Installation requirements:
The overall electrical safety of the frequency converter requires special installation considerations regarding:
• Fuses and circuit breakers for over-current and short-circuit protection
• Selection of power cables (mains, motor, brake, loadsharing and relay)
• Grid configuration (IT,TN, grounded leg, etc.)
• Safety of low-voltage ports (PELV conditions).
Consult the relevant clauses in these instructions and in the
VLT HVAC Drive Design Guide
for information about the installation requirements.
1.2.6 Caution
Caution
The frequency converter DC link capacitors remain charged after power has been disconnected. To avoid an electrical shock hazard, disconnect the
frequency converter from the mains before carrying out maintenance. Wait at least as follows before doing service on the frequency converter:
Voltage
Minimum Waiting Time
4 min. 15 min. 20 min. 30 min. 40 min.
200 - 240 V 1.1 - 3.7 kW 5.5 - 45 kW
380 - 480 V 1.1 - 7.5 kW 11 - 90 kW 110 -200 kW 250 - 450 kW
525 - 600 V 1.1 - 7.5 kW 110 - 250 kW 315 - 560 kW
Be aware that there may be high voltage on the DC link even when the LEDs are turned off.
1.2.7 Installation at high altitudes (PELV)
By altitudes above 2 km, please contact Danfoss regarding PELV.
1.2.8 Avoid unintended start
While the frequency converter is connected to mains, the motor can be started/stopped using digital commands, bus commands,
references or via the Local Control Panel.
• Disconnect the frequency converter from mains whenever personal safety considerations make it necessary to avoid unintended start.
• To avoid unintended start, always activate the [OFF] key before changing parameters.
• Unless terminal 37 is turned off, an electronic fault, temporary overload, a fault in the mains supply, or lost motor connection may cause a
stopped motor to start.
1.2.9 Safe Stop of the frequency converter
For versions fitted with a Safe Stop terminal 37 input, the frequency converter can perform the safety function
Safe Torque Off
(As defined by draft CD
IEC 61800-5-2) or
Stop Category 0
(as defined in EN 60204-1).
It is designed and approved suitable for the requirements of Safety Category 3 in EN 954-1. This functionality is called Safe Stop. Prior to integration and
use of Safe Stop in an installation, a thorough risk analysis on the installation must be carried out in order to determine whether the Safe Stop functionality
and safety category are appropriate and sufficient. In order to install and use the Safe Stop function in accordance with the requirements of Safety
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HVAC Drive Applications
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