The following actual oscillograms dramatically demonstrate the superior surge suppression of WVR and TSC filters when compared with conventional surge suppressors.

For optimum protection from surges and noise, the goal is to keep the surge energy from exceeding the normal power wave region. The following oscillograms clearly show that WVR and TSC filters are far more effective at restricting unwanted surge let-through energy (it is not just the voltage but also the duration that is important- hence our focus is on energy rather than merely voltage).

The TSC filter keeps the surge energy entirely within the normal power wave region, while the WVR filter allows a small amount of energy lasting only 20 microseconds, compared with surge suppressors which let through greater energy lasting over 35 microseconds in the positive direction and over 100 microseconds in the negative direction!

WVR and TSC filters are not required to have "protection working" indicators since there is no history of failures or fires, or other safety related problems with filters.