Recently LEGO Education upgraded its NXT Batter Pack and Power Charger from AC to DC. It is important to note that both battery packs and chargers will work on all versions of the LEGO MINDSTORMS NXT robotics system. The change simply makes current and future sets more energy efficient.
If you are uncertain which battery pack and power charger you have with your materials, here are some helpful hints:
1. The new DC battery is white. The AC version is dark grey.
2. The new DC battery has 10V DC is embossed in the lower right corner of the battery. The AC version has 9-12V embossed on the lower left corner.
3. The cord to the new DC power supply will be positioned to the side when plugged into a standard outlet. The AC power supply cord is positions under the prongs when plugged into a standard outlet.
If you have any questions about the changes or need further assistance identifying between the DC and AC battery packs and power charges, please contact your local LEGO Education Consultant.