NTC 5D-20 Circuit Protection Thermistors Resistance 5 ? ± 20% Max Steady State Current 7.0 A Size: 20mm diameter, 4.8mm width, 10mm lead spacing The 5D-20 Power NTC Thermistors provide inrush current suppression for sensitive electronics. Connecting a 5D-20 in series with the power source will limit the current surges typically created at turn on. Once the circuit is energized the resistance of the 5D-20 will decrease rapidly to a very low value, power consumption can be ignored and there will be no effect on normal operating current. Using the 5D-20 Power NTC Thermistor is a most cost-effective way to curb surge current and protect sensitive electronics from damage.