August 19, 2014

Fudging It: What Happens if You Use the Wrong Adapter?

Fudging It: What Happens if You Use the Wrong Adapter?

computer on fireIdeally, you’ll have the same voltage, current and polarity on your adapter and device.

But what if you accidentally (or purposefully) use the wrong adapter? In some cases, the plug won’t fit. But there are many cases where an incompatible power adapter will plug into your device. Here’s what you can expect in each scenario:

  • 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, then 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, may be fine, but it just won’t get as loud. More complex devices will falter, and may even shut themselves off when they detect an undervoltage condition. Usually, an undervoltage 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, then it may run hotter than normal, which can shorten the life of the device or cause immediate damage.
  • Current too high – If the adapter has the correct voltage, but the current is higher than what the device input requires, then 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 simply 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 voltage to drop (see voltage too low above). For laptops running on undercurrent adapters, you might see the battery charge, but the laptop not powering on, or it may run from power but the battery won’t charge. Bottom-line: it’s not a good idea to use a lower current rating adapter, since it could cause excess heat.


August 05, 2014

How to find a replacement adapter by matching stats

Your replacement adapter much match these 5 criteria:

1) OUTPUT Volts (V)

2) Amps or milliamps (A or mA)**

3) OUTPUT Current (AC or DC)

4) Tip size***

5) Tip polarity (+ or -). To find tip polarity there is usually a diagram on the adapter that looks like this (+)---- •)-----(-) The line that touches the dot in the middle, in this example its positive, is the polarity of the tip (polarity of the inside of the tip, outside of the tip would be negative.

Be sure your looking at the Output stats.   For all the adapters I sell, you can disregard the matching of Input if you are in the United States.   Some countries will require 220V.   Some of the adapters I sell are rated to 220V and could be used with a converter as the wall sockets are shaped different. 


It is important you match all 5 of these criteria or you could underpower your device, causing certain function not to work correctly, if at all.   You could also damage your device, ruin the battery pack, create a fire hazard or pop a breaker.  The only flexible criteria from the list above is the amps.  A device will only use as much amps as it needs and no more.  You need to match the amp rating or have MORE amps. If the device needs 300mA, i.e., you can match 300mA or more (400ma and up).


**Milliamps to amps: 1000mA is = 1A (i.e. 1200mA is 1.2A and 300mA is 0.3A)

***Tips are measured in millimeters (mm) for an inner diameter and outer diameter of the circles on the ends of the tip. Alot of adapters are 5.5mm (outer circle) x 2.5mm (inner circle).


NOTE:  Not even if you match all the criteria is the adapter guaranteed to work as there are different kinds of current flow, switching adapters, etc etc that is too hard to explain in layman's terms.

Of course the best way to replace an adapter is my finding the model number of the adapter you need that goes to your specific device. It might be in the owner's manual, near the plug in to your device, on the box,  or you can call the manufacture to find out.