Will 9v 1000mA power adapter work with your 9v 300mA device?

Answer 1

Yes you can, however in an unusual situation (i.e. electrical fault in the device), the adapter will allow 5x the current the device is rated for to pass into that device. In normal operation, the device will draw what it needs, based on fans running or not, etc. Under these conditions, as long as the adapter puts out the proper Voltage, the device will operate just fine.

Answer 2

Yes, the device will only use the mA it needs.

In theory it should but it totally damaged my Digital Blood Pressure monitor and it's LCD went mad immediately after I tried to connect a higher mA adapter to it.

One should also keep in mind the 'polarity' ie plus and minus terminals on the adapter as they should match the one specified for the equipment otherwise that equipment would get damaged.

I think, just think, that adapters with higher mA (same voltage) do not work like a car battery but transmit a fixed amount of mA which is specified on the adapter. Thus when you use a 700mA adapter on a 300 mA device it will damge the device because the adapter would give out 700mA continuously ( and unlike a car battery won't increase it's mA gradually?}

Better not to use a high powered ( ie mA) instead of a low powered adapter...there is every chance that the gadget will get damaged, more so if it is of the digital type. Polarity also matters.

Answer 3

No it will not work. The output of the adapter is high enough but the voltage difference is too high. The adapter must have an output of 12 volts and any amperage over 500 ma or .5 amps will do the job.

Answer 4

Yes! It will work well because your device needed only 300mA, but the adapter can afford until 500mA.

Answer 5

No, both the voltages do not match and the device draws more current than the adapter can supply.