USB charger noise and temperature

[Android Central Question]

My charger from nesux 5 is whining when its plugged but gets quiet when its connected to the phone and charging. As soon as I remove the cable from my phone it starts whining again. Also it gets pretty hot, probably around 110-120F.
Is this normal? Can I keep using it?

 

[SpookDroid]

It is not normal that it heats up that much. It is normal for some faint buzzing sound depending on how well your AC source is kept at a constant and appropriate level (i.e. if it oscillates too much or falls below a certain threshold, then that's not well balanced) since the internals of the charger that go from the AC power source to the DC one supplied to the phone are doing their thing and some energy is lost there. BUT if it's getting too hot, either the charger is faulty or your power line is really not good enough.

When you connect it to the phone, some of that energy is transferred from the charger to the phone itself, thus balancing some of the excess energy causing the whirring. Again, if it gets too hot, I'd rather just change the charger if you're certain your power line is OK.

 

[Kodak2]

If your charger is getting hot when not connected to the phone then that is a fire hazard. As above, bin it and get a replacement to be on the safe side.