Charge laptops in green Middle School mobile cart

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Why don't the laptops in the green cart get fully charged?

In response to a report that the green laptop cart was not charging computers effectively, I made two changes and one discovery that should help you get the laptops fully charged for the start of each class period. This leads to the following tip, which Lynda has very kindly taped to the top of the cart.

When you return laptops to the green mobile cart, flip the black power switch on the side of the cart to "off” then immediately back to "internal.” Confirm that the orange or green lights on the computer power adapters are lit, indicating that they now have access to power.

See the following diagram for the location of the black switch (circled in red).

Here is the full explanation. The problem was that the cart was only charging half of the laptops at a time. I rewired the power adapters so that the computers are all on the same circuit within the cart, so that they should all now charge at the same time. The discovery was that the cart has an internal timer that causes it to alternate the halves of the cart that are being charged. In order to prevent the cart from charging the side that is now unused, I lengthened the time interval to 100 minutes and discovered that you can reset the timer by flipping the cart power on and off.