Application Description Used in automation systems, electromechanical relays guarantee a safe connection between process I/O and electronic controls. The following functions are covered by relay coupling elements: • Electrical isolation between the input and output circuits • Independence of the type of switching current (AC and DC) • High short-term overload resistance in the event of short circuits or voltage peaks • Low switching losses • Ease of operation
Accessories Power Terminal Block The XRAPLCESK power terminal block has the same shape as the relay modules and is used to feed in the bridging potentials. The nominal current is 32 A. When the total current is less than or equal to 6 A, supply can take place directly at the connecting terminal blocks of one of the connected relays.
End Cover The XRAATPBK end cover is required at the start and stop of a relay strip. It can also be used for visual separation of groups of relays as well as separating relays with voltages greater than 250V and separating neighboring bridges with different potentials. It is equipped with pre-scored break out points at the bridging positions so that individual bridges can be passed through as needed. It may also be necessary to use the end cover between adjacent relays when three phases (L1, L2, L3) are used on the contact side of the relay.
Bridges The XRAFBST colored, insulated plugin bridge system reduces wiring time by up to 70% compared to conventionally wired relays. The XRAFBST2, 2-position bridges, are suited for bridging a smaller number of relays and total currents <6 A. When a circuit is supplied from both sides, the circuit can be opened at any point, allowing all other modules to continue being supplied at the same time. The XRAFBST500 allow up to 80 modules to be bridged at one time. If bridges with different potentials meet in neighboring modules, the end cover XRAATPBK should be used. All bridges are equipped with a groove for removal with a standard screwdriver.
SPECIFICATIONS Input Voltage: XRU1D24: 24 Vdc XRU1D24U: 24 Vac/Vdc XRU1D120U: 120 Vac/110 Vdc Typical Input Current: XRU1D24: 9 mA XRU1D24U: 11 mA (24 Vac), 8.5 mA (24 Vdc) XRU1D120U: 3.5 mA (120 Vac), 3 mA (110 Vdc) Connection Type: Screw connection Rigid Solid AWG (mm2): 26 to 14 (0.14 to 2.5) Flexible Stranded AWG (mm2): 26 to 14 (0.14 to 2.5) Typical Response Time: XRU1D24: 5 mS XRU1D24U and XRU1D120U: 6 mS Typical Release Time: XRU1D24: 8 mS XRU1D24U and XRU1D120U: 15 mS Input Protection: XRU1D24: Polarity protection diode, free-wheeling diode XRU1D24U and XRU1D120U: Bridge rectifier Contact Type: SPDT Contact Material: AgSnO Max Switching Voltage: 250 Vac/Vdc1 Min Switching Voltage: 12 Vac/Vdc Limiting Continuous Current: 6 A Min Switching Current: 10 mA Min Switching Power: 120 mW Ambient Temp Range: -20 to 60°C (-4 to 140°F) Rated Operating Mode: 100% operating factor Inflammability Class: V0, in accordance with UL 94 Mechanical Service Life: 2 x 107 cycles *The separating plate, XRAPLCESK, should be installed for voltages greater than 250V (L1, L2, L3) between identical terminal points of adjacent modules. Potential bridging is then possible with the XRAFBST bridge system.