Danger And Warning Notices; Checking The Insulation Resistance - Siemens HT-direct Operating Instructions Manual

Three-phase synchronous motor

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Commissioning

4.2 Danger and warning notices

4.2

Danger and warning notices

Dangerous voltage at the motor terminals when the rotor is rotating

There is always a magnetic flux in the motor due to the permanent magnets in the rotor.

With each rotation of the rotor, a voltage occurs at the motor terminals. As a result of this,

there is also a voltage at the converter output terminals via the connecting cable. When

working on the drive system, you must prevent any rotational movement of the motor shaft.

Dangerous voltage via the converter

As long as the feeding converter is switched on, or the DC link of the converter is not

discharged, there can be a voltage at the motor terminals even when the rotor is not

moving. Depending on the type of converter, the voltage can be up to 1,000 V. Ensure that

the five safety rules are complied with before working on the motor:

1. Isolate

2. Protect against reconnection

3. Make sure that the equipment is de-energized

4. Ground and short-circuit

5. Cover or enclose adjacent components which are still live

[ID 800.01]

4.3

Instructions relevant to safety

Dangerous, high voltages

During and immediately after measurement, dangerous voltages are sometimes present at

the terminals. Do not touch the terminals.

If the supply feeder cables are connected, you must ensure that the line voltage cannot be

connected. Once you have measured the insulation resistance, discharge the winding by

connecting the ground potential.

WARNING

A5E01083943A AB

Siemens AG Operating Instructions 2.02 1FW4

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