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2 Safety
2.1 Safety Precautions
WARNING
HIGH VOLTAGE
AC drives contain high voltage when connected to AC mains input, DC supply, or load sharing. Failure to perform installation,
start-up, and maintenance by qualified personnel can result in death or serious injury.
-
Only qualified personnel must perform installation, start-up, and maintenance.
WARNING
UNINTENDED START
When the drive is connected to the AC mains, DC supply, or load sharing, the motor may start at any time, causing risk of death,
serious injury, and equipment or property damage. The motor may start by activation of an external switch, a fieldbus
command, an input reference signal from the LCP or LOP, via remote operation using MCT 10 Set-up software, or after a cleared
fault condition.
-
Press [Off] on the LCP before programming parameters.
-
Disconnect the drive from the mains whenever personal safety considerations make it necessary to avoid unintended
motor start.
-
Check that the drive, motor, and any driven equipment are in operational readiness.
WARNING
DISCHARGE TIME
The drive contains DC-link capacitors, which can remain charged even when the drive is not powered. High voltage can be
present even when the warning indicator lights are off.
Failure to wait the specified time after power has been removed before performing service or repair work could result in death
or serious injury.
-
Stop the motor.
-
Disconnect AC mains, permanent magnet type motors, and remote DC-link supplies, including battery back-ups, UPS, and
DC-link connections to other drives.
-
Wait for the capacitors to discharge fully. The minimum waiting time is specified in the table
Discharge time
and is also
visible on the nameplate on top of the drive.
-
Before performing any service or repair work, use an appropriate voltage measuring device to make sure that the capacitors
are fully discharged.
Table 4: Discharge Time, VLT® HVAC Drive FC 102 and VLT® Refrigeration Drive FC 103
Voltage [V]
Minimum waiting time (minutes)
4
7
15
200–240
1.1–3.7 kW (1.5–5 hp)
–
5.5–45 kW (7.5–60 hp)
380–480
1.1–7.5 kW (1.5–10 hp)
–
11–90 kW (15–125 hp)
525–600
1.1–7.5 kW (1.5–10 hp)
–
11–90 kW (15–125 hp)
Safety
Operating Guide | VLT® Extended Relay Card MCB 113
AQ322553864968en-000101 / 130R0353
8 | Danfoss A/S © 2020.01