Siemens SIMODRIVE 611A, Installation And Planning Manual

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9
02.98
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Siemens AG 1998 All Rights reserved 6SN1197–0AA00 02.98 Edition
SIMODRIVE 611 (PJ)
Comment
The line contactor in the NE module is used when the drives of the machine and
system are isolated from the supply when a fault condition occurs. In this case,
the power DC link is isolated from the supply. Inthis case, the electronics power
supply in the NE module always remains connected to the line supply. All exter-
nally wired bypass connections from the supply to the power DC link must also
be electrically isolated (p. 1-145 "Sequence and procedure...").
In the setting–up mode, when using an isolating transformer, the isolating trans-
former secondary may not be grounded. The grounding bar on the NE module
is used to ground the DC link M rail through 100 k
Ω
.
When using an auto–transformer in the setting–up mode, the user must monitor
the DC link voltage, and if a fault occurs, which results in an increase in the DC
link voltage, all drives of the machine and system must be isolated from the sup-
ply.
In the setting–up mode, when a hanging axis drops, it is possible, that the motor
can feed power into the DC link, even with the pulses inhibited, and thus in-
crease the DC link voltage.
When changing over from standard– to setting–operation, the DC link first re-
mains at 600 V. The voltage difference between 600 V and the rectified voltage
in setting–up operation represents a residual level of energy, which must be
considered on a case for case basis. A fault analysis must always be executed
before using the start inhibit function.
9.5.8 Comment