Operation with e.l.c.bs – Lenze Inverter EMC User Manual
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Operation with e.l.c.bs
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EDBEMV EN 1.3
10
Operation with e.l.c.bs (earth-leakage circuit breakers)
Danger!
The controllers are internally equipped with a mains rectifier. In the event of a
short-circuit to frame, an earth leakage current can block the tripping of
AC-sensitive and / or pulse-current sensitive e.l.c.b. and thus cancel the protective
function for all equipment operated on this e.l.c.b..
Different protection measures are suitable to protect humans and animals (DIN VDE 0100).
Note the following when using earth-leakage circuit breakers:
z
Pulse-current sensitive e.l.c.bs in systems with controllers with single phase mains
connection (L1/N)
z
Universal-current sensitive e.l.c.bs in systems with controllers with three-phase mains
connection (L1/L2/L3)
z
E.l.c.bs must only be installed between mains supply and controller.
E.l.c.bs can be activated although not wanted by
z
Capacitive leakage currents of the cable shields during operation (especially with long,
shielded motor cables),
z
Mains connection of several controllers at the same time,
z
Use of additional RFI filters.
The intensity of these capacitive earth currents depends on the following factors:
z
1AC- or 3AC frequency inverter, phase failure
z
Inverter-internal EMC elements
z
Length and type of motor cable
z
Mains voltage level
z
Switching frequency level
z
Winding structure in the motor
z
Installed filters on the mains / motor side
z
Mains switch make and break characteristics
Remedies
z
Low-capacitance and short motor cables
z
Increase switching frequency (e.g. 16 kHz)
z
Switch mains phases simultaneously (e.g. contactor)
z
Provide supply via isolating transformer
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