Are AC Adapters interchangable?

When trying to see if a charger or power supply will work with a device, you have to consider the output of the charger / supply *AND* the Input of the device to be charged / powered.

To explain a bit further, an AC charger / power supply / wall wart needs to be used for devices whose input is labeled "AC" and a DC charger for those devices that require *DC* input. The polarity of the DC current / voltage is important to match also, while those devices that use AC are usually not an issue no matter what 'polarity' is presented.

Voltage should match exactly or at least be within about a 5% - 10% higher tolerance range for safety of the device and persons operating it. No exceptions if you value the device and your safety. I give this tolerance as a percentage because having a half volt more on a 18 V device is acceptable, using a half a volt more at 1.5 V to 3 V is risky business for the device. Lower voltages will simply not work for most devices.

Current must also be considered. It should match exactly or be higher. In the case where it is higher, it should be said that this will only apply to devices in good working order as any faulty or weak component will be more likely to dramatically fail with higher current rated inputs. If it works correctly, the resistance of the circuit will limit the current draw at the correct voltage and prevent unwanted drama. If a component's resistance characteristics have gone out of bounds, then even the correct current / voltage / original power supply may destroy it and make it non-functioning in short order. It will simply fail more quickly and more dramatically if the current supplied is higher.

Some wall warts won't be suitable to power certain types of devices due to other factors such as line ripple filtration, duty cycle or induced hum. These will be discovered as you try them and should do no actual harm to the device, it either will or won't work as intended. No permanent damage will ensue if the power source is not repeatedly used long term in cases where it becomes an annoyance rather than just not working at all.

So, match the charger / supply / wall wart as closely as possible, use common sense and you should be all right.

I hope this will help you sort out your inventory to your advantage. Good luck!

That may depend on the miliamp rating of the adapter.

If an device requires 1000 miliamp from an adapter and you use an 750 miliamp adapter - it will work but not properly, I found that out on my MyFi -- the charge couldn't keep up with usage.