General Warning; Before Commencing Repair Work; Special Conditions - Danfoss VLT AQUA Instruction

2 Safety

2.1.2 General Warning

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, (linkage of DC intermediate circuit), as well as the motor connection
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for kinetic backup.
Before touching any potentially live parts of the adjustable frequency drive, wait at least as follows:
380–480 V, 215–335 hp [160–250 kW], wait at least 20 minutes.
380–480 V, 450–950 hp [315–710 kW], wait at least 40 minutes.
Shorter time is allowed only if indicated on the nameplate for the specific unit. Be aware that there may be high voltage on the DC
links even when the control card LEDs are turned off. A red LED is mounted on a circuit board inside both the drive and the active filter
to indicate the DC bus voltages. The red LED will stay lit until the DC link is 50 VDC or lower.
Leakage Current
The ground leakage current from the adjustable frequency drive exceeds 3.5 mA. According to IEC 61800-5-1, a reinforced protective
ground connection must be ensured by means of: a min. 0.015 in² [10 mm²] Cu or 0.025 in² [16 mm²] Al PE wire or an additional PE
wire - with the same cable cross-section as the line power wiring - must be terminated separately.
Residual Current Device
This product can cause DC current in the protective conductor. Where a residual current device (RCD) is used for extra protection, only
an RCD of Type B (time delayed) shall be used on the supply side of this product. See also RCD Application Note MN.90.GX.02.
Protective grounding of the adjustable frequency drive and the use of RCDs must always follow national and local regulations.

2.1.3 Before Commencing Repair Work

1. Disconnect the adjustable frequency drive from line power.
2. Disconnect DC bus terminals 88 and 89
3. Wait at least the time mentioned above in the section General Warning.
4. Remove motor cable

2.1.4 Special conditions

Electrical ratings:
The rating indicated on the nameplate of the adjustable frequency drive is based on a typical 3-phase line power supply within the specified voltage,
current and temperature ranges, which are expected to be used in most applications.
The adjustable frequency drives also support other special applications, which affect the electrical ratings of the adjustable frequency
drive. Special conditions that affect the electrical ratings might be:
• Single phase applications.
• High temperature applications which require derating of the electrical ratings
• Marine applications with more severe environmental conditions.
Consult the relevant clauses in these instructions and in the Design Guide for information about the electrical ratings.
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MG.20.T1.22 - VLT is a registered Danfoss trademark
VLT AQUA Low Harmonic Drive Instruction
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