Danfoss VLT AFE 302 Operating Instructions Manual page 17

Crane System Design
3 3
•
Open the input contactor between AFE and LCL
filter.
•
Verify that the input voltage is balanced three
phase 630V AC line-to-line RMS.
•
Apply power to the LCL filter and verify that the
rms current magnitude measured is approximately
same as the calculation using the following
formula:
630 × 314 ×
i =
capacitance, delta value.
•
Leave the AFE main contactors open and disallow
the AFE start signal in the PLC.
•
Soft charge the system but do not enable the main
contactor.
•
Let the softcharge circuit active for about 5min.
•
Check the voltage at the AFE Mains side when the
AFE is powered up by softcharge. The voltage
between all phases should be 0V. Also the voltage
between the phases L1/L2/L3 and earth should be
0V. Please call Danfoss service if you can measure a
voltage greater then 10V here.
Do not switch on the mains contactors if you
measure a voltage more than 10V here.
•
Verify that all LCPs read the DC link voltage to
within ±2% of a calibrated voltage meter. The
expected voltage value is:
V DC + 5 / − 10 % = ( V mains _ LL _ RMS × 2 + 5 / − 10 %
890
= 630 × 1, 414 + 5 / − 10 % )
•
Download all the AFE and frequency converter
settings with .
1.
2.
3.
4.
5.
6.
16
®
VLT
4.1 Red wire of MK105 to phase R.
4.2 White wire of MK105 to phase
S.
4.3 Black wire of MK105 to phase T.
4.4
All should be <0.2Ω.
C × 3
, where C is the LCL filter
3
Capacitance value of output filter must
be star equivalent.
Danfoss Drives output filters are always
marked with star equivalent values.
Set the right LCL filter values in the AFE,
the capacitance value of the LCL filter
shall be entered in as delta equivalent.
Set the right mains values in the AFE.
Par. group 4-** Output Limits AFE – use
factory settings.
Total system capacitance par. 7-60 must
be programmed with a sum of the DC-
link capacitance x 0,9.
MG.33.X2.02 - VLT
Active Front End AFE 302 Operating Instructions Liebherr
7.
•
Switch Crane off.
•
Program the PLC to the normal start-up sequence.
•
Switch Crane on.
•
The AFE starts, but not any of the inverters, and
verify that the AFE and inverter LCP readings are
975V DC and that they are within ±2% of a
calibrated voltage meter.
•
Check if all fans are running after closing the mains
contactor.
•
Start checking inverters and motors.
•
Save all parameter settings with .
•
For the crane commissioning, measure THDu and
THDi of the 630V and 400V terminals and
document the results in the commissioning
certificate.
•
Verify that the THD levels of the 400V terminal are
complied to EN 61000-3 or other country specified
harmonic requirements.
®
is a registered Danfoss trademark
Use par. group 7-** Controllers as follows:
•
Par. 7-61 DC-Link Reference is
changed from 980V (default) to
975V.
•
Par. 7-62 DC-Link PI Proportional
Gain (Kp) is calculated internally
based on the power size and DC
capacitance in par. 7-60.
Recommend to use the default
value. The wrong setting could
cause the unstable DC voltage
regulation.
•
Par. 7-63 DC-Link PI Integral Time
(Ti) is changed to 5ms.