Originally Posted by Rolling buckeye
I think, the high or low voltage,from cg pedestal,and possibly the same from gen set,not much can do with lighting.
First, your local telco has a $multi-million computer connected to wires all over town. May suffer about 100 surges with each thunderstorm. How often is your town without phone service for four days after every storm while they replace that computer? Never? Exactly. Because well proven solutions have existed for over 100 years to make damage from lightning irrelevant.
However, many spent big bucks on some products, suffered damage, then only assumed nothing can protect from lightning. Rather than learn that those products never claimed to do that protection. Learned of other, well proven, and less expensive solutions.
Second, high or low voltage? What is high and what is low - in numbers? Well, let's put numbers to some anomalies hoping that a still undefined anomaly is what you want to avert. BTW high voltages are completely different from lightning.
High voltages can increase to 150 or to something less than 240 volts due to failures such as an open or failing neutral. An anomaly that a Progressive (or equivalent device) claims to protect from. To disconnect from AC mains when that voltage rises too high.
What is at greatest risk? Motorized appliances (refrigerator, air conditioner). Utilities must keep 120 volts so regulated that your AC mains will not rise above 130 volts. To protect appliances at most risk - motorized appliances. Electronics tend to be more robust. In particular portable electronics whose normal voltage is anywhere from 85 to 265 VAC.
Is voltage going too high? Sometimes obvious by observing an incandescent bulb increasing light intensity. An incandescent bulb is a superb tool to identify this anomaly that is, unfortunately, too common in some campgrounds.
Power strip protectors remains inert - do nothing - until voltages rise above 330 volts. A number printed on each box. And an example of what is always required - the numbers. High voltage (maybe 150 or 220 volts) would be completely ignored by a power strip protector. A power strip and the Progressive are two completely different devices that, unfortunately, share a common name.
High voltage - only in that voltage range - is one anomaly.
Third, low voltage is how low? Low voltage can put motorized appliances at risk. So a utility must either regulate line voltage or disconnect power. Unfortunately, low voltage without disconnecting power may exist in some campgrounds.
A dimming incandescent bulb is an ideal tool for identifying that anomaly. The Progressive can avert low voltage (which is not a surge) by disconnecting. Do your bulbs at all campgrounds never dim? Then that anomaly is not a concern.
Some more expensive units can compensate for voltages (the second and third anomalies) by adjusting voltages by as much as 10% or 20%. Another solution to those campground anomalies.
Minor low voltage can be harmful to motorized appliances. That same voltage (ie when a bulb dims to 50% intensity) is ideal and sufficient voltage to all electronics. Electronics must work just fine even at that low voltage. Or simply shut off normally should voltage go even lower. Low voltage is never destructive to properly designed electronics.
How often do incandescent bulbs indicate high or low voltages? That suggests the need for a Progressive or equivalent.
Fourth, another discussed MOVs failing frequently when used to avert generator spikes (on a ship). A least expensive solution is to always spend a little more for the better generator that does not generate such spikes. Best solution is always inside the generator. That properly regulates voltages even when a major appliance (ie air conditioner) suddenly powers off. Due to superior design, Honda is one example.
MOVs are not designed for continuous and tiny spikes from something like a generator.
Meanwhile, all electronics (long before the IBM PC existed) were required to make such spikes irrelevant. But that sentence did not provide numbers. 120 volt electronics must not be harmed by spikes of up to 600 volts. A typical UPS can output spikes exceeding 250 volts when providing power from an internal battery. All electronics make typically 'dirty' power from a UPS irrelevant due to existing and internal protection.
All appliances contain significant protection. Your concern are rare anomalies that can overwhelm that protection. The Progressive is one solution for some anomalies such as high and low voltages; as defined by above numbers. Not discussed is protection from other typically problematic anomalies (ie lightning).