

The power management system also knows the electronic nameplate of the power supply and thus its rated power.

The loads are prioritized: the machine has priority over the battery charger. The power management must maintain the following inequality balanced, in terms of power: (power adapter + battery as a power source) >= (battery charger + the machine). The battery as a power source is exclusive of the battery charger: a battery may operate as a power source, or the battery charger may operate, but never both at once.

It will clearly run at full capacity for longer than a higher wattage adapter or even fail to keep up with the energy demands of a machine using more than 60w giving you a flat battery if you run a deficit of energy “while charging”. So no, a 60W adapter won't overheat when connected to a machine that needs an 85W adapter. This is a given for the systems to receive safety certifications. I will give some facts along with my reasoning.Īll MagSafe adapters, when plugged into a mechanically matching receptacle on a MacBook/MacBook Pro, are designed to run safely. There is a lot of misinformation in some answers.
