Phoenix Contact 2906797 A surge protection solution comprises a protective plug and base element that incorporates a status indicator and knife-disconnection mechanism for three signal wires with a common reference potential. Suitable for high-frequency applications and telecommunications interfaces where no power supply voltage is present, it features indirect grounding via a gas discharge tube, meeting the requirements of EX e approval for zone 2, and is compatible with HART protocols. Additionally, it can be utilized in safety-critical circuits up to SIL 3 level of reliability.