Danfoss VLT 28 Manual

I High voltage warning
The voltage of the adjustable frequency
drive is dangerous whenever the drive is
connected to electrical current. Incorrect
fitting of the motor or adjustable frequency drive may
cause damage to the equipment, serious injury or
death. Consequently, it is essential to comply with
the instructions in this manual as well as local and
national rules and safety regulations.
I These rules concern your safety:
1. Disconnect the adjustable frequency drive from
the AC line if repair work is to be carried out. Wait
4 minutes to allow for electrical discharge before
removing motor and AC line connectors.
2. The [STOP/RESET] key on the control panel
of the adjustable frequency drive does not
disconnect the equipment from the AC line.
Do not use it as a safety switch.
3. The unit must be grounded correctly. The user
must be protected against supply voltage and the
motor protected against overload in accordance
with applicable national and local regulations.
4. The ground leakage currents are higher than 3.5 mA.
5. Protection against motor overload is not included in
the factory setting. If this function is required, set
parameter 128 Motor thermal protection to ETR
trip or ETR warning. For North America: The ETR
functions provide class 20 overload protection for
the motor, in accordance with NEC requirements.
6. Do not remove the terminal plugs for the motor
and AC line supply while the adjustable frequency
drive is connected to the AC line. Ensure that
the AC line supply has been disconnected and
It can be extremely dangerous to touch the electrical parts
even when the mains supply has been disconnected.
Also ensure that other voltage inputs are disconnected
from load sharing through the DC bus.
Wait at least 4 minutes after the input power has been
removed before servicing the drive.
195NA139.10
4
VLT® 2800 Series
that 4 minutes has passed before removing
motor and AC line plugs.
7. The DC bus terminals are another high voltage
input that must be disconnected before servicing
the drive. Ensure that all voltage inputs have
been disconnected and that 4 minutes has
passed before repair work begins.
I Warnings against unintended start:
1. The motor can be started by means of digital
commands, bus commands, references or
a local start command whenever the drive
is connected to the AC line. Therefore, an
unintended start may occur anytime power is
applied. Never service the drive or equipment
when power is applied to the drive.
2. The motor may start while parameters are
being changed. Always activate the stop key
[STOP/RESET] by pressing it before data is modified.
3. A motor that has been stopped may start if
faults occur in the electronics of the drive, or
if a temporary overload or fault clears in the
AC line or motor connection.
I Motor overload protection
The electronic thermal relay (ETR) in UL listed
VLTs provides Class 20 motor overload protection
in accordance with the NEC in single motor
applications when parameter 128 is set for "ETR
TRIP" and parameter 105 Motor current is set
for the rated motor current.
Warning:
MG.28.A8.22 - VLT is a registered Danfoss trademark