Littelfuse KRDS221 is an encapsulated time-delay relay with a male quick connect termination. It has an output load rating of 10 A resistive @ 125 V ac, 5 A resistive @ 230 V ac and 28 V dc, and 1/4 hp @ 125 V ac. It operates on an input AC line frequency of 50/60 Hz with a tolerance range of -15% to 20%. The relay has a repeat accuracy of ±0.5% or 20 ms, insulation resistance of ≥100, and a setpoint vs ambient temperature and operating voltage tolerance of ≤±5%. It has a power consumption of ≤2 VA (AC) and ≤2 W (DC), a time delay tolerance of ≤±5%, and a reset time of ≤150 ms. The time delay type is microcontroller with watchdog circuitry. The KRDS221 has a life expectancy of 1 x 10⁵ electrical cycles and 1 x 10⁷ mechanical cycles. It features a quick initiate time of ≤40 ms and is reverse polarity protected for DC units. The input DC ripple is ≤10%.