Power Functions components [image by © LEGO]
In 2007 LEGO published a new standardised electric power system for all kind of LEGO models. Power Functions was born. One of the first sets with Power Functions was the Technic Bulldozer #8275.
For this modular system now different components are available. Most of them also could be used for LEGO trains.
I use Power Functions in different train engines and for the LL 6950 Rocket Transport.
As of autumn 2018, Power Functions will gradually be replaced by the successor system Powerd Up. The transition takes place again fluently since 2019 also Technic sets appear with Power Functions.
Power Functions – Power/Batteries [image by © LEGO]
Power Functions – Power/Batteries
The power for Power Functions is carryied on board by using batteries or rechargeable batteries:
- Lithium-ion rechargeable battery #8878
- Battery box for 6 AA-batteries #8881
- Battery box for 6 AAA-batteries #88000
The rechargeable battery #8878 or the AAA-battery-box #88000 can be integrated into a train engine or waggon.
They are 8 studs long, 4 studs wide and 4 rows of bricks high. On top you need some space to attach the cable which leads to the receiver.
To load your rechargeable battery you need a Transformer 10V DC #8887 (or a similar device). The turning knop can control the speed of a motor which is attached directly to the battery. If the receiver #8884 is used, the speed can only be controlled using the remote control.
Power Functions – Cable [image by © LEGO]
Power Functions – Cable
All Power Function components have a fixed attached cable. The cable has 4 wires, the outer ones carry constant currency, the inner ones are for control purposes, e.g. to set the speed.
At the bottom of the connection plates of the extension cables #8886 (20 cm) and #8871 (50 cm) you will find connections which fits to your old 9 V electric system. So use these cables if you want to combine components from both worlds.
The polarity switch #8869 is a useful extra. It is required if two motors are attached to the reciever at the same time but you want the motors to turn in different directions.
Power Functions – Receiver [image by © LEGO]
Power Functions – Receiver
To remote control your Power Function models an IR receiver #8884 is necessary. This component is attached between the battery and the motor or the lighting. It receives the signals which are send out by the remote control.
The receiver has to channels, e.g. for separate controls of drive motors and lighting. The upper, round part should not be covered by any other elements, otherwise the receiver can not receive signals.
Power Functions – Remote Control [image by © LEGO]
Power Functions – Remote Control
Use the remote controls #8885 and #8879 to control your Power Function models. Use the orange knops or wheels to change the direction or the speed. You can also select the channel you want to send your informations – but make sure the same channel is set at the receiver. The remote controls need two AAA batteries which will last very long.
The simple remote #8885 allows a simple forward-stop-backwards but no permanent drive. It is more useful for vehicles (steering and drive) or for winches.
During a Power Functions workshop when LEGO invited some fans to Denmark we raised the wish for another remote control which allows to controll speed and keeps the motors running while not holding the knops of the remote device. That is how the #8879 speed remote control was born.
Power Functions – Lighting [image by © LEGO]
Power Functions – Lighting
Use the light set #8870 to bring some light into the darkness. Each set has two little LED lights which could be attached to any hole where a stud or Technic axle will fit in. The major problem is to tidy up all the cable mess while integrating this light unit into a small model like a steam engine.
Power Functions – Motors [image by © LEGO]
Power Functions – Motors
There are three universal Power Functions motors #8883 (M-Motor), #8882 (XL-Motor) and a mid-sized #88003 (L-Motor) available. Also a Power Function train motor #88002 is available. All of them have a fixed attached cable which is attached to the receiver or the battery box directly.
The Technic set #9398 and others includes a #88003 servo motor for steering functionality.
Power Functions train motor
#88002 [image by © LEGO]
Power Functions – Train Motor
The Power Functions train motor #88002 draws power from batteries which are carried on the train.
A Power Functions cable is permanently installed in the motor. The wheels used are standard size train wheels with a Technic cross hole. A Technic axle with a length of 6 is used as the axle.
This motor was only available in black, the side panels (with recesses for the Technic axle) in black and light gray.
The external dimensions of the Power Functions train motors and the 9 V train motor are identical.
Further information
The two French guys Philo and Didier Enjary present further, much more technical information about electric LEGO components at their website:
- Power Function motors: www.philohome.com/pf/pf.htm.
- Other LEGO motors: www.philohome.com/motors/motorcomp.htm.
- LEGO train motors: www.philohome.com/ttrain/ttrain.htm.