Open it up and look. Should be 3 varistors, line to line and 2 as line to ground. and all three behind the switch so nothing is clamped if the switch is off.
Should also mention that the spike protection disappears after a certain number and strength of spikes. Generally strips should be assumed to be used up after a year, no later than 2 years. But this is also dependent on how good the power is, what is also connected to the power, and how many thunderstorms with lightning occur.
I never hear any discussion of this but I know it happens. Ed Fair
efair@atlnet.com
Any advice I give is my best judgement based on my interpretation of the facts you supply.
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