Download VLT Active Filter AAF005 Operating Instructions

VLT Active Filter AAF005
4 How to Install
130BB520.10
For installation where the CT’s connection point can be moved below
conections is also OK. For some few retrofit applications summation CT
are needed to reassure that the capacitor current is not measured.
PCC1
MF
M
4
M
Illustration 4.24: Capacitor bank mounted on PCC but CT’s
installed to reassure that capacitor corrected current is not
measured.
Auto CT detection
The VLT Active Filter is able to perform an auto detection of the installed CT. The ct auto detection can be conducted both while the system is running
and at no load conditions. The filter injects a prefixed current of known amplitude and phase angle and is measuring the returned CT input. The performance is conducted on each phase individually and for several frequencies to reassure phase sequence and that harmonics of different correctly.
The Auto CT detection is pending on the follow conditions:
-
Active filter bigger then 10% of CT RMS rate
-
CT’s installed on source (PCC) side (auto CT not possible for load side CT installation)
-
Only one CT per phase (not possible for summation CT’s)
-
CT’s are part of below standard range:
Sec
1A
Sec
5A
150
200
250
300
400
500
600
750
1000
1250
1500
2000
2500
3000
3500
4000
30
40
50
60
80
100
120
150
200
250
300
400
500
600
700
800
MG.90.V1.02 - VLT® is a registered Danfoss trademark
33