Frequently Asked Questions
What is the difference between transient surge and temporary overvoltage (TOV)?
A transient surge is a very short voltage spike (microseconds to milliseconds), while TOV is a sustained overvoltage lasting seconds to minutes. SPDs handle surges well but can fail under TOV.
Why do standard SPDs fail under TOV conditions?
Under TOV, the MOV remains conductive for an extended period, causing rapid heat buildup and thermal runaway, which can lead to smoke, fire, or device failure.
How does Eprotek's TPAE technology improve SPD safety?
TPAE (Thermally Protected Arc Extinguishing) technology uses a patented arc-extinguishing thermal disconnector to rapidly cut off the circuit, preventing continuous overheating and eliminating fire risk.
Are SPDs designed to protect against TOV?
No, SPDs are primarily designed for transient overvoltage, not TOV. UL 1449 ensures safety under TOV but does not guarantee protection.
What should I look for when selecting a safe SPD?
Choose SPDs with thermal protection mechanisms like TPAE, compliance with UL 1449 5th Edition, and suitability for your specific system conditions.
