Reed Relay Protection
The life expectancy of a reed relay can be greatly affected by the nature of the load. To prolong the life of reed relays, consider the following list when using switches with reed relays:
- Bounce
- Arcing
- Capacitance
- Inrush Current
- Inrush Current Protection
- Board Layout and Topology
- Example System
In general, reed relays are vulnerable to contact welding from high currents. Parasitic capacitance within a system can unavoidably create high inrush currents that can damage the reed relay. To minimize inrush current, decrease or isolate external capacitance by:
- Using lower switching voltages.
- Avoiding large capacitive loads to the switch.
- Isolating external capacitance with series impedance Rp such that:
V/Rp< switching current rating of the relay