Most of us have used the X10 XPPF plug-in filter to isolate signal suckers or noise generators. That is a very good low-pass filter, but it becomes warm when pushed near its 5 amp rating. The higher current filters available from SmartHome and ACT are narrow-band notch filters. They are effective at the X10 bandpass, but can allow noise outside that bandpass to leak through. As a result, a particularly strong noise source outside the X10 bandpass can still cause problems.
The XTB-F10 and XTB-F15 are alternate high-current filters. While they have similar topology to the SmartHome and ACT filters, their values were selected to provide a much wider rejection band so they behave much more like the XPPF low-pass filter. The XTB-F10 and XTB-F15 can be effective isolating even very strong noise sources outside the X10 bandpass.
One might think that the higher current XTB-F15 would be the best overall choice, but that is not the case. The higher current rating dictates lower value inductors, resulting in a narrower rejection band and slightly more signal loading. While still better than the other available high-current filters, its rejection isn’t as broadband as the XTB-F10. So the XTB-F10 is the best all-around filter, and the XTB-F15 should be used for those very high current loads that require the 15 amp rating.
The XTB-F15+ is an enhanced high-current filter. It also has a 15 amp current rating, but it is almost as good as the XTB-F10 at isolating a noise generator.
While the XTB-F10 and XTB-F15 are no longer available, a limited number of the XTB-F15+ are available.