Protech by Hirsch presents the REF-1 RFI/EMI Power Line Filter is an essential accessory for PIRAMID dual-technology sensors deployed in electrically hostile environments where radio frequency interference (RFI) and electromagnetic interference (EMI) can compromise sensor performance. Designed for 1/2-inch conduit installations, this inline filter effectively suppresses conducted noise on the DC power line - preventing false alarms and signal degradation caused by high-voltage equipment, transformers, switchgear, and arc flash events commonly found at power substations, electrical utilities, and industrial facilities. By filtering EMI/RFI before it reaches the sensor's electronics, the REF-1 ensures stable, nuisance-free operation of your PIRAMID XL, XL2, XL3, MIL, HS, EX, and DIR series sensors in even the most demanding electromagnetic environments. Protect your high-security perimeter investment with this critical power conditioning accessory from Protech.