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How do LEGO® Power Functions work?

  • 88000 AAA Battery box

    The battery box is the starting point of any LEGO Power Functions (LPF) construction, which delivers power to drive the functions. The battery box has the LPF female plug, which contains the 4 connections of the LPF system: 2 for power supply and 2 for control.

    The power supply of the LPF system runs unbroken throughout your entire construction, where the female plugs are the feeding plugs. This means that from any female plug you have direct connection to the power. So it works similar to the power supply of an extension cord in your house.

    This battery box holds 6 AAA batteries. To get the best result you should use alkaline or rechargeable batteries.

    To change the batteries, you must unscrew the two screws underneath and remove the cover. You will now be able to see the batteries. Now, replace all 6 AAA batteries (3 on each side) with fresh ones.

    Battery lifetime will depend heavily on the way it is used and on the quality of the batteries. The AAA Battery box delivers up to 800 mA current. You can drive 2 XL Motors or 4 Medium motors together. If you exceed the maximum current the overload protection will kick in. You should then disconnect everything from the box and turn it off for a while before turning the power back on again.
    To turn the battery box ON, press the green button. The green indicator LED will now be lid. To turn the battery box OFF, press the green button again. If you leave the battery box ON, it will automatically turn OFF after 2 hours.

    If you press and hold down the green button for more than 3 seconds the green light will blink to indicate that auto turn OFF is disabled. This means that a motor will run until the batteries are empty. To enable again turn the AAA Battery Box OFF and ON again.

    You can connect any combination of LPF elements to the plug and then use the Control switch to operate the function connected.

    The AAA Battery box has tube building interface underneath and studs at the top. The size and building interface exactly the same as the Rechargeable Battery Box. The size is 4 x 8 x 4 modules.

  • 88002 Train Motor

    The Train motor is made to fit the LEGO train track system. The speed fits best with the small LEGO train wheels – using the bigger wheels is not recommended. The Train motor delivers a maximum torque of 8,1 mNm (450 mA). Without load its rotation speed is around 1830 rotations per minute.
    The current consumption will depend heavily on the load it is driving. Under normal conditions it can be around 225 mA and we do not recommend a continuous use above 450 mA.
    If the motor is blocked the current will exceed the maximum limit of the LPF system. Turn the Power OFF, unblock the motor and turn Power ON again.
    The Train motor snaps under a plate hole and will pivot around the snap as the train drives through curves in the track.

  • 88003 L-Motor

    This is the Large Motor. It delivers a maximum torque of 45,4 mNm (450 mA). Without load its rotation speed is around 380 rotations per minute.

    The current consumption will depend heavily on the load it is driving. Under normal conditions it can be around 225 mA and we do not recommend a continuous use above 450 mA.

    The Large Motor fits within 3 modules in width and height at the front, and has an overall length of 7 modules. At the body of the motor the height is 4 modules. With snap interface on both the front, back, and on the sides, it is easy to fit and lock into TECHNICS constructions.

  • 88004 Servo Motor

    This is the Servo Motor. With this Motor you are able to build models such as vehicles with a true steering of the wheels. Just like the steering of a real car. The Servo Motor fits within 3 modules in width, 5 modules in height and 7 modules in length. With snap interface on both the front and on the sides it is easy to fit and lock into TECHNICS constructions.

    The Servo Motor has front and back outputs which are linked together. This makes it easier to build four-wheel steering. The output can, from its center position (vertical), turn up to 90 degrees clockwise and counter-clockwise with 7 steps in each direction. In total you have 15 positions:

    • 1 center position
    • 7 positions clockwise
    • 7 positions counter-clockwise

    When the Servo Motor is controlled with full power in either direction it will turn to the full 90 degrees position (for example with the IR Remote Control).

    When it is controlled with power steps in either direction it will turn through the 7 positions corresponding to the 7 power levels (for example with the IR Speed Remote Control or the Rechargeable Battery Box).

    The Servo Motor delivers a maximum torque of 250 mNm (300 mA). Without load it rotates with 360 degrees per second. This corresponds to the output turning from center to horizontal position in 0,25 seconds.

    The current consumption will depend heavily on the load it is driving. Under normal conditions it can be around 150 mA and it should never exceed 300 mA.

    When you start building your model it is important that the output is center positioned – this is indicated when the 4 dots at the output are aligned. To set the Servo in center position, connect it to an output with power ON but no control (for example on an IR Receiver that is turned ON).

  • 8869 Direct Control Control Switch

    With the Control Switch you can build your own control into your LEGO model.

    If you connect motors and/or lights to the output plug you can use the orange Control switch to turn these ON or OFF.

    With the Direction switch you can flip the direction of control.

  • 8870 Light

    In this Light unit we have 2 bright white LED’s. Each LED is placed inside a transparent housing with a tube that fits inside a TECHNIC hole.
    Both the lights will turn ON together when control is active in either direction.
    You can use the lights together with colored transparent LEGO bricks to create different light effects. It works better with some colors than with others.
    The lights consume very little current – you can drive several hundred light units at the same time.

  • 8871 Extension Wire 50cm

    If the length of the wiring on the elements is getting too short you can use the Extension Wires. They come in lengths of 20cm and 50cm.

    Notice that the Extension Wire has only 1 LPF male plug and 2 LPF female plugs.
    To keep a bridge to the LEGO 9V Electric system we have a 9V plug at one end of the wire (it is the LPF control line that is wired out). In this way you are able to use most of your 9V elements with the LPF system.

  • 8878 Rechargeable Battery box

    This is the Rechargeable Battery box. It holds a Lithium Polymer battery pack with storage capacity of 1150 mAH. The output voltage is 7,4 V.

    To charge the battery you should use the 10 VDC LEGO Transformer. While you are charging the red indicator LED will blink. When charging is done it will be constant ON. While the Transformer is connected you can power models for constant drive. You connect any combination of LPF elements to the plug.

    Press the green button to turn the battery box ON - the green indicator LED will be lid. After 2 hours the battery box will auto turn OFF (only when transformer is not connected).
    The Rechargeable battery box has a dial for power control on the output. The power of a motor can be controlled in 7 steps in either direction. In the middle position the motor will not rotate.

    The Rechargeable battery box delivers up to 800 mA current. You can drive 2 XL Motors or 4 Medium motors together. If you exceed the maximum current the overload protection will kick in. You should then disconnect everything from the box and you will need to start charging before you can turn the battery ON again.

    The Rechargeable Battery box has tube building interface underneath and studs at the top. The size and building interface exactly the same as the AAA Battery Box.
    The size is 4 x 8 x 4 modules.

  • 8879 Remote control IR Speed Remote Control

    Before using the IR Speed Remote Control you must insert 3 AAA batteries (use alkaline or rechargeable). To do this you will need to unfit the screw on the backside and open the battery compartment.

    Select the IR Channel with the selector switch and remember to set the IR Receiver on the same channel.
    This IR Speed Remote Control is for power control and has 2 control buttons – Red and Blue. These correspond to the outputs on the IR Receiver. By turning the jog wheel in either direction it will for each click increase or decrease the power of a motor on the corresponding output of the IR Receiver. Power can be controlled in 7 steps. The IR Receiver will keep on driving at the selected power until a new command is received. Hitting the red STOP button will brake the motor.
    If the direction of the power control is not logic in the model you can flip the direction of control by using the direction switches. When you use the control buttons the green LED will flicker to indicate transmission – if it does not it is time to change batteries. When you change batteries make sure to replace all at the same time, and not mixing old with new ones. The reason is that a flat battery will leak or can get hot when mixed with new ones.

    Using the building interface you can snap more IR Speed Remote Controls together or build your own joystick or jog wheel control.

  • 8881 AA Battery Box

    The battery box is the starting point of any LEGO Power Functions (LPF) construction, which delivers power to drive the functions. The battery box has the LPF female plug, which contains the 4 connections of the LPF system: 2 for power supply and 2 for control.

    The power supply of the LPF system runs unbroken throughout your entire construction, where the female plugs are the feeding plugs. This means that from any female plug you have direct connection to the power. So it works similar to the power supply of an extension cord in your house.

    This battery box holds 6 AA batteries. To get the best result you should use alkaline or rechargeable batteries. When you change batteries remember to replace all 6 with new fresh ones.
    To change batteries, take off one lid on each side and insert 3 AA batteries in each side.

    Battery lifetime will depend heavily on the way it is used and on the quality of the batteries. This battery box delivers up to 800mA. You can drive 2 XL Motors or 4 Medium motors together. If you exceed the maximum current, the overload protection will kick in.

    You should then disconnect everything from the box and turn it off for a while before turning the power back on again.
    You can connect any combination of LPF elements to the plug and then you use the Control switch to operate the function. In the middle position power is OFF. By pushing the switch in either direction you turn power ON and control the function in either direction. When power is ON, the green indicator LED will light up.

    This battery box has LEGO TECHNIC building interface and the size is 4 x 11 x 7 modules.

  • 8882 XL Motor

    This is the XL Motor. It delivers a maximum torque of 90,4 mNm (600 mA). Without load its rotation speed is around 220 rotations per minute.

    The current consumption will depend heavily on the load it is driving. Under normal conditions it can be around 300 mA and we do not recommend a continuous use above 600 mA.
    If the motor is blocked the current will exceed the maximum limit of the LPF system. Turn the Power OFF, unblock the motor and turn Power ON again.

    The XL motor fits within 5 modules both in width and height and with the snap interface in the front and on the sides it is easy to fit and lock into TECHNIC constructions.

  • 8883 Medium Motor

    This is the Medium Motor. It delivers a maximum torque of 40 mNm (300 mA). Without load its rotation speed is around 380 rotations per minute.

    The current consumption will depend heavily on the load it is driving. Under normal conditions it can be around 150 mA and we do not recommend a continuous use above 300 mA.
    If the motor is blocked the current can exceed the maximum limit of the LPF system. Turn the Power OFF, unblock the motor and turn Power ON again.

    The Medium motor fits within 3 modules both in width and height and with the snap interface in the front it is easy to fit into TECHNIC constructions. At the bottom side it has tube interface for System construction.

  • 8884 Remote Control IR Receiver

    To power up the IR Receiver you connect the input plug to an LPF female plug (e.g. on a Battery box). When power is ON the green LED beside the channel selector will light up.

    The IR Receiver V2 version 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 has 2 output plugs – Red and Blue. On each plug you can connect one or more function elements that you want to control.
    Now you need an IR Remote Control. Make sure they are set to the same channel. On the IR Remote Control you will have controls corresponding to the Red and the Blue output. The green LED will flicker to indicate that a valid control signal is received. Now you are in direct control of the actions connected to the IR Receiver.

    When we designed the IR Receiver we tried to imagine all the ways of remote control that could be interesting now and in the future. All this functionality is already build into the IR Receiver.

  • 8885 Remote control IR Remote Control

    Before using the IR Remote Control you must insert 3 AAA batteries (use alkaline or rechargeable). To do this you will need to unfit the screw on the backside and open the battery compartment.

    Select the IR Channel with the selector switch and remember to set the IR Receiver on the same channel.
    This IR Remote Control is for direct control and has 2 control buttons – Red and Blue. These correspond to the outputs on the IR Receiver. Pushing a control button forward will drive a motor on the corresponding output of the IR Receiver full power in one direction.
    Pushing it backwards makes it drive in the other direction. When you release the control button it will return to center position and the motor will turn OFF.
    If the direction of control is not logic in the model you can flip the direction of control by using the direction switches. When you use the control buttons the green LED will flicker to indicate transmission – if it does not it is time to change batteries. When you change batteries make sure to replace all at the same time, and not mixing old with new ones. The reason is that a flat battery will leak or can get hot when mixed with new ones.

    Using the building interface you can snap more IR Remote Controls together or build your own control interface.

  • 8886 Extension Wire 20cm

    If the length of the wiring on the elements is getting too short you can use the Extension Wires. They come in lengths of 20cm and 50cm.

    Notice that the Extension Wire has only 1 LPF male plug and 2 LPF female plugs.
    To keep a bridge to the LEGO 9V Electric system we have a 9V plug at one end of the wire (it is the LPF control line that is wired out). In this way you are able to use most of your 9V elements with the LPF system.

  • RC Remote Control

    With the LEGO Power Functions IR system you can build your own remote controlled LEGO models. It could be a car, a train, a robot or even a device to turn on and off the lights of your room.

    The IR Remote Control and the IR Receiver work together: You do the control on the IR Remote Control and it sends IR signals to the IR Receiver.

    In the LEGO Power Functions IR system we have 4 channels. The IR Receiver and – Controller must be set to the same channel to make the control link work. With the 4 channels you can either have 4 different models controlled at the same time with 4 individual controllers or you can use the channel selector as a function switch on one IR Remote Controller to access 4 different IR Receivers in the same model setup controlling up to 8 individual functions.
    To keep a bridge to the LEGO 9V Electric system we have a 9V plug at one end of the wire (it is the LPF control line that is wired out). In this way you are able to use most of your 9V elements with the LPF system. The reaching distance of the Remote Control will depend on many things – under normal conditions it will exceed 10m. The following things will reduce reaching distance:
    • Bright sunlight
    • Low batteries in the IR Remote Control
    • Blocking of the line of sight