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Installation
Honeywell
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4.2.7 Cable and motor insulation checks
These checks can be performed as follows if motor or cable insulations are suspect-
ed to be faulty.
1. Motor cable insulation checks
Disconnect the motor cable from terminals U/T1, V/T2 and W/T3 of the frequency
converter and from the motor. Measure the insulation resistance of the motor cable
between each phase conductor as well as between each phase conductor and the
protective ground conductor.
The insulation resistance must be >1MOhm.
2. Mains cable insulation checks
Disconnect the mains cable from terminals L1, L2/N and L3 of the frequency convert-
er and from the mains. Measure the insulation resistance of the mains cable between
each phase conductor as well as between each phase conductor and the protective
ground conductor.The insulation resistance must be >1MOhm.
3. Motor insulation checks
Disconnect the motor cable from the motor and open the bridging connections in the
motor connection box. Measure the insulation resistance of each motor winding. The
measurement voltage must equal at least the motor nominal voltage but not exceed
1000 V. The insulation resistance must be >1MOhm.
