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2 Introduction
2.1 Safety
2.1.1 Safety Note
WARNING
The voltage of the frequency converter is dangerous
whenever connected to mains. Incorrect installation of the
motor, frequency converter or fieldbus may cause death,
serious personal injury or damage to the equipment.
Consequently, the instructions in this manual, as well as
national and local rules and safety regulations, must be
complied with.
Safety Regulations
1.
The frequency converter must be disconnected
from mains if repair work is to be carried out.
Check that the mains supply has been discon-
nected and that the necessary time has passed
before removing motor and mains plugs.
2.
The [Stop/Reset] key on the LCP of the frequency
converter does not disconnect the equipment
from mains and is thus not to be used as a safety
switch.
3.
Correct protective earthing of the equipment
must be established, the user must be protected
against supply voltage, and the motor must be
protected against overload in accordance with
applicable national and local regulations.
4.
The earth leakage currents are higher than 3.5
mA.
5.
Protection against motor overload is set by
1-90 Motor Thermal Protection
. If this function is
desired, set
1-90 Motor Thermal Protection
to data
value [ETR trip] (default value) or data value [ETR
warning]. Note: The function is initialised at 1.16 x
rated motor current and rated motor frequency.
For the North American market: The ETR
functions provide class 20 motor overload
protection in accordance with NEC.
6.
Do not remove the plugs for the motor and
mains supply while the frequency converter is
connected to mains. Check that the mains supply
has been disconnected and that the necessary
time has passed before removing motor and
mains plugs.
7.
Note that the frequency converter has more
voltage inputs than L1, L2 and L3, when load
sharing (linking of DC intermediate circuit) and
external 24 V DC have been installed. Check that
all voltage inputs have been disconnected and
that the necessary time has passed before
commencing repair work.
Installation at high altitudes
CAUTION
380-480 V, enclosure A, B and C: At altitudes above 2 km,
contact Danfoss regarding PELV.
380-480 V, enclosure D: At altitudes above 3 km, contact
Danfoss regarding PELV.
525-690 V: At altitudes above 2 km, contact Danfoss
regarding PELV.
WARNING
Warning against Unintended Start
1.
The motor can be brought to a stop by means of
digital commands, bus commands, references or
a local stop, while the frequency converter is
connected to mains. If personal safety consider-
ations make it necessary to ensure that no
unintended start occurs, these stop functions are
not sufficient.
2.
While parameters are being changed, the motor
may start. Consequently, the [Stop/Reset] key
must always be activated; following which data
can be modified.
3.
A motor that has been stopped may start if faults
occur in the electronics of the frequency
converter, or if a temporary overload or a fault in
the supply mains or the motor connection ceases.
WARNING
Touching the electrical parts may be fatal - even after the
equipment has been disconnected from mains.
Also make sure that other voltage inputs have been
disconnected, such as external 24 V DC, load sharing
(linkage of DC intermediate circuit), as well as the motor
connection for kinetic back up. Refer to the Operating
Instructions for further safety guidelines.
Introduction
VLT
®
Refrigeration Drive Design Guide
10
MG16G102 - VLT
®
is a registered Danfoss trademark
2
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