Why whole house surge protectors are not enough


TL;DR:

One measure of a surge protector is the clamping voltage. That is, at what voltage does the surge protector actually start to work. Whole house surge protectors are limited to no less than ~ 600 Volts (instantaneous) between a leg and neutral or ground. That’s up to 1,200V if symmetrical.

The best surge protecting strips and conditioners clamp below 200 Volts.

Please keep this in mind when deciding whether or not to use surge protectors at your PC, stereo, TV, etc. in addition to a whole house unit.

I wrote more about this here:

 

https://inatinear.blogspot.com/2021/09/time-for-new-surge-suppression.html

No manufacturer of whole house surge protection claims that their devices alone are enough for sensitive electronics when you check the fine print.

erik_squires

Caelin Gabriel and Shunyata make suppressors for medical gear so I think they're a lot more knowledgeable than most people here.

 

Than most people here is not setting a very high bar but even then I am not sure. They say a lot of dumb stuff.

150 vrms. They use 140v MOV probably. Not doing anything till 240 DC. A big surge is going to be over 400V.  The datasheets don't give a lot of details. 

What's the controversy?  Whole house plus a power bar for surge protection. Seems pretty obvious. MOVs don't do anything to your audio. Crazy to believe they do.

 

The article I referenced in my blog has the only independent survey if surge protector performance I know of.  Furman and Tripp Lite measured among the best with the lowest measured let through voltages.

Interested in protecting your outdoor A/C condenser from power surges and brownouts? This package looks to be one of the best I've ever seen:

RSH-50 VRM KIT

@dpop I've never seen over/undervoltage protection for residential AC units, so that is pretty cool. I hope it's not extravagantly expensive.

We do see AC unit surge protectors around here though.

@erik_squires Around $250. I’ve just recently discovered these, and plan on installing one on my condenser.

I also have these on my humidifier, dehumidifier, refrigerator and furnace (i.e., any device I own that has a motor or compressor), even though I rarely ever experience brownouts (you never know though when they might pop up). I like to be proactive (some may call it OCD). This also looks to have one of the lowest *specified* clamping voltages (140 V) I’ve ever seen on a surge protector. Even though I already incorporate a ton of surge protection in my house, and on my video and audio gear, I may even consider adding one of these to the audio and video (non power amp) AC feed for this gear:

Heavy Duty 20-Amp 2400-Watt Appliance Surge Protector