Recently I had a summer lighting storm that fried an older computer. I had it hooked up to a surge protector and thought I would be ok.
After this incident, I decided it was time to upgrade the surge protector. Well, researching replacements I found it was more difficult than just buying an inexpensive one off Amazon.
Most surge protectors only have a lifespan of 3 to 5 years. The worse thing is most also continue to pass electricity through even after the protection aspect no longer works.
Here is some basic information about how a MOV protector work.
Surge protectors are generally rated according to the amount of energy in joules they can absorb. The Joule rating number defines how much energy a MOV-based surge protector can theoretically absorb in a single event, without failure. Better protectors exceed ratings of 1,000 joules and 40,000 amperes. Since the actual duration of a spike is only about 10 microseconds the actual dissipated power is low. Any more than that and the MOV will fuse, or sometimes short and melt, hopefully blowing a fuse, disconnecting itself from the circuit.
The MOV (or other shorting devices) requires resistance in the supply line to limit the voltage. For large, low resistance power lines a higher joule rated MOV is required. Inside a house, with smaller wires that have more resistance, a smaller MOV is acceptable.
Every time a MOV shorts, its internal structure is changed and its threshold voltage is reduced slightly. After many spikes, the threshold voltage can reduce enough to be near the line voltage, i.e. 120 vac or 240 vac. At this point, the MOV will partially conduct and heat up and eventually fail, sometimes in a dramatic meltdown or even a fire. Most modern surge protectors have circuit breakers and temperature fuses to prevent serious consequences.
Clamping voltage
In addition to joules, there is also a clamping voltage aspect. Also known as the let-through voltage, this specifies what spike voltage will cause the protective components inside a surge protector to short or clamp. A lower clamping voltage indicates better protection, but can sometimes result in a shorter life expectancy for the overall protective system. The lowest three levels of protection defined in the UL rating are 330 V, 400 V, and 500 V. The standard let-through voltage for 120 V AC devices is 330 volts.
Response Time
The response time is how long it takes for the surge protector to detect a surge in electricity. A lower value means a faster response. This reduces the time that your plugged-in devices are exposed to the surge, thus protecting them better. Ideally, you'll want a surge protector with a response time of 1 nanosecond or faster.
Now with a basic understanding of how MOV surge protectors work, what is a good choice to protect our audio equipment? Here I ran into tons of confusing info on this subject. Things like how the extra circuits affect sound quality? Are surge protectors needed in modern equipment since some have fused and built-in protection. Reports of some greatly improve sound quality whereas others ruin it.
Being far from an expert it seemed the more I read on the subject the more I became frustrated with what was the best option.
I ended up with the Furman PST-8 Sound Power Station Series. The reason I went with it where the first price. I wanted to limit spending to around $100.00 and felt it was the best unit in this price range. I also wanted something that wouldn’t wear out like the normal MOV protection. I feel like one using SMP, LiFT, and EVS makes more sense.
Below is some information from Furman that helped me decide on this product and explains in more detail what SMP, LiFT and EVS terms mean.
The PST-8 all features Furman’s SMP circuit which incorporates Linear Filtering Technology (LiFT) and a high current TVZ-MOV to ensure that any electronic device (including televisions, projectors, CD-DVD players, or computers) is fed clean, filtered AC power. This dramatically reduces noise, ensuring consistent peak performance from your equipment.
Typical AC filters feature antiquated non-linear circuits. Though these multiple-stage filters or power cleaners reduce some noise, they do so unevenly. They can add noise to your power line due to their filter’s excessive resonant peaking. With Furman’s proprietary Linear Filtering Technology (LiFT), AC noise is suppressed evenly, assuring maximum performance from your system.
Additionally, today’s power grid commonly experiences numerous electrical surges and spikes daily. At best, these irregularities can degrade your equipment’s performance, and, at worst, can severely damage your entire system. Furman’s SMP circuit offers the highest degree of protection available without sacrificing itself or any of its components.
Conventional AC conditioners employing older technologies leak voltage to circuit ground which can, in fact, aid in damaging sensitive digital circuits such as computer processors. Furman’s new technology, however, never directs voltage to the circuit ground further ensuring the safety of your equipment.
Another feature that is unique to Furman’s SMP circuit is automatic extreme-voltage shutdown. Extreme voltages are statistically the most common, damaging AC event. The Extreme Voltage Shutdown circuit automatically turns off the unit when it is fed 137 volts or higher protecting itself and connected equipment from the extreme voltage. Only Furman offers this degree of protection! Add telco and cable /satellite transient voltage suppression, and you have what is, unquestionably, the most comprehensive protection available in a portable AC power conditioner.
After this incident, I decided it was time to upgrade the surge protector. Well, researching replacements I found it was more difficult than just buying an inexpensive one off Amazon.
Most surge protectors only have a lifespan of 3 to 5 years. The worse thing is most also continue to pass electricity through even after the protection aspect no longer works.
Here is some basic information about how a MOV protector work.
Surge protectors are generally rated according to the amount of energy in joules they can absorb. The Joule rating number defines how much energy a MOV-based surge protector can theoretically absorb in a single event, without failure. Better protectors exceed ratings of 1,000 joules and 40,000 amperes. Since the actual duration of a spike is only about 10 microseconds the actual dissipated power is low. Any more than that and the MOV will fuse, or sometimes short and melt, hopefully blowing a fuse, disconnecting itself from the circuit.
The MOV (or other shorting devices) requires resistance in the supply line to limit the voltage. For large, low resistance power lines a higher joule rated MOV is required. Inside a house, with smaller wires that have more resistance, a smaller MOV is acceptable.
Every time a MOV shorts, its internal structure is changed and its threshold voltage is reduced slightly. After many spikes, the threshold voltage can reduce enough to be near the line voltage, i.e. 120 vac or 240 vac. At this point, the MOV will partially conduct and heat up and eventually fail, sometimes in a dramatic meltdown or even a fire. Most modern surge protectors have circuit breakers and temperature fuses to prevent serious consequences.
Clamping voltage
In addition to joules, there is also a clamping voltage aspect. Also known as the let-through voltage, this specifies what spike voltage will cause the protective components inside a surge protector to short or clamp. A lower clamping voltage indicates better protection, but can sometimes result in a shorter life expectancy for the overall protective system. The lowest three levels of protection defined in the UL rating are 330 V, 400 V, and 500 V. The standard let-through voltage for 120 V AC devices is 330 volts.
Response Time
The response time is how long it takes for the surge protector to detect a surge in electricity. A lower value means a faster response. This reduces the time that your plugged-in devices are exposed to the surge, thus protecting them better. Ideally, you'll want a surge protector with a response time of 1 nanosecond or faster.
Now with a basic understanding of how MOV surge protectors work, what is a good choice to protect our audio equipment? Here I ran into tons of confusing info on this subject. Things like how the extra circuits affect sound quality? Are surge protectors needed in modern equipment since some have fused and built-in protection. Reports of some greatly improve sound quality whereas others ruin it.
Being far from an expert it seemed the more I read on the subject the more I became frustrated with what was the best option.
I ended up with the Furman PST-8 Sound Power Station Series. The reason I went with it where the first price. I wanted to limit spending to around $100.00 and felt it was the best unit in this price range. I also wanted something that wouldn’t wear out like the normal MOV protection. I feel like one using SMP, LiFT, and EVS makes more sense.
Below is some information from Furman that helped me decide on this product and explains in more detail what SMP, LiFT and EVS terms mean.
The PST-8 all features Furman’s SMP circuit which incorporates Linear Filtering Technology (LiFT) and a high current TVZ-MOV to ensure that any electronic device (including televisions, projectors, CD-DVD players, or computers) is fed clean, filtered AC power. This dramatically reduces noise, ensuring consistent peak performance from your equipment.
Typical AC filters feature antiquated non-linear circuits. Though these multiple-stage filters or power cleaners reduce some noise, they do so unevenly. They can add noise to your power line due to their filter’s excessive resonant peaking. With Furman’s proprietary Linear Filtering Technology (LiFT), AC noise is suppressed evenly, assuring maximum performance from your system.
Additionally, today’s power grid commonly experiences numerous electrical surges and spikes daily. At best, these irregularities can degrade your equipment’s performance, and, at worst, can severely damage your entire system. Furman’s SMP circuit offers the highest degree of protection available without sacrificing itself or any of its components.
Conventional AC conditioners employing older technologies leak voltage to circuit ground which can, in fact, aid in damaging sensitive digital circuits such as computer processors. Furman’s new technology, however, never directs voltage to the circuit ground further ensuring the safety of your equipment.
Another feature that is unique to Furman’s SMP circuit is automatic extreme-voltage shutdown. Extreme voltages are statistically the most common, damaging AC event. The Extreme Voltage Shutdown circuit automatically turns off the unit when it is fed 137 volts or higher protecting itself and connected equipment from the extreme voltage. Only Furman offers this degree of protection! Add telco and cable /satellite transient voltage suppression, and you have what is, unquestionably, the most comprehensive protection available in a portable AC power conditioner.
