Page 45 - ELECTRONICON_Katalog_PFC-60Hz
P. 45

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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