Danfoss VLT FC 103 Operating Instructions Manual page 29

Installation
For safety, comply with the following requirements:
•
Electronic controls equipment is connected to
hazardous mains voltage. Take extreme to protect
against electrical hazards when applying power
to the unit.
•
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.
•
Field wiring terminals are not intended to receive
a conductor one size larger.
Overload and equipment protection
•
An electronically activated function within the
frequency converter provides overload protection
for the motor. The overload calculates the level of
increase to activate timing for the trip (controller
output stop) function. The higher the current
draw, the quicker the trip response. The overload
provides Class 20 motor protection. See
chapter 9 Warnings and Alarms for details on the
trip function.
•
Because the motor wiring carries high frequency
current, it is important that wiring for mains,
motor power, and control are run separately. Use
metallic conduit or separated shielded wire. See
Illustration 3.24. Failure to isolate power, motor,
and control wiring could result in less than
optimum equipment performance.
•
All frequency converters must be provided with
short-circuit and overcurrent protection. Input
fusing is required to provide this protection, see
Illustration 3.25. If not factory supplied, fuses must
be provided by the installer as part of installation.
See maximum fuse ratings in
chapter 11.3.1 Protection.
MG16J202
Operating Instructions
Stop
Start
Speed
Illustration 3.24 Example of Proper Electrical Installation using
Conduit
Danfoss A/S © Rev. 05/2014 All rights reserved.
Line Power
Control
3 3
Motor
27