Tools required:

  • Multimeter

 

 

1

Please remember to unplug the machine 

 

Follow the appropriate guide for your machine to disassemble the cover panels.

 

NOTE: You do not need to remove the main control board to measure the motor windings. 

 

 

 

2

Locate the large 6 pin motor connector on the motor side.

 

 

 

 

 

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3

The motor winding has 3 pairs of phases.

 

The power controlled by software on the Main Control Board which determines the direction (positive or negative) and voltage (size of force) which is sent through each of the coils. The sequence of power flow is what makes the motor rotate.

 

 

 

 

 

4

To measure the motor winding resistance:

 

Please select one of the 3 phases and probe the multimeter across the 2 terminals. Repeat for all 3 pairs

 

Set the multimeter to measure resistance (in ohms). The corresponding resistance measurements are below.

 

 

Machine

Correct Motor Winding Resistance

Nova DVR XP, Saturn, Galaxi, Orion, Nebula Lathes

 

Nova Voyager, Vulcan Drill Press

 

9 – 11 ohm

Nova Viking drill press

1.7 – 2 ohm

Nova Neptune, Neptune Max Lathe

6.8 – 7.5 ohm

 

 

 

 

 

 

5

To check motor winding insulation

 

 

Sometimes, the insulation on the copper windings used to construct the motor may be broken, this will result in power leakage through to the motor headstock which may result in a shock or the machine will trip the fuse.    

 

To check if the insulation has broken on the motor windings, set one probe of the multimeter on an exposed metal part of the motor windings (Do not use painted areas), the other probe should be on 1 of the three phases.

 

 

 

 

 

 

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Set the multimeter on continuity mode or resistance mode and check if any of the 3 phases is shorting to the main casting. Repeat for all 3 phases.

 

IF any of the 3 phases is shorting out to the motor body then the insulation on the motor windings has broken. The headstock can no long be used.