Accesories
Inrush current limiter
RESBE and RESBD
Inrush current limiter, single and three phase
When energy consumers are switched on, inrush current surges can occur, which can lead to undesirable tripping of the fuse elements. In order to provide selective protection, it is advisable to use inrush current limiters in such cases.
Generally:
By connecting our inrush current limiters from the RESBE and RESBD series, commercially available fuses and circuit breakers can be used.
The RESBE and RESBD series implements our patent application “Inrush current limitation with time-controlled second switching element”.
To eliminate the bridging current surge, the duty cycle of the load should be greater than the duration of the inrush current limiter. If this cannot be achieved, we recommend the “Enable output” option for loads with a release input or with a remote input/output input.
Inrush current avoider
REVRL
Generally:
The transformer switching relay (REVRL) is used to smoothly switch one or more single-phase transformers when idle or under load without inrush current. The soft switch-on process avoids the switch-on surge current and not just limits it – as with conventional switch-on current limiters.
The REVRL is simply connected between the power switch and the transformer. It can also be used as a power switch when operated via the control input (there is no electrical isolation in this application).
Areas of application:
The REVRL is used, for example, in isolation, control, heating and vehicle transformers as well as in industry, plant engineering and research. Suitable for inductive and capacitive loads.
Features:
Soft switch-on procedure
The REVRL pre-magnetizes the transformer with unipolar voltage pulses before full switch-on. The strength of the bias magnetization is the same for every transformer and should be one
Reach the turning point of the hysteresis curve. The width of the voltage pulses required for this must be adapted to the different transformer types such as package core or toroidal core transformers. The potentiometer (TP1) in the REVRL is used for this purpose.
Further options and designs available on request
Pre-magnetization unit
REVVE
Generally:
The premagnetization unit REVVE is used to avoid inrush currents from large transformers. Using a special process, transformers with a power of up to 800 kVA (and higher) can be switched off with the help of a premagnetization unit and contactor circuitry. In conjunction with the REVVE, even large transformers can be protected on the primary side with fast fuses at rated current. The primary-side fuse provides both short-circuit and overload protection.
Execution:
The main transformer is premagnetized via a small premagnetization unit, contactor circuitry and control electronics and can be switched without inrush current. The control electronics controls up to three external contactors. The premagnetization unit is activated with the first contactor. The second contactor bridges the bias unit and switches the load transformer fully on. The third contactor is optional to freely switch on the output of the load transformer, as this type of inrush current surge prevention works optimally for load transformers when idle. By using external contactors, the REVVE can be used in both single-phase and three-phase applications.
Technical data:
Netzspannung | 400V bis 690 V ± 10% (einphasig oder dreiphasig) |
Netzfrequenz | 50/60 Hz ± 10% (45 … 65 Hz) |
Leistungen | bis 800 kVA (höhere Leistungen auf Anfrage) |
Umgebungstemperatur | – 20 °C … + 70 °C |
Feuchtigkeit | 95 % (nicht kondensierend) |
Schutzart | IP 00 (andere Schutzarten auf Anfrage möglich) |
Anschlüsse | Klemmen (Schraubanschluss) |