1 Introduction
1.1 Purpose
The purpose of this manual is to provide detailed technical
information and instructions to enable a qualified
technician to identify faults and perform repairs on
frequency converters in the F frame range, including the
12-pulse variation.
It provides the reader with a general view of the unit's
main assemblies and a description of the internal
processing. With this information, technicians should have
an understanding of the frequency converter operation for
troubleshooting and repair.
This manual provides instructions for the frequency
converter models and voltage ranges described in the
tables on the following page.
1.2 VLT FC Product Overview
VLT HVAC Drive series frequency converters are designed
for the HVAC markets. They operate in variable torque
mode or constant torque down to 15 Hz and include
special features and options designed for fan and pump
applications.
VLT
®
AQUA FC 202 series frequency converters are
designed for water and waste water markets. They can
operate in either constant torque or variable torque with
limited overload capabilities. Included are specific features
and options for use on a variety of water pumping and
processing applications.
VLT AutomationDriveseries frequency converters are fully
programmable for either constant torque or variable
torque industrial applications. They are capable of
operating a great variety of applications and incorporate a
wide range of control and communication options.
These models are available in NEMA 1/IP21 or NEMA 12/
IP54 enclosures.
VLT
®
12-Pulse frequency converters are also covered in
these procedures. The VLT 12-pulse frequency converter is
a high power passive solution to reduce harmonic
distortion on mains power lines. Connecting each of the
two 12-pulse frequency converter input rectifiers to a
separately mounted phase shifting transformer naturally
cancels low order current harmonics to levels near 12%. No
special set up or controls are required.
1.3 For Your Safety
1.3.1 Warnings
WARNING
Frequency converters contain dangerous voltages when
connected to mains. Only a competent technician should
carry out service.
WARNING
For dynamic test procedures, main input power is required
and all devices and power supplies connected to mains are
energized at rated voltage. Use extreme caution when
conducting tests in a powered frequency converter.
Contact with powered components could result in
electrical shock and personal injury.
1.
Disconnect mains prior to inspection or making
repairs.
2.
DO NOT touch electrical parts of frequency
converter when connected to mains. After
removing power from mains, wait 40 minutes
before touching any electrical parts. See the label
on the front of the frequency converter door for
specific discharge time.
3.
The STOP key on the control panel does not
disconnect mains.
4.
During operation and while programming
parameters, the motor may start without warning.
Activate the STOP key when changing data.
1.4 Electrostatic Discharge (ESD)
WARNING
When performing service, use proper ESD procedures to
prevent damage to sensitive components.
Many electronic components within the frequency
converter are sensitive to static electricity. Voltages so low
that they cannot be felt, seen or heard can reduce the life,
affect performance, or completely destroy sensitive
electronic components.
Introduction
High Power Service Manual for Modular F Frame Drives
6
MG90K202 - VLT
®
is a registered Danfoss trademark
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