Eaton EMS2 SWD Series, Руководство пользователя

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4 Short-circuit / motor protection
4.2 Motor protection
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EMS2…-SWD Electronic motor starter 10/19 MN120008EN www.eaton.com
4.2.1 Symmetry detection
The motor currents are measured at phases L1 and L3 and monitored for
symmetry.
If the motor currents deviate by more than ≥ 33 %, the motor shuts down
within 2 minutes.
If the motor currents deviate by more than ≥ 67 %, (e.g., phase failure),
the motor shuts down within 2 seconds.
The deviation can be calculated using the following formulas.
|I
max
| > I
nenn
→ deviation = (I
max
- I
min
)/I
max
|I
max
| < I
nenn
→ deviation = (I
max
- I
min
)/I
nenn
4.2.2 Motor with brake
If a motor with brake (connection in the motor terminal board) is connected,
the 400 V AC brake must be linked to the 2/T1 and 6/T3 terminals.
A 230 V AC brake must be connected to the 4/T2 terminals and the star point
of the motor.
￫
In the event of high clock rates, the motor protection function
may trip due to the increased switch-on currents
WARNING
Increase motor current monitoring to the nominal brake current.
This should be set accordingly on the hybrid motor starter.