On Friday, May 20, 2016 at 5:48:30 PM UTC-4, Uncle Monster wrote:
Every modern electronic device that plugs into a wall outlet
that I've had apart, has 1 or more MOV's on the 120vac line in.


Again, protection is provided by how the entire thing works. We may add MOVs (or other devices such as avalanche diodes) to supplement that already robust protection. As I have been saying all along - and trader does not want to read it. Many appliances stopped adding MOV to still have robust internal protection. For example, Apple II once used MOVs. Later Apple stopped because better protection that is part of a PSU design made those MOVs irrelevant.

Why does he find MOVs in appliances? Because all appliance must already have robust protection. So MOVs are added to even increase that protection.

MOV only protect from metallic mode currents. Protection from other destructive currents is performed by other parts already inside each appliance. Best protection from those other surges is already inside electronics - with or without MOVs. MOVs may supplement robust protection that is already inside all electronics. But that protection exists even without MOVs.

Effective 'whole house' protection is installed so that robust internal protection inside appliances is not overwhelmed by something that might occur once every seven years.

With or without MOVs, all appliances still have robust protection provided by how other parts are designed. Trader intentionally misrepresents that to argue incessantly for egotistical gratification.