Signal SD-S Series Lightning Protection Modules for SDS Two-Wire Irrigation Controllers – SD-SP / SD-SA / SD-GR

The Signal SD-S Series Lightning Protection Modules provide a coordinated surge protection system for Signal SDS Series Two-Wire Irrigation Controllers and connected field devices. Designed to protect controller electronics, DataCoils™, decoders, and other equipment from electrical surges caused by nearby lightning strikes or power disturbances, the system combines controller-level protection, field surge suppression, and dedicated grounding hardware. The range includes the SD-SP Surge Protector for installation at the controller, the SD-SA Surge Arrestor for protection along extended two-wire paths, and the SD-GR Grounding Rod Kit for establishing a suitable earth connection. Suitable Applications Signal SDS-50 and SDS-100 two-wire irrigation systems Commercial landscape irrigation installations Agricultural and farm irrigation systems Sports fields and turf irrigation networks Municipal parks and public landscape systems Long-distance two-wire irrigation networks Sites exposed to lightning or electrical surge risk Protection of controllers, DataCoils™, field devices, and two-wire cabling New SDS installations requiring compliant surge and grounding protection Existing SDS systems requiring additional field surge suppression Key Specifications Product Name Signal SD-S Series Lightning Protection Modules Product Type Lightning and Electrical Surge Protection System for SDS Two-Wire Irrigation Controllers Compatible Controllers Signal SDS-50 and SDS-100 Available Modules SD-SP Surge Protector, SD-SA Surge Arrestor, and SD-GR Grounding Rod Kit Primary Application Protection of SDS Controllers, Two-Wire Paths, and Connected Field Devices from Electrical Surges SD-SP Function Controller-Level Surge Protection and Grounding SD-SP Installation Location At the Irrigation Controller, Positioned as Close as Practical to the Earth Stake SD-SP Supply Included with SDS-50 and SDS-100 Controllers SD-SP Warranty Requirement Required for Applicable SDS System Warranty Compliance SD-SA Function In-Field Surge Suppression for the Two-Wire Network SD-SA Recommended Spacing Approximately Every 300–400 m or Every 16 Valves Along the Two-Wire Path SD-GR Function Grounding Rod Kit for SD-SP and SD-SA Installations Recommended Ground Rod Length Minimum 2 m Ground Resistance Requirement ≤10 Ohms Grounding Cable Flat Braided Grounding Cable Recommended Connection Method Approved Waterproof Two-Wire Connectors Typical Field Installation Valve Boxes or Accessible Service Pits Available Variants SD-SP Surge Protector installed at the controller to help protect controller electronics and the power input from electrical surges. It must be connected to a suitable earth stake. SD-SA Field Surge Arrestor installed along the two-wire path to provide additional surge suppression for DataCoils™, field devices, and extended irrigation cabling. SD-GR Grounding Rod Kit designed to provide a suitable grounding point for SD-SP and SD-SA installations, with a minimum 2 m rod recommended. Features Provides coordinated lightning and electrical surge protection for Signal SDS two-wire irrigation systems Protects both controller electronics and connected field equipment SD-SP controller surge protector is supplied with SDS-50 and SDS-100 controllers SD-SP installation is required for applicable SDS system warranty protection SD-SA field surge arrestors provide additional protection along extended two-wire networks Recommended SD-SA spacing is approximately every 300–400 metres or every 16 valves Helps protect DataCoils™, field devices, and two-wire cabling against surge events SD-GR Grounding Rod Kit provides a dedicated grounding solution for compatible protection modules System requires a ground resistance of 10 Ohms or less for effective protection Flat braided grounding cable is recommended to provide a low-impedance connection to earth Approved waterproof connectors are required for field connections to SD-SA modules Field arrestors can be installed in valve boxes or accessible service pits for inspection and maintenance Modular design allows additional field protection to be added as the irrigation network expands Installation Guidelines Install the SD-SP surge protector at the irrigation controller and position it as close as practical to the grounding stake. Connect the SD-SP to a correctly installed earth system using suitable flat braided grounding cable. Install SD-SA surge arrestors approximately every 300–400 metres or after approximately 16 valves along the two-wire network. Use approved waterproof two-wire connectors when connecting SD-SA units in field locations. Install field surge arrestors inside valve boxes or accessible service pits where they can be inspected and serviced. Use the SD-GR or another suitable grounding system capable of achieving an earth resistance of 10 Ohms or less. A minimum 2 m grounding rod is recommended where site conditions allow. Benefits Controller Protection: The SD-SP helps protect valuable SDS controller electronics and power circuits from damaging electrical surges. Field Device Protection: SD-SA modules extend surge suppression into the two-wire network to help protect DataCoils™, wiring, and connected devices. Reduced Damage Risk: Properly installed surge and grounding protection can reduce the likelihood of widespread irrigation system damage following nearby lightning activity or power anomalies. Scalable Protection: Additional field surge arrestors can be installed as the two-wire network becomes longer or additional valves are added. Improved System Reliability: Distributed surge protection helps improve the resilience of large commercial and agricultural two-wire irrigation installations. Warranty Compliance: Correct installation of the required SD-SP protection helps satisfy applicable SDS system warranty requirements.