TESTING

The goal is to test the long-term performance of three different slip-rings for use in a magnetic measurement system. A coil of wire is rotated through a magnetic field in order to induce a small voltage. This voltage is measured through the slip-rings in its raw and integrated forms periodically over the duration of the test. Integration of the raw coil voltage gives the magnetic flux independent of time. Readings will be taken at a variety of rotational speeds to see how the slip-rings perform under various conditions. In between readings, the slip-rings will be rotated at 600 rpm, their maximum allowable speed.

 Below is an outline of the testing procedure. Click here for the detailed testing procedure.

 Test Sequence 

1. Start of test: Immediately take initial coil voltage readings according to steps a-d in Procedure for Taking a Set of Readings (see below). Shaft starts from rest and is accelerated to 600 rpm in order to perform the first measurement.

2. After the reading at 30 rpm is completed, the system will accelerate back to 600 rpm. Readings will be taken every 10,000 revolutions.

3. When the appropriate number of revolutions between readings has elapsed, the system will begin to take the set of readings according to steps a-d in Procedure for Taking a Set of Readings.
4. When the 30 rpm reading is completed, return to step 2.

Procedure for Taking a Set of Readings 

1. Use proportional control to maintain motor speed.
2. When the desired speed is attained, take measurement coil voltage readings (integrated and raw) at the following speeds:

3. Each set of readings will be stored in a text file on the local computer running the LabVIEW software. The text file will also include the total number of elapsed revolutions at the beginning and end of the measurement period, the date, and the time the measurement period began.