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Viper Expansion Unit for SCR-i Safety Relays (SEU-31-i)

The SEU-31-i is an expansion unit for the VIPER SCR-i range and has been designed to connect to a standard SCR-i safety relay to offer extra safety output contacts (3NC + 1NO).

  • Outputs 3NC and 1NO contacts
  • Up to PLe, SIL 3, Category 4

Part NumberDescriptionInputsOutputsAuxiliarySupplyTerminals
280007SEU-31-i Screw Terminals 24V03 N/C1 N/O24VdcScrew
280007-PSEU-31-i Pluggable Terminals 24V03 N/C1 N/O24VdcPluggable

Must be used in conjunction with SCR-i Safety Relay.

Power supply Circuit
Operating voltage24V AC/DC
Operating voltage tolerance-15% - +10%
Rated supply frequency50Hz – 60Hz
Rated supply current60mA
Power consumption24V AC/DC 2.5W

Control Circuits
Rated output voltageS11 24V DC
Input currentS15, S16 100mA
Response Time25ms
Release Time25ms
Recovery TimeApprox. 1s

Output Circuits
Rated Output Voltage250VAC
Max. Current per output6A
Max. Total current all outputs6A
Safety contact breaking CapacityAC 230V, 4A for AC-15 / DC 24V, 30W, 2A, DC-13
Minimum contact load10V 10mA
Min. Contact fuses4A slow blow, 6A fast blow
Contact materialAgSnO2
Contact service life10 x 10 6

General Data
Rated impulse withstand voltage4kV (Creepage and Clearance: Outputs -> Control Circuits: 5.5mm)
Rated insulation voltage250V
Degree of protectionIP20
Temperature range-20C + 55C
Degree of contamination2
Overvoltage CategoryIII
MountingAny Position