Installation requirements:
The overall electrical safety of the frequency converter requires special installation
considerations regarding:
• Fuses and circuit breakers for over-current and short-circuit protection
• Selection of power cables (mains, motor, brake, loadsharing and relay)
• Grid configuration (IT,TN, grounded leg, etc.)
• Safety of low-voltage ports (PELV conditions).
Consult the relevant clauses in these instructions and in the VLT
®
AQUA Drive Design Guide
for information about the installation requirements.
2.1.5. Caution
The frequency converter's DC link capacitors remain charged after power has been
disconnected. To avoid an electrical shock hazard, disconnect the frequency con-
verter from the mains before carrying out maintenance. Wait at least as follows
before doing service on the frequency converter:
Voltage Min. Waiting Time
15 min. 20 min.
380 - 480 V 110 - 450 kW
525 - 690 V 132 - 630 kW
Be aware that there may be high voltage on the DC link even when the LEDs are turned off.
2.1.6. Avoid unintended Start
While the frequency converter is connected to mains, the motor can be started/stop-
ped using digital commands, bus commands, references or via the Local Control
Panel.
• Disconnect the frequency converter from mains whenever personal safety considerations
make it necessary to avoid unintended start.
• To avoid unintended start, always activate the [OFF] key before changing parameters.
• Unless terminal 37 is turned off, an electronic fault, temporary overload, a fault in the
mains supply, or lost motor connection may cause a stopped motor to start.
2.1.7. Safe Stop Installation
To carry out an installation of a Catego-
ry 0 Stop (EN60204) in conformity with
Safety Category 3 (EN954-1), follow
these instructions:
1. The bridge (jumper) between Termi-
nal 37 and 24 V DC must be re-
moved. Cutting or breaking the
jumper is not sufficient. Remove it
entirely to avoid short-circuiting. See
jumper on illustration.
2. Connect terminal 37 to 24 V DC by a
short-circuit protected cable. The 24
V DC voltage supply must be inter-
ruptible by an EN954-1 Category 3
circuit interrupt device. If the inter-
rupt device and the frequency con-
verter are placed in the same instal-
lation panel, you can use an
unscreened cable instead of a
screened one.
VLT AQUA High Power Operation Instructions 2. Safety
MG.20.P1.02 - VLT
®
is a registered Danfoss trademark
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