SG420

Inrush Current Limiters (ICL) Overview

The SG420 is a SURGE-GARD inrush current limiter manufactured by Vishay Ametherm. It utilizes NTC thermistor technology to suppress high initial currents during power-up. The component features a radial leaded package designed for PCB mounting. Key electrical specifications include a nominal resistance of 2 Ohms with a tolerance of ±25%. It supports a maximum steady-state current rating of 23 A and operates at voltage ratings up to 265 VAC. Physical dimensions include a diameter of 1.250 inches (31.75 mm). The device is UL approved, ensuring compliance with safety standards for electronic equipment applications.

Inrush Current Limiters (ICL) Feature Summary

• NTC thermistor construction for effective inrush current suppression
• UL approved for enhanced safety compliance
• Radial leaded design optimized for PCB mounting

Inrush Current Limiters (ICL) Applications

• Power supply input stages
• Electronic ballast circuits
• Motor drive protection

Inrush Current Limiters (ICL) Procurement Notes

Verify the specific ordering suffix against the official Vishay datasheet to ensure correct tolerance and lead configuration. Confirm that the 23 A current rating aligns with the thermal management requirements of the target application. Check for RoHS compliance status if environmental regulations apply. Ensure the 265 VAC rating exceeds the peak line voltage present in the circuit design.

Inrush Current Limiters (ICL) Selection Notes

Select this component when a low nominal resistance of 2 Ohms is required to minimize steady-state power dissipation while handling high peak currents up to 23 A. The large physical diameter facilitates heat dissipation in high-power scenarios. Consider the radial package style for through-hole assembly processes. Validate that the operating temperature range meets the environmental conditions of the installation site.

Inrush Current Limiters (ICL) Part Context

The SG420 belongs to the SURGE-GARD series of inrush current limiters produced by Vishay Ametherm. This series is widely recognized for providing reliable protection against capacitive charging spikes in various power electronics. The SG model designation typically indicates standard radial leaded configurations suitable for general-purpose industrial and commercial power supplies.

Inrush Current Limiters (ICL) Replacement Considerations

Cross-reference with other Vishay SG series parts or equivalent NTC thermistors from manufacturers like EPCOS or Murata. Ensure substitute components match the 2 Ohm resistance, 23 A current rating, and 265 VAC voltage rating. Verify physical footprint compatibility for PCB mounting.