Electronic Circuit Breaker ESS20 - E-T-A - #1

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www.e-t-a.com Electronic Circuit Breaker ESS20-0.. Issue C 5 - 7 5 Description Electronic circuit breaker type ESS20-0.. is designed to ensure selective disconnection of individual loads in systems which are powered by a DC 24 V switch-mode power supply. DC 24 V power supplies, which are widely used in industry today, will shut down the output in the event of an overload with the result that one faulty load in the system can lead to complete disconnection of all loads. As well as an unidentified failure this also means stoppage of the whole system. Through selective disconnection the ESS20-0.. responds much faster to overload or short circuit conditions than the switch-mode power supply. This is achieved by a combination of active current limitation and well-proven circuit breaker technology including physical isolation. The ESS20-0.. limits the highest possible current to 1.8 or 1.5 times the selected rated current of the circuit breaker. Thus it is possible to switch on capacitive loads of up to 20,000 ìF lamp loads, but they are disconnected only in the event of an overload or short circuit. For optimal adjustment to the application conditions the current rating of the ESS20-0.. can be selected in fixed values from 0.5 A...10 A and in adjustable variants 1 A/2 A or 3 A/6 A. Failure and status indication are provided by a bicolour LED and an integral signal contact. The ESS20-0.. features a width of only 12.5 mm and can be plugged into the E-T-A power distribution socket Module 17plus and SVS02/ SVS04 (for ESS20-003) ensuring ease of installation and saving space in control cabinets. Features Approvals �œ Selective load protection with physical isolation in the event of a fault. �œ All types of loads can be connected (small DC motors etc. on request). �œ Active current limitation (1.8 or 1.5 times rated current IN = 8 A or 10 A) for safe connection of capacitive loads up to 20,000 ìF and on overload/short circuit. �œ Electronic trip characteristic. �œ Reliable overload disconnection with 1.1 x IN plus, even with long load lines or small cable cross sections (see table 2). �œ Selectable current ratings (fixed values 0.5 A...10 A or two steps: 1 A/2 A or 3 A/6 A). �œ Manual ON/OFF button (push-push actuation). �œ Clear status and failure indication. �œ Width per unit only 12.5 mm. �œ Plug-in mounting utilising power distribution system Module 17plus or SVS02/SVS04 ( for ESS20-003), see product group 7. ESS20-0.. Technical data (Tambient = 25 °C, operating voltage US = DC 24 V) Authority Voltage rating Current ratings UL 1077 DC 24 V 0.5...10 A Attention: the user has to make sure that the cable cross sections of the relevant load circuit are suitable for the current rating of the ESS20 used. Operating data Operating voltage US DC 24 V (18...32 V) Current rating IN fixed current ratings: 0.5 A, 1 A, 2 A, 3 A, 4 A, 6 A, 8 A, 10 A switchable: 1 A/2 A or 3 A/6 A Power consumption typically 13 mA Trip current (bimetal) typically 0.3 A (only in the event of a failure, before physical isolation) Status indication bicolour LED: by means of GREEN: unit is ON, power-MOSFET is switched on ORANGE: in the event of overload or short circuit until physical isolation LED not lighted: push button in OFF position potential-free signal contact (changeover contact) OFF-position of push button Reverse polarity internal bimetal (fail-safe element) trips, protection of US push button moves into OFF position Load circuit Load output Power-MOSFET switching output (high side switch) Max. data of load with side-by-side mounting see table 1 Voltage drop at IN see table 1 Overload disconnection typically 1.1 x IN (1.05...1.35 x IN) Short-circuit current IK typically 1.8 x IN / active current limitation Trip time see time/current characteristics for physical isolation typically 5 sec at Iload > 1.1 x IN for electronic disconnection typically 5 sec...100 ms at Iload > 1.8 x IN or 1.5 x IN Temperature disconnection internal temperature monitoring with physical isolation Low voltage monitoring load output ON at US >16 V OFF at US < 8 V Starting delay tstart typically 0.3 sec after every switch-on and after applying US Disconnection of load circuit single pole (switch contact) - by push-push actuation of the blue push button - upon electronic fault disconnection (overload, short circuit) - with reverse polarity Free-wheeling circuit external free-wheeling diode recommended with inductive load Several load outputs must not be connected in parallel.