Monday, January 15, 2018

Lego Power Function Motors ⚡️⚙️

What are they?

Lego Power Function Motors are the small electric motors that Lego currently manufactures.  They are small motors that can be powered by Lego battery boxes, or an older Lego 9 Volt Train Controller. The motors can run in either direction, and drive an axle socket.  So any lego piece with the cross shaped axle connector can be inserted into the motor.
(left) XL Motor (right) M Motor

These Lego PF motors come in a few sizes: Medium, Large, Extra Large and Servo.
Servo Motors behaves differently then the other motors, as they were designed for adding steering to a radio controlled car, and only have 180 degrees of rotation.  Maico Arts has some instructions for modules with Servo motors here

The regular motors that rotate 360 have different speed and torque ratings as follows:

Approximate Values
M Motor - 40 nMn Torque, 380 RPM
L Motor - 45 mNm Torque, 380 RPM
XL Motor - 90 mNm Torque, 220 RPM

How do they work?

Like most Lego and Technics, the PF Motors have various connection points which include technic pin holes, and additionally on the M Motor there are anti-studs so you can stick the motor directly to bricks. (I do this in my Greylime module)

When connected to a battery box the motor will run at full speed in either direction.  When connected to a 9 volt Train Controller you can vary the speed in 6 increments.

Determining what speed you can run your motor at is one of the first key elements you need to decide upon before you start constructing your modules.  If you don't have access to a train controller you can attain different speeds by building gearboxes and linkages. (To be discussed in another article)

A Lego M Motor connected to a battery box via a Control Switch
A Lego M Motor connected to a 9 Volt Train Controller using an extension cable.

Motors can drive all sorts of mechanisms with some creative building.  Watch a few GBC layout videos you'll see how these motors can be used.

Video: My simple layout with 4 different lift mechanisms.

Where can you get them?

Lego Online and Retail Stores - Look for the 8293 Power Functions Motor Set

Individual Purchase on Lego Shop @ Home: Extras → Power Functions

On BrickLink search for the following parts:
Power Functions M Motor: 58120c01
Power Functions L Motor: 99499c01
Power Functions XL Motor: 58121c01