4 Electrical Installation
4.1 General Requirements
WARNING
EQUIPMENT HAZARD
Rotating shafts and electrical equipment can be
hazardous. It is important to protect against electrical
hazards when applying power to the unit. All electrical
work must conform to national and local electrical codes.
Installation, start up, and maintenance must be
performed only by trained and qualified personnel.
Failure to follow these guidelines could result in death or
serious injury.
WARNING
WIRING ISOLATION
Run input power, motor wiring, and control wiring in 3
separate metallic conduits, or use separated shielded
cable for high frequency noise isolation. Failure to isolate
power, motor, and control wiring could result in less than
optimum frequency converter and associated equipment
performance.
Run motor cables from multiple frequency converters
separately. Induced voltage from output motor cables
run together can charge equipment capacitors even with
the equipment turned off and locked out. Failure to run
output motor cables separately or use shielded cables
could result in death or serious injury.
•
Run output motor cables separately.
•
Use shielded cables.
•
Lock out all the frequency converters simulta-
neously.
Wire type and ratings
•
All wiring must comply with local and national
regulations regarding cross-section and ambient
temperature requirements.
•
Danfoss recommends that all power connections
are made with a minimum 75
°
C (167
°
F) rated
copper wire.
•
See
for recommended
wire sizes.
WARNING
SHOCK HAZARD
The frequency converter can cause a DC current in the
PE conductor and hence result in death or serious injury.
•
When a residual current-operated protective
device (RCD) is used for protection against
electrical shock, only an RCD of Type B is
allowed on the supply side.
Failure to follow the recommendation means that the
RCD cannot provide the intended protection.
Overcurrent protection
•
Extra protective equipment such as short-circuit
protection or motor thermal protection between
frequency converter and motor is required for
applications with multiple motors.
•
Input fusing is required to provide protection
against short circuit and overcurrent. If fuses are
not factory-supplied, the installer must provide
them. See maximum fuse ratings in
.
4.2 EMC-compliant Installation
To obtain an EMC-compliant installation, follow the
instructions provided in
chapter 4.5 Mains, Motor, and Ground Connections
, and
.
4.3 Grounding Requirements
WARNING
GROUNDING HAZARD
For operator safety, a certified electrical installer should
ground the frequency converter in accordance with
national and local electrical codes and instructions
contained within this manual. Ground currents are higher
than 3.5 mA. Failure to ground the frequency converter
properly could result in death or serious injury.
•
Proper protective grounding for equipment with
ground currents higher than 3.5 mA must be
established.
•
A dedicated ground wire is required for input
power, motor power, and control wiring.
•
Use the clamps provided with the equipment for
proper ground connections.
•
Do not ground 1 frequency converter to another
in a daisy chain fashion (see
).
Electrical Installation
Quick Guide
MG06A702
Danfoss A/S © 03/2017 All rights reserved.
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