Schaffner Group
User and Installation Manual
LCL Filter
May 2018
12/21
3.3 Cooling requirement
Please notice that only the 380A LCL filters have an embedded fan and powered supply. The lower rated
LCL filters do not require forced air cooling.
3.4 Damping resistors
The versions E0xxR have in use power resistors to ensure proper damping of the switching frequency.
The damping resistors are designed to dissipate the energy in the resonance circuit. Thus the damping
resistors can reach temperatures as high as 275°C!
Caution: risk of burning - do not touch the damping resistors during operation.
3.5 Circuit breaker
The ratings 160, 250 and 380A have installed a circuit breaker in the capacitor circuit to ensure safe
capacitor disconnection in case of a short circuit. Because the capacitors are limited to a short circuit
current of 10’000A, a safety device must be installed to protect the capacitors.
For the ratings 25, 50 and 80A the impedance of the line choke is limiting the current to a value < 10 kA.
By default, the circuit breakers are set to status “on”.
Auxiliary contacts are provided along with the circuit breaker, with one NC normally closed and one NO
normally open contact. The NO auxiliary contact must be used in the control system to ensure the
interruption of the power branch the filter is connected to. The NC auxiliary contact is avaialble to be
used for signalling and/or warning purpose.
The circuit breaker must never be switched-off manually when the application is in operation or under
voltage. There is a risk of electrical shock when doing so!
3.6 Mechanical frame sizes
The components of the LCL filters FN6840 are implemented on a base plate or base frame with 4
different frame sizes, Frame D to Frame H, from the lowest to the highest rating. Dimensions and
footprint are provided in section .
Figure 2: Overview of all IP 00 frame size versions
INS 1008766 A0
INS 1008766 A0
INS 1008766 A
