Fuses - Danfoss VLT AAF00x Instruction Manual

How to Install
4 4
PCC1
Figure 4.37 Un-allowed installation. Corrected capacitor current
interacts with CT measurement.
PCC1
Figure 4.38 CT installation does not measure capacitor current.
4-28
VLT Active Filter AAF 00x
AAF
M M
AAF
M M
MG.90.V2.22 - VLT
For installations where the CT connection point can be
moved, Figure 4.38 is also possible. In some retrofit
applications, summation CT is needed to ensure that the
capacitor current is not measured.
Summation CT can also be used to subtract two signals
from each other, i.e. the capacitor bank corrected current
from the total current.
PCC1
Figure 4.39 Capacitor bank mounted on PCC, but CTs installed
to ensure that capacitor corrected current is not measured.

4.5.11 Fuses

Branch circuit protection:
In order to protect the installation against electrical and
fire hazard, all branch circuits in an installation, switch
gear, machines, etc., must be short-circuited and
overcurrent protected according to national/international
regulations.
Short-circuit protection:
The active filter must be protected against short-circuit to
avoid electrical or fire hazard. Danfoss recommends using
the fuses mentioned below to protect service personnel
and equipment in case of an internal failure in the device.
Overcurrent protection
The active filter is equipped with an internal overcurrent
protection that avoids overload in normal running
conditions. Overload protection is however needed in case
®
is a registered Danfoss trademark
AAF
M
M