Relay Calculator

Calculate relay coil requirements, flyback protection, and contact ratings.

Relay Specifications

Contact Circuit

Coil Requirements

30.0 mA
Coil Current
360 mW
Coil Power

Flyback Protection

Flyback Spike120 V
Clamped Voltage12.7 V

Use 1N4148 or 1N4007 flyback diode across coil

Contact Derating

Derating Factor100%
Effective Rating10.0 A
Switch Power1200 W

Timing

Pickup Voltage9.0 V
Dropout Voltage3.0 V
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Editorial Note

MyCalcBuddy Editorial Team

This page is maintained as an educational calculator reference.

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Formula Source: Standard Mathematical References

by Various

🔄Last reviewed: May 2026
✓Formula checks are based on standard references and internal QA review.