Buffering: Electrolytic caps. instead of accumulators CB scheme Data sheet • Buffering for 24V loads • Minimum hold-up time: 0.2s/20A (max. buffer time depends on load) • Fit for industrial use: Energy storage in electrolytic caps., no accumulators • Clear status indication by Status LED and signalling terminals Short description The buffer unit is a supplementary device for regulated DC 24V power supplies. It buffers load currents during typical mains faults and switching events or load peaks. Working principle Charge Buffer In times when the power supply proviDC des sufficient voltage, the buffer unit Discharge stores energy in integrated electrolytic capacitors. In case of a mains voltage fault, this energy is released again in a regulated process. Bridges mains faults without AC interruption Statistics show that 80 percent of all DC mains faults last less than 0.2s. These Buffer unit mains faults are completely bridged by the buffer unit and will have no influence on the DC power (startup-delay of power supply used might be taken under consideration. This increases the reliability of the system as a whole. Extended hold-up time Once the main power fails or is swit- AC ched off, the buffer unit will contiDC nue to provide the load current for a Buffer unit defined period of time. Process data can be saved and processes can be terminated before the DC power switches off. Controlled restarts are subsequently possible. Easy to handle, expandable and maintenance-free The buffer unit does not require any control wiring. It can be added parallel to the load circuit at any given point. Any given number of buffer units can be switched parallel to increase the output capacity or the hold-up time. The dual terminals allow for easy wiring. In addition, there is a housing connection. Short Overview - Technical Data Short Overview - Technical Data Rated voltage Idling input current Voltage range Power dissipation Buffered voltage selectable by front jumper setting Vin -1V: 23 - 27.8V (variable threshold) 22.5V fixed: 22.5V (fixed threshold) Dimensions (W x H x D) 64mm x 124mm x 102mm (without DIN rail) Weight Reversed power immunity Protection against polarity reversal Charging current Buffering current Current limitation (Buffer operation) Charging time Hold-up time • minimum • typical Safety Terminal voltage Isolation resistance Penetration protection > 3.5 x 3.5 mm Internal fusing Galvanic isolation to signal path Order information Order number DIN rail electrolytic capacitor buffer unit Mating connector for signalling terminals (part of delivery) Adapter for S7-300 rail Wall mounting set (two pcs. per package) 1/4

Data sheet Technical Data Buffer Charging Charging delay time Charging current Charging time 18...27s (primary charge / cold start) Buffer Operation Rated output current Current limitation Hold-up time • minimum • typical To increase buffer current and/or extend hold-up time any given number of buffer unit can be switched parallel (max. load per terminal = 30A) Activation threshold “22.5V fixed” Buffering starts if terminal voltage <22.5V, voltage is kept at 22.5V. Buffering starts if terminal voltage decreases by more than 1V, faster than typ. 0.54V/s. Voltage is kept at that level. Buffering...

Data sheet Electromagnetic Compatibility(EMC) Connections Terminals Fingertouch-proof terminals with captive screws for 5.5mm slotted screwdriver or Philips cross-recessed screwdriver No. 2 EN 61000-6-3 (also includes EN 61000-6-4) radiated noise and interference voltage on DC lines Easy to reach terminals on the front panel. Signal connectors and powers terminals are clearly separate from each other. Immunity • Electrostatic Discharge (ESD) Tightening torque EN 61000-6-2 (also includes EN 61000-6-1) EN 61000-4-2, Level 4 (withstands 8kV direct discharge, 15kV air discharge; DIN rail earthed)...

Data sheet Voltage Monitor Buffer Capacitor Charger & Inrush Buffer Capacitor Active Monitor Optocoupler Signalling Terminals Signal outputs Voltage drop across opto coupler Leakage current low ohmic, while buffer capacitors are dis- low ohmic, when buffer is fully charged <1 OOuA (while optocoupler blocks) Signal input Shutdown threshold Input current 'High' input signal initiates unit shutdown Isolation voltage AC 500V against power path Signal outputs and control input are protected against short-circuit, open circuit and overload. Signalling output variants: power supply Installation Notes...