2 Safety
2.1.1 Safety note
The voltage of the adjustable frequency drive is dangerous whenever connected to line power. Incorrect installation of the motor,
adjustable frequency drive or serial communication bus may cause damage to the equipment, serious personal injury or death. Con-
sequently, the instructions in this manual, as well as national and local rules and safety regulations, must be complied with.
Safety Regulations
1.
The adjustable frequency drive must be disconnected from line power if repair work is to be carried out. Make sure that the line power supply
has been disconnected and that the necessary time has passed before removing motor and line power plugs.
2.
The [STOP/RESET] key on the control panel of the adjustable frequency drive does not disconnect the equipment from line power and is thus
not to be used as a safety switch.
3.
Correct protective grounding 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 ground leakage currents are higher than 3.5 mA.
5.
Protection against motor overload is set by par. 1-90
Motor Thermal Protection
. If this function is desired, set par. 1-90 to data value [ETR trip]
(default value) or data value [ETR warning]. Note: The function is initialized 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 line power supply while the adjustable frequency drive is connected to line power. Make sure that
the line power supply has been disconnected and that the necessary time has passed before removing motor and line power plugs.
7.
Please note that the adjustable frequency drive has more voltage inputs than L1, L2 and L3 when load sharing (linking of the DC intermediate
circuit) and external 24 V DC have been installed. Make sure that all voltage inputs have been disconnected and that the necessary time has
passed before commencing repair work.
Installation at High Altitudes
Installation at high altitude:
At altitudes above 9843 ft [3 km], please contact Danfoss Drives regarding PELV.
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 adjustable frequency drive
is connected to line power. If personal safety considerations 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 key [RESET] 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 adjustable frequency drive, or if a temporary
overload or a fault in the supply line power or the motor connection ceases.
Warning:
Touching the electrical parts may be fatal - even after the equipment has been disconnected from line power.
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 backup.
VLT HVAC Low Harmonic Drive Instruction
Manual
2 Safety
MG.16.A1.22 - VLT
®
is a registered Danfoss trademark
2-1
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