Cardiff E.T.T. Motor Testing Software

Quality Assurance Test Unit.

This project consists of software for testing electric motors at the end of a production line. All types of motors for fans, small traction, and fractional horse-power motors are catered for, with the exception of complex multiphase motors. Up to three phases are tested, with the details being displayed on the screen before printing out and recording. All the interfaces with the hardware are constructed in a 'failsafe' manner.
Here is a view showing part of a Test Screen:-

Acknowledgement: Woods Industrial Fans
(N.B. The screen test messages here are for illustrative purposes only).

Equipment settings for each motor are taken from the manufacturer's database file (a different set of values for each of several hundreds of motor-types).
These settings are applied automatically via the hardware.

The electrical resistance of each coil is measured and compared with the ideal, or 'target' value held on file. If the value is within the acceptable tolerance the PASS condition is indicated on the screen (as are the associated measurement details). Then the reactance of each winding is measured and displayed. Each type of motor has its preferred test voltage for this, to allow for current build-up in the coil. Where appropriate, the winding direction is assessed and displayed. Insulation resistance is determined, using the test voltage given in the Specifications File. The ability to withstand high voltage is determined in the Flash Test, between all the motor windings. There are 10mA and 20mA trip levels for this, and a one second duration.

The perspex safety cover on the motor test bed must be closed before any high voltages can be applied.
New types of motor can be introduced by the customer, simply typed into the networked Specification File.