Dan converts regular pianos into player pianos for a living. He wants to know how he can make sure he isn't drawing too much amperage or wattage and damage the power device. How can he prevent that? Leo says that in general, a power brick won't work if it doesn't match the wattage. Leo says that watts are volts times amps. So watts are where he'll want to be careful. So take the volts and multiple by amps, and see what voltage it can take. Both should be on the power supply or adapter.
Scott got an Anker backup battery and sometimes he gets a warning that the accessory may not be supported, and it stops charging the phone. It even does it with the Apple charging block. Rich says that Apple has a program called Apple MFI (made for iPhone). If his accessory is MFI, then the culprit could be a failing cable. It could also be that his phone's connector could have some lint in it preventing his cable from connecting completely. Rich suggests taking a toothpick and sweeping it out. A gentle burst of canned air is a good idea too, but he should be sure to be gentle.