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DISCHARGE DEVICES
Resistor Modules
Capacitors with CAPAGRIP K and CAPAGRIP II terminals are
equipped with discharge resistors for a discharge from their
highest nominal voltage rating to less than 50 V within < 60
seconds. For capacitors with CAPAGRIP L and M we offer se-
parate resistor modules. The correct size of the module to be
applied can be selected from the data charts on pages 47f
based on applied voltage, required discharge period, and ca-
pacitance to be discharged.
Alternatively, the resistors to be used for a given capaci-
tance and operating voltage can be calculated by means of DISCHARGE DEVICES
the following formula:
t
three-phase: R
U × 2 R
B
U E C R C
k × C × ln
T
t × 1.5
single-phase: R k = 1 k = 3
U × 2
C B U
× ln
total
E
t ... Discharge period in (s) U ... Operating voltage
B
C ... Partial capacitance of one phase U ... Maximum permissible voltage after period t
E
T
C ... Total capacitance R ... Module resistance value
total
In all cases, the closest smaller discharge module available shall be applied.
The discharge resistors may become very hot (up to 200°C) during continuous operation! »!«
For design L/M only: Remove the lid of the discharge module if applying protective caps to the capacitors!
Sets for CAPAGRIP™ L & M Capacitors (Protection: IP20)
CAPAGRIP™ resistor modules can be connected to single capacitors as well as to groups of parallel units. Both type 1 and 2 are
equally compatible with CAPAGRIP™ L or M terminals.
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