ELECTRICAL MACHINE TEST BENCH Lucas Nuelle Electrical Machines Test Bench

Lucas Nuelle Electrical Machines Test Bench is a bench-mounting unit. It works with other optional instruments to give a full range of tests on the optional range of fractional horsepower (FH) machines. The test bench gives a d.c. supply and variable resistances to adjust the current in the field coils and armatures of d.c. machines. It also has a fixed a.c. supply for the a.c. machines, single and three-phase. The user presses large push-buttons to stop and start the power supplies. The test bench includes a three-phase rotor-starting resistance arrangement for the optional Wound Rotor Induction Motor. Included on the test bed is a fixed d.c. machine that works as a dynamometer to load the shafts of the other machines. The test bench energises the dynamometer and measures the torque and speed of its shaft.

Students use these measurements to find the torque and power delivered by the machine under test. The user operates a control on the front of the test bench to vary the torque (load). They can also select an external input control for use with the optional Data Management System for computer-controlled load tests. The test bench has two meters: one shows the torque, the other shows the speed. Sockets under the meters output speed and torque signals and accept the external torque control signal. The test machines fit into a sliding cradle on either side of the dynamometer. Most machines fit into the right-hand cradle. The left-hand cradle is mainly for the D.C. Compound Motor because it can work as a generator, a synchronous motor and a prime mover. This cradle is also for machines when they work as an extra inertial load to the test machine. A clear guard covers the coupling between the machine under test and the dynamometer. The nylon coupling allows for slight mechanical misalignment between the test

machine and the dynamometer. The test bench includes a taper pin to lock the rotor of selected test machines for ‘locked rotor’ tests. Supplied with each optional test machine is a plate with a mimic diagram of the machine’s windings. The plate fits over a set of sockets on the front of the test bed. Students can easily see how to connect the supplies to the test machine. For more enquiries about this training equipment, contact me on my Contact page at www.aglotechami.com