Identifying Unmarked Leads of a Y Connected Motor By: Augie Hand
Equipment: Test Light or ohmmeter, 6 or 12 volt battery, low scale voltmeter and numbered lead labels.
The motor should be assembled. The rotor is needed to complete the magnetic path. When a downscale deflection of the voltmeter needle
- 1. The 9 lead Y connected motor will have four circuits. Three of the circuits will have 2 leads and one circuit will have 3 leads. Identify the three sets of two and the one set of three using the test light or ohmmeter. Label the set of 3: 7,8, and 9.
- 2. To locate leads 1&4, Flash 8&9 as illustrated. Leads 1&4 will show little or no deflection and leads 3&6 and 2&5 will show strong deflections.
- 3. To identify 1 and 4: Connect the + terminal of the battery to 7. The–battery terminal will be flashed to 8. Connect the voltmeter to 1&4. With an upscale deflection, the + lead of the voltmeter will be on 1 and the–lead of the voltmeter will be on
- 4. 1&4 can now be labeled. Leads 3&6 can now be located. 3&6 will show little or no deflection. 2&5 will show strong deflection. 4. To identify 3 and 6: Connect the voltmeter leads to 3&6. Connect the–battery terminal to 7 and flash the + terminal to 9. With an upscale reading, the + lead of the voltmeter will be on 3 and the–voltmeter lead will be on 6. They can now be labeled. Connect the voltmeter leads to 2&5, connect the–battery terminal to 9. Flash 8 with the + battery terminal. With an upscale deflection, the + voltmeter lead will be on 2 and the–voltmeter lead will be on 5.