Danfoss VLT AQUA Drive Design Manual page 158

8. Troubleshooting
WARNING/ALARM 4
Line phase loss:
A phase is missing on the supply side, or the
line voltage imbalance is too high.
This message also appears in case of a fault
in the input rectifier on the adjustable fre-
quency drive.
Check the supply voltage and supply currents
to the adjustable frequency drive.
WARNING 5
DC link voltage high:
The intermediate circuit voltage (DC) is higher
than the overvoltage limit of the control sys-
tem. The adjustable frequency drive is still
active.
WARNING 6
DC link voltage low
The intermediate circuit voltage (DC) is below
the undervoltage limit of the control system.
The adjustable frequency drive is still active.
8
WARNING/ALARM 7
DC overvoltage:
If the intermediate circuit voltage exceeds the
limit, the adjustable frequency drive trips after
a given period of time.
Possible corrections:
Selecting OVC function will extend the ramp
times.
158
Select Over Voltage Control function
in par. 2-17
Connect a brake resistor
Extend the ramp time
Activate functions in par. 2-10
Increase par. 14-26
MG.20.N2.22 - VLT
Alarm/warning limits:
VLT AQUA 3 x 200-240
V AC
Undervoltage
Voltage warning
low
Voltage warning 390/405
high (w/o brake -
w/brake)
Overvoltage
The voltages stated are the intermediate circuit
voltage of the VLT AQUA with a tolerance of ±
5 %. The corresponding line voltage is the in-
termediate circuit voltage (DC link) divided by
1.35.
WARNING/ALARM 8
DC undervoltage:
If the intermediate circuit voltage (DC) drops
below the "voltage warning low" limit (see ta-
ble above), the adjustable frequency drive
checks if 24 V backup supply is connected.
If no 24 V backup supply is connected, the
adjustable frequency drive trips after a given
period of time, depending on the unit.
To check whether the supply voltage matches
the adjustable frequency drive, see 3.2
eral Specifications .
WARNING/ALARM 9
Inverter overloaded:
The adjustable frequency drive is about to cut
out because of an overload (too high current
for too long). The counter for electronic, ther-
mal inverter protection gives a warning at
98% and trips at 100%, while giving an alarm.
You cannot reset the adjustable frequency
drive until the counter is below 90%.
The fault is that the adjustable frequency
drive has been overloaded by more than nom-
inal current for too long.
WARNING/ALARM 10
Motor ETR overtemperature:
According to the electronic thermal protection
(ETR), the motor is too hot. You can choose if
you want the adjustable frequency drive to
give a warning or an alarm when the counter
reaches 100% in par. 1-90. The fault is that
the motor has been overloaded by more than
nominal current for too long. Check that the
motor par. 1-24 is set correctly.
® is a registered Danfoss trademark.
VLT ® AQUA Drive Design Guide
3 x 380-500
V AC
[VDC] [VDC]
185 373
205 410
810/840
410 855
Gen-