If it is still awful, the inserts themselves will occasionally get burnt marks in them, causing a slight brief. Usually, if it’s open, it is infinite or well above 2K ohms.Ĭable and Plug Note Oftentimes, the connector onto the cable to the engine will get coolant in it. If you read zero, a brief between phases exists.
Place meter on ohms: T1 to T2 T2 to T3 T1 to T3 The scope generally expected is.3 to 2.0 ohms, although most are all about. Testing For Open & Short In Motor Winding. Just beware that from 230 meg to 600 meg frequently shows some deterioration in the cables or engine insulation. The above is exactly what I found to be typical for 230 Vac 3 Phase Motors.Įven though 230 meg for a 230 Vac circuit appears on the low side from my experience.
It can give false and unrepeatable readings causing one to pursue your narrative. Most shorts will be below 20 megohms.īe careful not to touch the wires to anything when taking the reading. Readings are often in a variety from 600-2000 Megohms. Ensure that you use a quality meter moving up to 10megohms.Īssess all 3 wires separately T1, T2, T3 (three phases) to the ground cable. Many servo motor shorts may be read with a normal quality meter. If it goes directly to the motor and disconnect from the cable and checks the motor and the cable individually.īe sure to be certain leads on both ends are not touching anything including the other leads. If it’s zero or reads some continuity at all, then a problem is present with the motor or cable. Check all three wires singly T1, T2, T3 (three phases) to the ground wire. Testing For Short For Ground With Ohm Meter.ģ phase motor winding resistance values, Using Ohm meter: Disconnect all power from the system.