MS350R550

Inrush Current Limiters (ICL) Overview

The MS350R550 is a negative temperature coefficient (NTC) thermistor from the Vishay Ametherm MegaSurge MS35 series, designed as an inrush current limiter. It features a radial leaded package with a 37 mm diameter and 19 mm lead spacing. The component has a nominal resistance of 0.5 Ohms at 25 °C with a tolerance of ±25%. It supports steady-state currents up to 50 A and is rated for AC voltages of 120 VAC, 240 VAC, 480 VAC, and 680 VAC. The unit weighs approximately 21.5 g.

Inrush Current Limiters (ICL) Feature Summary

• Provides simple one-component protection against high initial charging currents in power supply circuits.
• Utilizes NTC characteristics to offer low resistance during normal operation after initial thermal heating.
• Radial PCB mount construction facilitates straightforward integration into standard assembly processes.

Inrush Current Limiters (ICL) Applications

• Power supply input stages
• Transformer primary windings
• Capacitor bank charging circuits

Inrush Current Limiters (ICL) Procurement Notes

Verify that the specific application voltage does not exceed the maximum ratings of 680 VAC. Confirm that the expected steady-state operating current remains within the 50 A limit to prevent thermal damage. Ensure the PCB layout accommodates the 37 mm body diameter and 19 mm lead pitch. Check RoHS compliance status if required by the final product specifications.

Inrush Current Limiters (ICL) Selection Notes

Select this component when a low resistance value of 0.5 Ohms is required to limit peak inrush currents effectively. The 50 A current rating makes it suitable for higher power applications compared to lower-rated variants. Consider the physical dimensions and radial lead configuration for mechanical fitment on the target printed circuit board.

Inrush Current Limiters (ICL) Part Context

This part belongs to the MegaSurge MS35 series of inrush current limiters manufactured by Vishay / Ametherm. The series offers various resistance and current combinations to suit different power levels. These components serve as alternatives to complex relay-based or resistor-bypass solutions.

Inrush Current Limiters (ICL) Replacement Considerations

Direct substitutes include other Vishay Ametherm MS35 series parts with matching electrical parameters. Verify that any replacement maintains the same 0.5 Ohm resistance and 50 A current rating. Ensure the physical footprint and lead spacing are compatible with existing PCB layouts.