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Viper Expansion Unit with Time Delay for SCR-i Safety Relays (SEU-31TD-i)

The SEU-31TD-i is an expansion unit with the added benefit of time delayed contacts. It has been designed to connect to a standard VIPER SCR-i safety relay for extra time delayed output contacts to the end user.

  • Delayed contacts: 3NC 1NO (0-30 seconds)
  • Up to PLd, SIL 2, Category 3

Part NumberDescriptionInputsOutputsAuxiliarySupplyTerminals
280008SEU-31TD-i Screw Terminals 24V03 N/C Delayed (0-30s)1 N/O Delayed24Vac/dcScrew
280008-PSEU-31TD-i Pluggable Terminals 24V03 N/C Delayed (0-30s)1 N/O Delayed24Vac/dcPluggable

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

Power Supply Circuit
Rated operating voltage24V AC/DC
Operating voltage tolerance-15% - +10%
Rated supply frequency50Hz – 60Hz
Rated supply current100mA
Power consumption24V 2.5W

Control Circuits
Rated output voltageS11 24V DC
Input currentS15, S16 100mA
Response time100ms
Release time25ms
Recovery timeApprox. 1s
Time delay range0 - 30s

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
Rated insulation voltage250V
Degree of protectionIP20
Temperature range-20C + 55C
Degree of contamination2
Overvoltage categoryIII
MountingAny position
Time delay range0 – 30 Seconds