All motors must be designed for running at 12 VDC though they will actually be run with a PWM signal at 24 VDC.
Permanent magnet motors are preferred as needing less power.
Brush type motors are preferred as less expensive.
All grade 1 motors draw less than 1.50 amps at 12 VDC
All grade 2 motors draw less than 3.00 amps at 12 VDC
All grade 3 motors draw less than 5.00 amps at 12 VDC
All motors shall be reversible by reversing the current to the motor either with a computer or with a DPDT switch/relay.
The limit on motor torque is the power that can be transmitted by a screw tightened onto the 0.157 inch diameter shafts of the Meccano system. Extra torque can be destructive in our system. An 5 amp motor at 12 VDC is pretty much too powerful for Meccano but can proved a large torque at low speeds when controlled with an appropriate PWM (Pulse Width Modulated) signal. Thus the grade 3 designation does make some limited sense.
Motor shaft specifications
0.1575 inch diameter by 5/8 inch long
Shafts must be hardened to take set screws without deforming
A flat on the motor shaft is optional but is recommended on grade 2 and 3 motors.
All motor shafts must be at the 1/2 inch spacing module
when the motor is mounted on its plate.
Screw post or solder connections may be used on motors.
Provisions should be made to allow one switch to be mounted on the motor mounting plate so that it is handy at the motor.
Stepper motors are desireable but need special controllers. I have not addressed the fact that there need to be two types of controllers, one for the standard DC motors and one for the stepper motors. The level 2 controller is currently designated for stepper control. (Ingnoring servo motors for now).
These are too expensive for present considersation but their prices keep falling so they will be viable soon.
Servo motor with encoders and full computer control.
Very desireable but too expensive for now
Motor Shaft Adapter should not be needed on motors that meet the of specifications
All motors provided must have 0.158 inch shafts. Of course other motors may be used and it is most desireable that these motors have 0.158 inch shafts adapters and appropriate mounting plate.
09 Apr 04