And thanks for the thread, Eric. A real public service.
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.
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@terry9 Isolation transformers have a lot of inductance, they act a little like series mode protectors. :) |
@carlsbad2 Depends on how you classify them. Some statistics say 80% or more come from inside, especially whenever inductive loads (i.e. big motors) start or stop. Of course, this includes very small surges we might expect equipment to shrug off. They tend to be small, but may accumulate. Anyone who has ever heard a thump through their stereo when a vacuum, ceiling fan, AC or hair dryer has turned on or off has literally heard a surge. |
Awww, thanks @terry9 |
@carlsbad2 Sorry I didn’t really answer your question. As I understand it, the most common cause of a surge inside the home is when a large inductive load (motor) is turned off. The magnetic field has inertia and until it collapses is present and the motor tries to feed that energy back into the system. This is the best description I've found:
https://forums.mikeholt.com/threads/can-a-vacuum-cleaner-cause-a-surge.60537/ |
- 71 posts total