Performance of Surge Protection Device (SPD)

Normally, people pay a lot of attention on the performance of a surge protection device (SPD) like its surge capacity. Surge capacity is indeed very important. There are too many surge protection devices (SPDs) on the market can not meet the surge capacity it proclaimed. Here is a picture and video of a SPD that exploded at surge current test (Imax 40kA):

low quality surge protection device exploded

Safety of Surge Protection Device (SPD)

Yet few attention is paid on the safety of a surge protection device. However, bad designed SPD can be extremely dangerous and is one of the major causes for fire hazard. Below is some burnt SPD pictures:

UL Warns of Potentially Hazardous Surge Protectors

NORTHBROOK, Ill., July 29, 2016 — The following is a notification from UL that the surge protectors identified below may pose a fire hazard. The product does not comply with UL’s Safety Standards and is not authorized to bear the UL Mark for the United States or Canada.

ABC News Report - Warning for homeowners: Home-protection device could actually cause a fire

CARY, N.C. (WTVD) — The Cary Fire Department is warning homeowners following the fifth fire connected to a surge protector in the town during the past four years.

“We started kind of seeing these types of fires that occurred, specifically one that had some significant damage to a home. A fire that traveled up the vinyl siding of a home, and then eventually into the attic space, and eventually into the roof,” explained Cary FD Capt. Scott Benninghoff.

SPD/MOV is the Victim of Temporary Overvoltage (TOV)

SPDs not properly designed or incorrectly used and unprotected MOVs may go into thermal runaway, resulting in short circuit, overheating, smoke and potentially fire hazard due to:

End of life
Sustained abnormal overvoltage / Temporary Overvoltage (TOV)
Surge with unexpected energy

MOV or SPD are protectors of Transient Overvoltage (or surge) but victims of Temporary Overvoltage.

MOV Burnt Under Temporary Overvoltage (TOV)

MOV Burnt Under Temporary Overvoltage (TOV)

Temporary Overvoltage VS Transient Overvoltage

	Temporary Overvoltage (TOV)	Transient Overvoltage
Caused by	LV/HV-system faults	lightning or switching overvoltage
Duration	Long millisecond to a few minutes or hours	Short Microseconds (lightning) or millisecond (switching)
MOV status	Thermal runaway	Self-recovery

TOV is more destructive to SPD as its duration is much longer

Temporary Overvoltage is Common

temporary over-voltage on AC power line resulting from loss of neutral

TOV is a very common problem in power quality

Surge Protection Device Safety Solution – TPAE Technology

Prosurge has developed TPAE (Thermally Protected Arc Extinguishing) technology to solve the safety problem of SPD and we’ve got this technology patented in USA, Germany, Korea and China.

Patent in USA

Patent in Germany

Patent in Korea

Patent in China

Based on TPAE technology, we have developed our key SPD component – SMTMOV and PTMOV.

SMTMOV

PTMOV

You can see how our product stay safe in a sustained overvoltage situtation while our competitor’s product burnt.

At 415Vac temporary overvoltage, our SMTMOV with TAPE technology cuts itself off this abnormal condition and stays safe

At 415Vac temporary overvoltage, SPD component without TPAE technology burnt badly.

In below test, the two SPDs are tested under TOV(transient overvoltage). See how the result differs for SPD with TPAE protection and SPD without TPAE protection:

With Prosurge patented TPAE technology, the SPD is fail-safe and self-protected.

Without arc extinguished device, the SPD causes smoke and fire, which will be dangerous to the circuit.

Maximum Safety in Surge Protection

Thermally Protected MOV

AC DIN-rail Surge Protection Device

DC DIN-rail Surge Protection Device

UL 1449 Panel Surge Protection Device