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  4. FAQ

General

  • 1. What is the Power Functions System?

    LEGO® Power Functions is the new LEGO electric building system. You have battery boxes to deliver the power, different types of motors to make things move, light, remote control and even connection to a computer. Everything fits together in a system to let you build and control your own inventions. To learn more about Power Functions, click here

  • 2. How is the Power Functions system different from the 9V system?

    The Power Functions system has 4 wires instead of the 2 wires in the 9V System. This gives a range of new possibilities that were not available before. Remote control functions, sensors, and intelligent control can now be used directly within the Power Functions system. Power is distributed from one Battery Box to Power Functions elements that are chained together in whatever combination you like.

  • 3. Can I use Power Functions elements with my old 9V elements?

    Yes, with 8886 Power Functions Extension Wire or 8871 Power Functions Extension Wire 20 you can use most of the 9V elements with Power Functions.

  • 4. Which frequency does the Power Functions IR Remote Control transmit at?

    The Power Functions IR Remote Control does not run on any frequency but on infrared (IR) technology. The IR Remote Control sends infrared light messages to the IR Receiver much like a television remote sends a signal to a TV.

  • 5. What do I do if my Power Functions model is not running?

    Follow these steps:
    1. Make sure there are fresh batteries in the Battery Box and the IR Remote Control. 
    2. Make sure all plugs are properly connected. 
    3. Make sure the green light on the Battery Box is ON. 
    4. Make sure the green light on the IR Receiver is ON. 
    5. Make sure there is connection between IR Remote Control and IR Receiver. 
    6. Make sure motors are not blocked.

  • 6. Why is my Power Functions model running slow?

    There can be 3 reasons for this:
    1. Make sure that all gearing from the attached Power Functions Motor to the moving parts is running smooth by turning it with your hands without the motor connected. If the parts are pressed too hard together or jammed in other ways the gears may not be able to turn freely.
    2. Make sure the batteries in the Power Functions Battery Box are fresh or fully charged.
    3. If you have too many motors running at the same time it will trigger the overload protection of the system. As a rule of thumb, you can drive 2 Power Functions XL-Motors, 3 Power Functions Train Motors or 4 Power Functions M-Motors at the same time from one Power Functions Battery Box. The XL-Motor requires about twice as much power as the M-Motor.

  • 7. Why does my Power Functions model drive backward when I want it to run forward?

    You can change the direction your model runs by flipping the small black switches located on each side of the channel selector of your IR Remote Control.

  • 8. What happens when the Power Functions overload protection kicks in?

    Overload protection is activated when too much power is consumed from either a Power Functions Battery Box or the IR Receiver. This can happen when a motor is blocked or when too many motors are running at the same time. If overload protection is activated, the Battery Box or the IR Receiver will cut off power to the output until power consumption has dropped under the allowed value. To regain power, unblock the motor or disconnect motors from the output – then turn the Battery Box OFF and ON again. Under overload protection, the green light on the Power Functions Battery Box will still be ON.

  • 9. What does the Power Functions Control Switch do?

    The 8869 Power Functions Control Switch included in 8293 Power Functions Motor Set allows you to control the direction that motors will turn and to turn lights ON and OFF. With the small black switch you can flip the direction of control.

  • 10. Can I use Power Functions with the MINDSTORMS NXT?

    Yes. With 8886 Power Functions Extension Wire or 8871 Power Functions Extension Wire 20 and the MINDSTORMS 8528 - NXT Converter Cable you can incorporate Power Functions elements with the NXT.

Remote Control

  • 1. How do I check the connection between the IR Remote Control and IR Receiver?

    How do I check the connection between the IR Remote Control and IR Receiver? 

    Follow these steps: 

    1. Connect the IR Receiver to the Battery Box. Turn on the Battery Box and check that the green next to the channel selector on the IR Receiver is ON.  
    2. Check that the green light in the black eye of the IR Remote Control turns on when you push one of the control buttons or turn a dial. If not, make sure the IR Remote Control has fresh batteries. 
    3. Make sure that IR Remote Control and IR Receiver are set to the same channel . 
    4. Now point the IR Remote Control at the IR Receiver and push one of the control buttons or turn a dial. The light on the IR Receiver will now flicker to indicate reception. 
    5. Please note that the distance between IR Remote Control and IR Receiver, room size, direction and angle used when holding the IR Remote Control, IR Receiver direction, and ambient light are all factors that will affect control distance.

  • 2. How do I test the Power Functions IR Remote Control to make sure it is working?

    Test your Remote Control by following these steps:

     

    1. Connect a Power Functions IR Receiver to the plug of the Power Functions Battery Box 
    2. Turn the Battery Box ON . The green light on the Battery Box should light up. 
    3. The green light next to the channel selector on the IR Receiver should be ON. 
    4. Make sure you have fresh batteries in the Power Functions IR Remote Control. 
    5. Select the same channel on the IR Remote Control and IR Receiver. 
    6. Push any button or turn a dial on the IR Remote Control and the green light on the black eye of the IR Remote Control will light up. Also, the green light on the IR Receiver will flicker to indicate that the signal is being received. 
    7.  Connect a Power Functions Motor on each plug of the IR Receiver. 
    8. On the IR Remote Control push the control button or turn the dial with the red mark. The motor connected on the output with the red mark will now turn. 
    9.  On the IR Remote Control push the control button or turn the dial with the blue mark. The motor connected on the output with the blue mark will now turn. 
    10. Use the small black switches on the IR Remote Control to flip the direction of control for that output.

  • 3. How many channels does the Power Functions IR System have?

    The Power Functions IR System has 4 channels. On the Power Functions IR Remote Control and IR Receiver you have a channel selector switch. The selected channel must be the same on both IR Remote Control and IR Receiver to have control. All 4 channels can be active at the same time. To play 4 at the same time each IR Remote Control and IR Receiver will need to select a different channel.

    Another way of using the channels is to control more functions with one IR Remote Control. For example, you can have 4 IR Receivers in one model set to different channels and then use the channel selector on the IR Remote Control to select which functions are being controlled. In this way one IR Remote Control can control 8 individual functions.

  • 4. What is the reaching distance of the Power Functions IR Remote Control?

    Under normal conditions reaching distance will exceed 10 meters or roughly 33 feet. Bright sunlight, low batteries in the IR Remote Control or blocking of the line of sight all can decrease reaching distance.

  • 5. What is the IR Receiver V2?

    The IR Receiver V2 has an improved motor driver giving you lower power loss and longer battery lifetime.
    Currently, the IR Receiver V2 is only available in the 9398 4x4 Crawler.
    The IR Receiver V2 can be recognized by a V2-print added on the front.

  • 6. What are the small black switches on the Power Functions IR Remote Control used for?

    The direction of control can be reversed using the small black switches on the Power Functions IR Remote Controls.

Batteries

  • 1. What type of batteries is needed for the Power Functions system?

    The following batteries are used in Power Functions:

    AA Batteries:
    8881 Power Functions AA Battery Box uses 6 AA batteries

    AAA Batteries:
    88000 Power Functions AAA Battery Box uses 6 AAA batteries
    8885 Power Functions IR Remote Control uses 3 AAA batteries
    8879 Power Functions IR Speed Remote Control uses 3 AAA batteries

    It is important to change all batteries at the same time being sure not to mix old and new ones. Use Alkaline batteries.

    For a good rechargeable solution we suggest 8878 Power Functions Rechargeable Battery Box. This rechargeable battery box has the exact same size as the Power Functions AAA Battery Box and they can be interchanged directly

  • 2 What is the battery lifetime for the Power Functions system elements

    In general battery lifetime will strongly depend on use.
    In heavy loaded models with more XL Motors and M Motors (e.g. the 8275; Motorized Bulldozer) you will have around 4 hours drive time with the 8881 Power Functions AA Battery Box.

    The 88000 Power Functions AAA Battery Box is used for less demanding tasks. With a Train Motor or 2 M Motors the drive time will be around 4 hours.

    For a good rechargeable solution we suggest 8878 Power Functions Rechargeable Battery Box. This rechargeable battery box has the exact same size as the 88000 Power Functions AAA Battery Box and they can be interchanged directly.

  • 3 Can I use rechargeable batteries in the Power Functions Battery Box and IR Remote Control

    Yes. Even though the voltage of rechargeable batteries is a bit lower, it is possible to use them. However, the speed of motors may not be as high as when using alkaline batteries.
    For a good rechargeable solution we suggest 8878 Power Functions Rechargeable Battery Box . This rechargeable battery box has the exact same size as the 88000 Power Functions AAA Battery Box and they can be interchanged directly.

  • 4 How do I change the batteries in the Power Functions Battery Box

    It is important to change all batteries at the same time being sure not to mix old and new ones. Use Alkaline batteries.

    Power Functions AA Battery Box 
    This box holds 6 AA batteries. The Power Functions AA Battery Box has lids on each side. Each compartment holds 3 AA batteries. To open the lid, hold both thumbs on the lid and push it off in the direction of the arrows. Then insert the batteries and close again. Remember to replace the batteries in both sides!


    Power Functions AAA Battery Box
    This box holds 6 AAA batteries. Unfit the 2 screws and remove the bottom casing. Insert 6 fresh AAA batteries following the instructions in the inserts.

    It is not possible to change batteries of the 8878 Power Functions Rechargeable Battery Box, but as a good rechargeable solution we suggest this product. This rechargeable battery box has the exact same size as the 88000 Power Functions AAA Battery Box and they can be interchanged directly.

  • 5 How do I change the batteries in the Power Functions IR Remote Control

    Both the 8885 Power Functions IR Remote Control and 8879 Power Functions IR Speed Remote Control uses 3 AAA batteries. You will need a small screwdriver to loosen the screw on the backside. Take off the lid and then insert the batteries. Put the cover back on and screw it in place.

  • 6 What indicates that the batteries are flat on my Power Functions Battery Box or IR Remote Control

    As the batteries are used in the Battery Box attached motors will run slower. When the motors are no longer performing well it is time to change the batteries.

    When the reaching distance of the IR Remote Control decreases it is time to change batteries.

  • 7 Why does my Power Functions model only run for a short period after I change the batteries

    Follow these guidelines to get the maximum life from your batteries: 
    1. 1. Make sure all 6 batteries are changed with fresh batteries. 
    2. Use Alkaline, Lithium or rechargeable batteries. 
    3. Remember to turn off the Power Functions Battery Box OFF when not being used to save battery power. 

    For a good rechargeable solution we suggest 8878 Power Functions Rechargeable Battery Box . This rechargeable battery box has the exact same size as the Power Functions AAA Battery Box and they can be interchanged directly.

Motors

  • 1 What type of batteries is needed for the Power Functions system

    As a rule of thumb, you can drive 2 Power Functions XL-Motors, 3 Power Functions Train Motors or 4 Power Functions M-Motors at the same time from one Power Functions Battery Box. If you wish to run a combination of motors, you can e.g. have 1 XL and 2 M running together. The XL-Motor requires about twice as much power as the M-Motor. The Battery Boxes and the IR Receiver have overload protection, so attempting to drive too many motors will not damage anything. The power a motor consumes depends on what function the motor is performing. Motors will operate best when driving a small load.

  • 2 Is it possible to control the speed of the Motors

    Yes. The speed can be controlled on the following motors: 8883 Medium Motor
    Large Motor (not available at LEGO.com until March 2013)
    8882 XL Motor
    88002 Train Motor

    The speed can be controlled by the following elements:
    8879 Power Functions IR Speed Remote Control is used for controlling the speed at 7 levels in both directions.
    8878 Rechargeable Battery Box is used for controlling the speed at 7 levels in both directions.

  • 3 How do I test Battery Boxes and Motors in the Power Functions system to make sure they are working

    Test your Battery Box and Motors by following these steps:

    1. Make sure there are fresh batteries in the Power Functions Battery Box  
    2. Turn ON the Power Functions Battery Box. The green light will light up to indicate it is turned ON. The Battery Box should always be turned OFF when not in use to conserve battery power. 
    3. Connect a Power Functions M, XL or Train Motor to the plug of the Battery Box. 
    4. Use the orange switch/dial on the Battery Box to make the motor run. 
    5. Turn OFF the Power Functions Battery Box to make the motor stop.
    6. Repeat steps 3-6 with all motors to make sure they work. 
    7. Stack plugs of more motors on top of each other and connect them to the plug on the Power Functions Battery Box. All attached motors will now drive in the same direction when the orange switch/dial is operated.

  • 4 How is it possible to see that the output on the Servo Motor is positioned correctly

    Right above and below the output there are two sets of black dots. If these dots are vertical aligned the Servo Motor is positioned correctly, and you can start building your model.
    If they are not aligned you can you can use one of the following elements to center position the output:

    • 8869 Control Switch (Push the Control switch to center) 
    • 88000 AAA Battery Box (Push the Control switch to center) 
    • 8878 Rechargeable Battery Box (Turn the speed control dial to the middle position) 
    • 8879 IR Speed Remote Control (hit the STOP button or use the jog wheel) 
    • 8885 IR Remote Control (Push and release the control button)