller. Here is a brief description of all.
1. Series regulator: They open the circuit between the solar panel and battery once it reaches an optimum voltage. It maintains the circuit until the battery reaches the disconnect voltage again.
2. Shunt regulator: They function by short-circuiting a solar array once the battery reaches a set voltage and once the battery reaches back to its optimum voltage, the circuit is reconnected.
3. MPPT: The Maximum Power Point Technology charge controller tracks the point around the voltage and current curve where the output from solar panels is max. It requires more integrated chips and components. Once it detects the point, it lowers the PV panel voltage using a step-down converter to match the battery voltage.
4. PWM: This charge controller uses the Pulse Width Modulation technology that works by connecting and disconnecting the power source to load, that too very swiftly. It basically controls how long the switch remains on, such as regulating the amount of power supplied. It cannot regulate voltage like an MPPT controller, but it acts like a gate to the voltage. In this sense, it limits the amount of time for which the battery and solar panels are connected.
5 Best PWM Solar Charge Controller
Let us get to know in detail about the best PWM controllers.
1. Renogy Wanderer 30A
This PWM charge controller from Renogy is featured with several in-built safety features, but they do not make it’s handling any complex. The overcharging protection feature of Renogy Wandered 30A protects the solar power system and increases the lifespan of your solar battery. You can add a battery temperature sensor to improve temperature compensation. This feature is hardly found in PWM charge controllers, but this temperature sensor port is crucial for your solar battery if it experiences frequent and wide temperature swings. With its easy-to-understand LED indicators monitoring becomes easy.
Wanderer 30A is compatible with gel, sealed, lithium, and flooded batteries whereas most other PWM controllers work on lead acid batteries. And being affordable, this charge controller is the top best choice among PWM charge controllers. Also, this controller is ideal for 12V batteries and is capable of handling around 400 watts of solar energy.
However, if you want to keep a check on parameters like battery voltage and current, you could purchase Renogy BT-1 Bluetooth Module. With it, you can monitor your solar power system from your Smartphone. Specifications of Renogy Wanderer 30A are as follows:
- Battery compatibility: Sealed, gel, flooded, lithium
- Bluetooth monitoring: Yes (requires additional purchase)
- Charge current rating: 30A
- LCD display: No
- Max. PV open circuit voltage (Voc): 25V
- Nominal battery voltage: 12V
- Operating temperature range: -20 °F to 113 °F (-35 °C to 45 °C)
- Temperature sensor: Yes (requires additional purchase)
2. Renogy Adventurer 30A
It is like a combined model of both Renogy wanderer charge controller models. Renogy Adventurer 30A has an inbuilt temperature sensor port of Wanderer 30A along with an LCD display, and 12/24 V compatibility of Wanderer 10A. Plus it is Bluetooth compatible with a voltage sensor port along with a flush mounting. However, it can be surface mounted to a wall like other controllers as it comes with a surface mount attachment. This charge controller is compatible with 400 to 800 watts of solar energy.
Additionally, its Battery Voltage Sensor (BVS) helps in maximizing battery life when the controller and battery are not together in one place. With longer wire runs there is the possibility of voltage discrepancy between both components which is reduced by the Adventurer 30A controller. Though this one is among the best PWM solar charge controller and is a bit pricey, its futures justify the value.
- Battery compatibility: Gel, sealed, lithium, flooded
- Nominal battery voltage: 12/24V
- Charge current rating: 30A
- Operating temperature range: -13 °F to 131 °F (-25 °C to 55 °C)
- Max. PV open-circuit voltage (Voc): 50V
- LCD display: Yes
- Temperature sensor: Yes (requires additional purchase)
- Bluetooth monitoring: Yes (requires additional purchase)
3. Morningstar SunSaver
This PWM charge controller is from the SunSaver line and is durable with an excellent build. Backed with a 5-year warranty, Morningstar SunSaver provides some extra battery protection along with increasing its lifespan in the long run. Functioning on lead acid batteries, this charge controller is limited to flooded or sealed ones. With this PWM charge controller, it buys for a lifetime of choice.
SunSaver charge controllers using materials like marine-grade terminals along with an anodized aluminum case. This makes it more durable than other controllers. The built-in temperature sensor provides good voltage accuracy; however, there are models featuring Low Voltage Disconnect (LVD). Following are the specifications of SunSaver charge controllers.
- Battery compatibility: Sealed, flooded
- Nominal battery voltage: 12-24V (depending on model)
- Charge current rating: 6-20A (depending on model)
- Operating temperature range: -40 °F to 140 °F (-40 °C to 60 °C)
- Max. PV open-circuit voltage (Voc): 30-60V (depending on model)
- LCD display: No
- Temperature sensor: Yes (built-in)
- Bluetooth monitoring: No
Also Read: What are Different Types of Solar Charge Controller?
4. Renogy Wanderer 10A
This is an excellent budget option, but you do not have to compromise on efficiency. Renogy Wandered 10A is ideal for small solar systems and is compatible with 12V or 24V systems plus it has an LCD display for accurate monitoring. For a 12-volt system, it can handle up to 130 watts of solar power and for a 24-volt system, the maximum power range is 260 watts that it can handle. This much power is enough to run small devices like phones and laptops along with some lights.
Your 12-volt and 24-volt solar batteries can be charged with Wandered 10A. It has features like an LCD display and also 2 USB ports that can be used to charge phones or other USB devices. If looking for a better option at a considerable rate, then this PWM charge controller is the best pick. Following are the specifications of this best PWM solar charge controller.
- Battery compatibility: Gel, sealed, lithium, flooded
- Nominal battery voltage: 12/24V
- Charge current rating: 10A
- Operating temperature range: -31 °F to 113 °F (-25 °C to 45 °C)
- Max. PV open-circuit voltage (Voc): 50V
- LCD display: Yes
- Temperature sensor: No
- Bluetooth monitoring: Yes (requires additional purchase)
5. Allpowers 20A Solar Charge Controller
Known as one of the most cost-effective Allpowers 20A Solar Charge Controllers serves the purpose well. Even though it gets heated up quickly, this drawback does not stop it from doing its job. It has an LCD display and is particularly suitable for small power projects.
- Battery compatibility: Gel, sealed, flooded
- Nominal battery voltage: 12/24V
- Charge current rating: 20A
- Operating temperature range: -31 °F to 140 °F (-35 °C to 60 °C)
- Max. PV open-circuit voltage (Voc): 50V
- LCD display: Yes
- Temperature sensor: No
- Bluetooth monitoring: No
Also See: What Size Charge Controller for 200W Solar Panels?
Things to Consider While Choosing the Best PWM Solar Charge Controller
Now, that you know which are the best PWM controllers here is a list of things you should understand and consider while buying one for your solar panel system.
1. Battery Compatibility
Choose a charge controller that is compatible with the type of solar battery you have. Mostly all PWM models are compatible with lead acid, flooded, and sealed batteries. Whereas there are models that are compatible with even gel batteries and most versatile models are compatible with lithium batteries also, so choose accordingly.
2. Charge Current Rating
This rating must be more than the expected maximum charge current that will be supplied from the controller to the battery. But any charge controller exceeding the rating of the expected max current may result in a damaged charge controller. One more thing, this rating should be less than the maximum recommended charge current of the battery.
Basically, the charge current rating is written in Amps and mostly included in the product name. As for determining the best PWM solar charge controller, consider this rating crucial. For example, Renogy Adventurer 10A charges a battery at 30 amps, which is its charge current rating. If not mentioned in the name, it is listed on the product page or instructional manual (or both).
3. Solar Panel Current Rating
The next thing you need to do is to choose a solar panel system below the CCR limit. It is basically how much current your solar panel produces, which can be confirmed by its specifications label. It is written as short circuit current (Isc) in amps. For parallel connected panels, sum up the Isc current of all panels to determine the short circuit current for the entire array.
- Maximum PV Input Power: It is another rating to determine the maximum level below which your charge controller ratings should be. Most brands list this rating in watts for their charge controllers.
4. Maximum Photovoltaic Open Circuit Voltage (VOC)
Ensure that the VOC of the charge controller is not less than the VOC of solar panels. To calculate the VOC of your solar panels use a solar panel VOC calculator, then you can pick a charge controller with max PV voltage basically the one with a greater number than the VOC of PV panels. Here is a list of charge controller VO Cand with which they are most compatible.
- Less than 25V: It is rare that a PWM has this low voltage limit. But in rare cases, if you find one with a 25V or less voltage remember it is not compatible to be used with 12V solar panels.
- 25V-30V: PWM in this range can easily handle one 12V series wired solar panel. These charge controllers are designed to use 12V batteries and to add panels with batteries you need to change the wiring to parallel.
- 50V-60V: Around 1 to 2 series wired solar panels in 12V can be handled by controllers with this range. Moreover, they are designed for 12V and 24V batteries.
- More than 60V: However, a PWM above 60V is rare but models in this range are particularly capable of handling 3 or more series wired solar panels.
Also see: Connecting Solar Panels in Series Vs Parallel
5. Maximum Wire Gauge
For deciding among the best PWM solar charge controller, this specification is basically the wire size that is compatible with the terminals of a charge controller. This gauge allows more current to flow than the current rating of the PWM charge controller. It simply means you can over-gauge your wires for additional safety. Sometimes, wire terminals are considered a proxy for good quality.
6. Nominal Battery Voltage
It is necessary to have the same nominal battery bank voltage and a nominal voltage of the charge controller. Suppose you have a 12-volt battery, a solar charge controller with 12-volt batteries will be compatible with it. The same applies to 24-volt controllers which require 24-volt batteries. However, there may be some PWM models that are compatible with 12 and 24-volts both.
Also Read: What is Battery Cycle?
7. Operating Temperature Range
This range should suit the location you plan to install your charger controller. It is an important factor to consider because a pulse width modulation charge controller with a narrow operating temperature range may not be suitable for installation in buildings or vehicles lacking air conditioning. For example, Renogy Adventurer 30A has a -13 °F to 131 °F (-25 °C to 55 °C) operating temperature range. So, for this, you need to ensure that the installation location is not already exceeding this temperature range.
Note: Consider battery temperatures too while deciding on the charge controller for your solar power system.
8. Warranty
Another factor to determine which charge controller to choose is its warranty period. A charge controller with more years of warranty is considered to be the most reliable, but they are highly priced too. However, this depends on your budget and solar power system requirements as to which one is best. So, among all the options, some may not have any warranty, and a few budget-friendly options may have a 1 to 2-year warranty. Some brands offer 3 years or more warranty on their charge controllers.
Also See: What is Solar Panel Warranty?
9. Additional Features
Other than the following features, some additional ones can also be considered while purchasing a solar charge controller. LCD display, temperature compensation, and Bluetooth monitoring.
a. LCD/LED displays: It makes monitoring easy like having a glance at the charging current or PV voltage at the moment. LED indicators flashing at different speeds and colors indicate a distinct status of the system.
b. Temperature compensation: With the rising temperature of batteries, it is necessary to maintain charging current and voltage. This feature is important for batteries with wide temperature swings, and charge controllers carry out temperature compensation through built-in temperature sensors and temperature probes.
Also See: What is Ambient Temperature?
Here the former can monitor ambient temperature near the charge controller but if the battery is wired away from it, the reading will be different. For a more accurate battery reading, the latter can be taped directly to the battery. However, both these features do not work efficiently if either of them is missing.
c. Remote Bluetooth monitoring: With this, you can monitor and adjust your solar power system via a mobile application. Though it is most common with expensive MPPT solar charge controllers and is rarely seen featured in PWM controllers. But some PWM models do have inbuilt remote monitoring systems.
Also Read: Buying a House with Solar Panels Already Installed: Things to Know
6 Best Solar Charge Controllers
Well, after learning about the best PWM solar charge controller and ways to choose one, here is a list of the best charge controllers including MPPT charge controllers.
1. Binen Solar Charge Controller
This one is among the best solar charge controllers and is the most cost-effective. Binen Solar Charge Controller comes with an inbuilt display which is a plus on its price tag. Also, its maximum current rating is 30A so keep your expectations high for some good performance. It supports 12V and 24V solar panels, plus you get inbuilt USB ports. However, it is not backed with a warranty period, but it is acceptable at its price.
Also See: 13 Best Grid Tie Inverter with Battery Backup
2. Mohoo Solar Charge Controller
This one is also a budget-friendly option for you, but Mohoo Solar Charge Controller has a high maximum current rating of about 30A and this makes it a value-for-money charge controller. Though it does not feature an inbuilt display and has average build quality, it is compatible with 12V and 24V solar panels. Additionally, you can use its USB ports for charging your mobile. Despite being a budget-friendly option, it is not backed by any warranty, but this does not count as its cons because the charge controller performs well.
3. PowMr Solar Charge Controller
It is a budget-friendly option here but with its price range, it is a good choice. PowMr Solar Charge Controller is among the best solar charge controllers and has an inbuilt LED backlight and 20A maximum current rating. 12V and 24V solar panels are compatible with this controller, and it also has inbuilt USB ports that can be used to charge small devices, like your smartphone. However, it is backed with a 1-year warranty but being less pricey it’s build quality is average in comparison to other expensive charge controllers.
Note: We clearly do not promote the purchasing of expensive products. The information provided here is solely based on consumer reviews and not the website.
Also Read: 5 Best Generator for Off Grid Battery Charging
4. Rich Solar Charge Controller
It is one of the best charge controller options available based on its performance and affordable price tag. Though Rich Solar Charge Controller does not have remote monitoring, still you get an excellent maximum current rating of 40A. Also, you can keep your expectations high because it is compatible with 12V and 24 solar panels. Plus, it is backed with a 2-year-long warranty besides being a reliable charge controller.
Also See: 8 Best 3000 Watt Inverter
5. Epever Solarepic MPPT Solar Charge Controller
If you are looking for some high-performance controllers, then Epever Solarepic MPPT charge controllers can be considered. Though it is a bit expensive, it also is the most powerful option. For easy monitoring, connect this charge controller to your computer/laptop with an included cable. It supports 12V and 24V solar panels, offering you high flexibility along with a high-end 2-year long warranty. With its great build quality, keep your expectations high for this charge controller to last longer than its warranty period.
6. Victron Energy SmartSolar MPPT Solar Charge Controller
It is one of the best charge controllers in the market, known for its high reliability along with other features. Bluetooth connectivity and a maximum current rating of 30A make it an efficient option too. Further, this current rating is combined with a voltage rating of 12V or 24V, allowing you to use the Victron Energy SmartSolar charge controller with almost any solar panel. The most attractive feature of this MPPT charge controller is its 3-year warranty.
Well, now you know about the 5 best PWM solar charge controllers and their specifications. Do you already have one of the ones mentioned above? We would like to hear about your reviews of it. Also, we would recommend you share this informative article about the best charge controller with some potential solar customers.
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