Oftentimes, we find ourselves looking for substitutes for our technical devices in certain situations. Which is why most laptop users tend to use laptop chargers of a lower wattage power adapter. Although this seems like a nice hack for a while, there might be a few consequences of using a lower wattage charger for your laptop.
Also Read: How Many Watts Does It Take to Charge a Laptop?
What Does Charger Wattage Mean?
To put it simply, the wattage indicates the amount of power that can be drawn in once your laptop is connected to the power outlet. Each and every single charger has its own level of wattage, which is why they are categorized as either “high wattage chargers” or “low wattage chargers”.
How Exactly Does a Laptop Power Supply Work?
We can compare the power demanded by your laptop with the need for lighting in your room. Although you might be alright with dimmer lights or lights with lower brightness levels and power such as 45W or 60W bulbs, they won’t be as effective for when you need extremely bright light for work.
Also Read: Can I Leave My Laptop Plugged in Overnight?
Similarly, the supplied power supply of your laptop is built to handle and endure the worst possible charging conditions. And although it may seem to function normally in most cases, it won’t be getting enough power to run high capacity programs.
Once your charger has been plugged into the wall socket, the AC power is automatically converted into DC power and transmitted to the motherboard. The motherboard will then distribute it to various other parts of your laptop, especially the battery as it will be storing DC power that can be used later.
Can I use a Lower Wattage Charger for my Laptop?
The answer is yes. You definitely can use a lower wattage charger for your laptop [you can even charge your laptop without a charger!], but this will directly impact the performance of your laptop itself. For instance, using a 45 watt charger for a laptop that requires 90 watts might not enable it to function at its maximum potential. Again, this greatly depends on the type of activity being carried out on your laptop itself.
Also Read: Laptop Won’t Turn on OR Charge [FIXED]
For instance, if you’re using your laptop to read some article, or if your laptop stays idle with minimal brightness level, the low wattage charger will work perfectly fine. But if you plan on watching a video or a movie at high volume, it is highly likely that your laptop rejects the power coming in through the charger, and switches over to the DC power stored in its battery. Since the laptop will not be gaining any power through the low wattage charger, it will ultimately shut down once the battery runs out.
Also Read: Can You Use a Laptop Without a Battery?
Using a low wattage charger for your laptop will be more of a frustration, rather than a convenience to you. Based on multiple reviews and experiences by users, as well as professionals, it can become quite difficult to properly charge your laptop through a low wattage charger. Since the power trickles in slowly, it might take hours to fully charge your laptop, which is definitely not an ideal situation if you’re in a hurry.
What are the Risks Associated with Using a Low Wattage Charger for your Laptop?
With a low powerage, you can potentially cause a fuse in the power supply, damaging it and various other components of your laptop. Since your laptop will be charging at a slower rate than usual, despite having a high current, the battery of your laptop will get ruined as well. The life of your battery will be substantially reduced, and it will get drained at a much faster rate as well.
Also Read: How to Replace Laptop Battery Cells
Most users also complain about their device and the adapter overheating, since it takes a longer time for the battery to fill up. These cooling problems could also have some other negative impacts on your device, further reducing the performance and capability of your laptop.
There will also be the risk of breaking some components of your laptop as they will be demanding power, but will be unable to get it due to a power shortage resulting from using a lower wattage charger.
Also Read: Laptop Lags Slows Down When Plugged In Charging? [FIXED]
When you use a lower wattage charger, the voltage regulator inside of the motherboard adjusts the voltage in the current to match with the requirements of the internal components of your laptop. This way, you can easily power up your device with a lower wattage charger that has a minimal difference than the one actually required to power up your device. For instance, you can easily charge your 20V PC with a 19V charger without any complications.
But if the difference ends up being significantly higher, you might end up facing complications with the voltage regulator, so much so that it ends up failing or breaking down.
Is it Possible to use a Lower Wattage Charger Without Harming your Laptop?
Realistically, there is one situation where you could use a lower wattage charger without negatively impacting your device and its performance. If you plug in your laptop when the battery is fully charged for external power support, you can avoid both overheating your device as well as ruining the life of your battery.
In case the battery of your device is not charged, make sure that you’re not currently using the laptop while it charges. Doing so will further protect the life of both your laptop, as well as its battery.
Although it isn’t recommended to use a lower wattage charger for a substantially high powered device due to the complications that can occur from it, professionals have deemed it to be safe to use when in a sticky situation. Continuous usage of a lower wattage charger will, however, will be risking serious damage to your precious device.
You may also like:
How Many Watts Does It Take to Charge a Laptop?
Can I Leave My Laptop Plugged in Overnight?
Laptop Won’t Turn on OR Charge [FIXED]
Can You Use a Laptop Without a Battery?
How to Replace Laptop Battery Cells
Laptop Lags Slows Down When Plugged In Charging? [FIXED]
Wait! Just because the plug for that universal adapter fits into your laptop or phone doesn’t mean it’s safe to use. Read this guide on finding the right charger or power adapter.
The other weekend, I sat down and sorted through all my random electronics junk. As part of that process, I took all my power supplies and adapters and threw them into a box. It ended up being a pretty big box. I’m willing to bet that any given household has a dozen or more different types of cell phone chargers, AC/DC adapters, power bricks, power cables, and charger plugs.
Having so many chargers can be pretty frustrating. It’s easy to get them separated from the phone or laptop or tablet, or router. And once that happens, it can be complicated to figure out which goes with which. The default solution is to try random plugs until you find one that fits into your device. However, this is a big gamble. If you grab an incompatible power adapter, your best case scenario is that it works, albeit not the way the manufacturer intended. The second worst-case scenario is that you fry the gadget you are trying to power up. The worst-case scenario is that you burn down your house.
In this article, I’m going to walk you through the process of digging through your junk drawer and finding the right power adapter for your device. Then, I’ll tell you why it’s so important to do so.
A Very Brief Introduction to Electrical Terminology
Each AC/DC power adapter is specifically designed to accept a certain AC input [usually the standard output from a 120 V AC outlet in your home] and convert it to a particular DC output. Likewise, each electronic device is specifically designed to accept a certain DC input. The key is to match the DC output of the adapter to the DC input of your device. Determining the outputs and inputs of your adapters and devices is the hard part.
Power adapters are a bit like canned food. Some manufacturers put a lot of information on the label. Others put just a few details. And if there is no information on the label, proceed with extreme caution.
The most important details for you and your delicate electronics are the voltage and the current. Voltage is measured in volts [V], and current is measured in amps [A]. [You’ve probably also heard about resistance [Ω], but this doesn’t usually show up on power adapters.]
To understand what these three terms mean, it helps to think of electricity as water flowing through a pipe. In this analogy, the voltage would be the water pressure. Current, as the term implies, refers to the flow rate. And resistance relates to the size of the pipe. Tweaking any of these three variables increases or decreases the amount of electrical power sent to your device. It’s important because too little power means your device won’t charge or operate correctly. Too much power generates excess heat, which is the bane of sensitive electronics.
The other important term to know is polarity. There is a positive pole [+] and a negative pole [-]. For an adapter to work, the positive plug must mate with a negative receptacle or vice versa. By nature, direct current is a one-way street, and things won’t work if you try to go up the downspout.
If you multiply the voltage by the current, you get the wattage. But the number of watts alone won’t tell you if the adapter is right for your device.
Reading an AC/DC Adapter Label
If the manufacturer was smart enough [or compelled by law] to include the DC output on the label, you are in luck. Look at the “brick” part of the adapter for the word OUTPUT. Here, you’ll see the volts followed by the direct current symbol and then the current.
The DC symbol looks like this:
To check the polarity, look for a + or – sign next to the voltage. Or, look for a diagram showing the polarity. It will usually consist of three circles, with a plus or minus on either side and a solid circle or C in the middle. If the + sign is on the right, then the adapter has positive polarity:
If there is a – sign on the right, then it has negative polarity:
Next, you want to look at your device for the DC input. You’ll usually see at least the voltage near the DC plug receptacle. But you also want to make sure the current matches, too.
You might find both the voltage and the current elsewhere on the device, on the bottom or inside a battery compartment cover, or in the manual. Again, look for the polarity by either noting a + or – symbol or the polarity diagram.
Remember: the input of the device should be the same as the output of the adapter. This includes polarity. If the device has a DC input of +12V / 5.4A, get an adapter with a DC output of +12V / 5.4A. If you have a universal adapter, make sure it has the proper current rating and choose the correct voltage and polarity.
Fudging It: What Happens if You Use the Wrong Adapter?
But what if you accidentally [or purposefully] use the wrong adapter? In some cases, the plug won’t fit. But there are many instances where an incompatible power adapter will plug into your device. Here’s what you can expect in each scenario:
- The wrong polarity – If you reverse the polarity, a few things can happen. If you’re lucky, nothing will happen, and no damage will occur. If you are unlucky, your device will be damaged. There’s a middle ground, too. Some laptops and other devices include polarity protection, which is essentially a fuse that burns out if you use the wrong polarity. If this happens, you might hear a pop and see smoke. But the device may still work on battery power. However, your DC input will be toast. To fix this, either replace the polarity protection fuse or get it serviced. The good news is that the main circuitry wasn’t fried.
- Voltage too low – If the voltage on an adapter is lower than the device, but the current is the same, then the device may work, albeit erratically. If we think back to our analogy of voltage being water pressure, it would mean that the device has “low blood pressure.” The effect of low voltage depends on the complexity of the device. A speaker, for example, might be okay, but it won’t get as loud. More sophisticated devices will falter and may even shut themselves off when they detect an under-voltage condition. Usually, an under-voltage condition won’t cause damage or shorten the life of your device.
- Voltage too high – If the adapter has a higher voltage, but the current is the same, then the device will likely shut itself off when it detects an overvoltage. If it doesn’t, it may run hotter than normal, which can shorten the device’s life or cause immediate damage.
- Current too high – If the adapter has the correct voltage, but the current is greater than what the device input requires, you shouldn’t see any problems. For example, if you have a laptop that calls for a 19V / 5A DC input, but you use a 19V / 8A DC adapter, your laptop will still get the 19V voltage it requires, but it will only draw 5A of current. As far as current goes, the device calls the shots, and the adapter will have to do less work.
- Current too Low – If the adapter has the correct voltage, but the adapter’s rated current is lower than what the device input, then a few things might happen. The device could power on and draw more current from the adapter than it’s designed for. This could cause the adapter to overheat or fail. Or, the device may power on, but the adapter may not be able to keep up, causing the voltage to drop [see voltage too low above]. For laptops running on undercurrent adapters, you might see the battery charge, but the laptop is not powering on, or it may run on power, but the battery won’t charge. Bottom line: it’s a bad idea to use a lower current rating adapter since it could cause excess heat.
You would expect to see all of the above based on a simple understanding of polarity, voltage, and current. What these outlooks don’t take into account is the various protections and versatility of adapters and devices. Manufacturers may also build a bit of a cushion into their ratings. For example, your laptop may be rated for an 8A draw, but in reality, it only draws around 5A. Conversely, an adapter may be rated at 5A, but can withstand currents up to 8A. Also, some adapters and devices will have voltage and current switching or detecting features that will adjust the output/draw depending on what’s needed. And, as mentioned above, many devices will automatically shut down before it causes damage.
That being said, I don’t recommend fudging the margin under the assumption that you can do the equivalent of driving 5 MPH over the speed limit with your electronic devices. The margin is there for a reason, and the more complicated the device, the more potential for something to go wrong.
Have any cautionary tales about using the wrong AC/DC adapter? Warn us in the comments!
P.S. Wall adapters that give you a USB port for charging aren’t nearly as tricky. Standard USB devices have a 5 V dc voltage and a current up to .5 A or 500 mA for charging only. This is what allows them to play nice with the USB ports on your computer. Most USB wall adapters will be 5 V adapters and have a current rating well over .5 A. The iPhone USB wall adapter I’m holding in my hand right now is 5 V / 1 A. You also don’t have to worry about polarity with USB. A USB plug is a USB plug, and all you usually have to worry about is a form factor [e.g., micro, mini, or standard]. Furthermore, USB devices are smart enough to shut things down if something isn’t right. Hence, the oft-encountered “Charging is not supported with this accessory” message.
Feature image by Qurren – GFDL [//www.gnu.org/copyleft/fdl.html] or CC-BY-SA-3.0 [//creativecommons.org/licenses/by-sa/3.0/], via Wikimedia Commons
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