Satellite Antenna Gear Test System

This test system was designed to be used on the largest satellite tracking system in South Africa. The system controls three tests on the elevation and traverse gearboxes in situ. The three tests are to measure the backlash, the starting torque and the stiffness of the gearboxes.
The motor and gearbox test system comprises of a Motor and attached Shaft Encoder, a Motor Test System Interface Unit, a Power Supply and PC (including keyboard, screen and mouse) with two additional interface cards.

Functions and Tests that are Available:

• Manual PC control and display of all parameters.
• Backlash test.
• Starting torque test.
• Stiffness test.
• Return to the operating system.

Manual PC Control and Display of all Parameters
The motor current and voltage is displayed on the screen and the user can vary the motor current and voltage as desired. The shaft encoder counter values are also displayed with a reset button to zero them both. The shaft encoder direction is also shown and the user can also select the shaft encoder multiplier x1, x2, x3 or x4. The shaft encoder reference will also be indicated when the shaft encoder is in the reference position. Using the polarity reversal contactors the motor can be run either clockwise or anticlockwise. The output can be switched on or off and the power supply output can also be short circuited when both contactors are closed. The status of the auto/manual switch is also indicated. Both the spare relays can be controlled manually and their status indicated. The motor current and voltage are shown on the screen along with the raw voltages on all eight analog inputs.

Torsional Stiffness and Backlash Test
To do this test the gearbox output is locked. The operator then selects the maximum torque, the torque increments and the number of times the test is to be repeated. The results are shown graphically in different colours. The backlash is calculated from an average of the measurements obtained. The torsional stiffness is calculated from the slope of the curve and both measurements are displayed on the screen and saved to disk along with the test data for later analysis.

Starting Torque Test
In this test the gearbox output must be free. The operator can select the maximum torque allowable and the torque and time increments to be used. A graphical display of the torque versus time is displayed. The starting torque is then calculated and displayed on the screen, the measurements are displayed on the screen and saved to disk for later analysis.

Gear tooth height vs Bullgear Angle

This test system was developed from the Rooikat motor and gearbox test system which Danntech developed in the early 1980’s. The system can do various “in situ” measurements to establish the condition of any motor and gearbox drive system.

In the case of the Hartebeeshoek station the system was used to do tests to help evaluate the mechanical work required to refurbish a mechanical drive system to predict the improvement in performance that can be expected. After the refurbishment the tests were carried out again and the new performance specifications measured.

For any more information please contact us at:
Mike Dann
Danntech cc
P O Box 1023
Fontainebleau
Randburg
+27 11 792 1239
+27 82 900 0575