Surge protector
I know the best kind are the ones which would be wired into the system, but saw this today and wondered if it would be any good. Is this a "better than nothing" or "you get what you pay for" situation...
Forum Discussion
rbpru wrote:
Okay thanks, that is what I wanted to know. If a surge pops the MOVs, the unit will no longer work.
MOVs can pop. Progressive protective functions still operate.
MOVs (even in completely different devices called protectors) must never pop. That is an unacceptable (catastrophic) failure even described on page one of MOV datasheets. MOVs must be designed into a protector so that MOVs disconnect; and all other items (protector circuits, interior appliances, etc) remain connected to AC power.
Described are MOVs that will only absorb 360 joules and never more than 720 joules. All appliances make such tiny surges irrelevant. Protection inside every appliance is more robust. Those joules are doing near zero protection - especially from potentially destructive surges that can be tens or hundreds of thousands of joules. But that is a rare anomaly. How often is a home dishwasher and dimmer switches replaced every year?
Reverse polarity can even be reported by a $6 three light tester. Floating ground may also be detected. But let's be clear about this. That tester can only report defects. It cannot report good wiring. And it can do nothing (fast enough) to avert damage.
Faults that cause concern can happen at any time. A Progressive, et al type protector will (must) disconnect fast enough to avert damage. And remain disconnected until the anomaly is corrected. No manual testers can perform that essential function.
Nothing can disconnect from lightning (and other similar anomalies) fast enough. But those anomalies are quite rare. Frequent type anomalies are what Progressive, et al devices protect from - by disconnecting AC power.
