The Rain Bird LSP-1 is a line surge protector for 2-wire path systems and must be installed and grounded every 500 feet (150 metres) and at the end of a decoder wire run. A Decoder System 2-wire path must be properly surge protected and grounded. Doing so can help prevent damage to the decoders and irrigation system and also significantly reduce troubleshooting, repair time and expense Resistance of the two-wire path to ground must be no greater than 50 Ohms.