Thanks again, ame.
I find this discussion interesting and informative. After additional research, I found several protection safeguards that can be employed with relays. Each has their own purpose and physical location within the circuit. pidd may find this useful as well considering the issue he is experiencing.
ame, the protection you are talking about (driver protection) I believe falls into case #1. I am researching what additional protections are needed for my use cases. I am making relay circuits with both ac and dc drivers. Each will have their own set of protection safeguards. I will document my thoughts on each of those soon.
1. Flyback Diode (Freewheeling Diode):
Function: Protects against voltage spikes and back electromotive force (EMF) generated when the relay coil's magnetic field collapses.
Location: Connect in parallel with the relay coil terminals.
2. Snubber Circuit:
Function: Reduces voltage transients and minimizes arcing across the relay contacts during opening or closing.
Location: Connect in parallel with the relay contacts.
3. Overcurrent Protection:
Function: Protects the relay and connected components from excessive current flow that could lead to overheating and damage.
Implementation: Use fuses, circuit breakers, or current-limiting resistors.
4. Isolation (For High Voltage):
Function: Provides electrical isolation between the control (driver) side and the load side of the relay, protecting the control circuit from high voltages on the load side.
Implementation: Optocouplers, solid-state relays, or physical isolation.
5. Transient Voltage Suppressors (TVS):
Function: Protects against transient voltage spikes and surges that could damage the relay.
Location: Connect in parallel with the relay coil or contacts.
6. Varistor (MOV - Metal Oxide Varistor):
Function: Protects against voltage surges and transients.
Location: Connect in parallel with the relay contacts.
7. Damping Resistor:
Function: Reduces contact bounce and minimizes wear on the relay contacts.
Location: Connect in series with the relay coil.
8. Overvoltage Protection:
Function: Guards against voltage levels above the relay's specified rating.
Implementation: Varistors, Zener diodes, or voltage clamping devices.
9. Thermal Protection:
Function: Monitors the temperature of the relay to prevent overheating.
Implementation: Thermal cutoffs, thermal switches, or temperature sensors.
10. Voltage Regulation (if needed):
Function: Maintains a stable voltage supply to the relay, ensuring proper operation.
Implementation: Voltage regulators.
11. Grounding:
Function: Ensures proper grounding to prevent electrical noise and interference.
Implementation: Connect the relay and associated components to a reliable ground.
12. Proper Load Matching:
Function: Ensure that the relay is matched with the appropriate load to prevent excessive current flow and contact damage.
Consideration: Match the relay's contact ratings with the load requirements.
I find this discussion interesting and informative. After additional research, I found several protection safeguards that can be employed with relays. Each has their own purpose and physical location within the circuit. pidd may find this useful as well considering the issue he is experiencing.
ame, the protection you are talking about (driver protection) I believe falls into case #1. I am researching what additional protections are needed for my use cases. I am making relay circuits with both ac and dc drivers. Each will have their own set of protection safeguards. I will document my thoughts on each of those soon.
1. Flyback Diode (Freewheeling Diode):
Function: Protects against voltage spikes and back electromotive force (EMF) generated when the relay coil's magnetic field collapses.
Location: Connect in parallel with the relay coil terminals.
2. Snubber Circuit:
Function: Reduces voltage transients and minimizes arcing across the relay contacts during opening or closing.
Location: Connect in parallel with the relay contacts.
3. Overcurrent Protection:
Function: Protects the relay and connected components from excessive current flow that could lead to overheating and damage.
Implementation: Use fuses, circuit breakers, or current-limiting resistors.
4. Isolation (For High Voltage):
Function: Provides electrical isolation between the control (driver) side and the load side of the relay, protecting the control circuit from high voltages on the load side.
Implementation: Optocouplers, solid-state relays, or physical isolation.
5. Transient Voltage Suppressors (TVS):
Function: Protects against transient voltage spikes and surges that could damage the relay.
Location: Connect in parallel with the relay coil or contacts.
6. Varistor (MOV - Metal Oxide Varistor):
Function: Protects against voltage surges and transients.
Location: Connect in parallel with the relay contacts.
7. Damping Resistor:
Function: Reduces contact bounce and minimizes wear on the relay contacts.
Location: Connect in series with the relay coil.
8. Overvoltage Protection:
Function: Guards against voltage levels above the relay's specified rating.
Implementation: Varistors, Zener diodes, or voltage clamping devices.
9. Thermal Protection:
Function: Monitors the temperature of the relay to prevent overheating.
Implementation: Thermal cutoffs, thermal switches, or temperature sensors.
10. Voltage Regulation (if needed):
Function: Maintains a stable voltage supply to the relay, ensuring proper operation.
Implementation: Voltage regulators.
11. Grounding:
Function: Ensures proper grounding to prevent electrical noise and interference.
Implementation: Connect the relay and associated components to a reliable ground.
12. Proper Load Matching:
Function: Ensure that the relay is matched with the appropriate load to prevent excessive current flow and contact damage.
Consideration: Match the relay's contact ratings with the load requirements.
Statistics: Posted by LoganRoy — Fri Jan 19, 2024 2:53 pm