3 Installation
3.8 Insulation testing
DA1 Variable Frequency Drives
08/18 MN04020005Z-EN
www.eaton.com
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3.8 Insulation testing
The variable frequency drive of the DA1 series are tested, delivered and
require no additional testing.
If insulation testing is required in the power circuit of the PDS, you must
consider the following measures.
Testing the motor cable insulation
▶
Disconnect the motor cable from the connection terminals U, V and W of
the variable frequency drive and from the motor (U, V, W).
Measure the insulation resistance of the motor cable between the
individual phase conductors and between each phase conductor and the
protective conductor.
The insulation resistance must be greater than 1 M
Ω
.
Testing the mains cable insulation
▶
Disconnect the mains cable from the power supply network and from
connection terminals L1/L, L2/N and L3 of the variable frequency drive.
Measure the insulation resistance of the mains cable between the
individual phase conductors and between each phase conductor and the
protective conductor.
The insulation resistance must be greater than 1 M
Ω
.
Testing the motor insulation
▶
Separate the motor cable from the motor (U, V, W) and open the bridge
circuit (star or delta) in the motor terminal box.
Measure the insulation resistance of the individual motor windings.
The measurement voltage must at least match the rated operating
voltage of the motor but is not to exceed 1000 V.
The insulation resistance must be greater than 1 M
Ω
.
CAUTION
No leakage resistance tests are to be performed with an
insulation tester on the control signal and the connection
terminals of the variable frequency drive.
CAUTION
Wait at least 5 minutes after switching the supply voltage off
before you disconnect one of the connection terminals
(L1/L, L2/N, L3, DC-, DC+, BR) of the variable frequency drive.
￫
Consider the notes from the motor manufacturer in testing the
insulation resistance.
