Simply Automated Noise Filter, UPB

The Noise Filter - Isolator, model ZNF, is used to reduce or eliminate noise or attenuating devices that interferes with the transmission of UPB signals. Switching power supplies and other devices that run at frequencies between 4-40 kHz may interfere with UPB signals.

The ZNF Noise Filter - Isolators are installed between the UPB device or Line and the noise or attenuating source. They block noise above 4 kHz and should be compatible with all power line technologies. They can also be used to block the attenuating effect of highly capacitive devices, such as Uninterruptible Power Supplies (UPS).