Data & Signal Surge Protection

Shop surge protection for data, communication, instrumentation and low-voltage signal circuits. These devices help limit transient voltage reaching sensitive control and communication equipment through connections that may not be protected by an AC power-line surge protective device.

Compare signal-line surge protectors by circuit type, operating voltage, connector or terminal configuration, number of protected conductors, signal frequency or data rate and grounding requirements. The protection device must be compatible with the normal electrical characteristics of the signal.

How to Select Data and Signal Surge Protection

Electrical transients can enter equipment through more than its main power connection. Communication cables, instrumentation wiring, remote sensors and other signal conductors can provide additional paths for surge energy to reach sensitive electronics.

Signal-line protection must be selected carefully because the protective device becomes part of the communication or instrumentation circuit. Incorrect operating voltage, capacitance, impedance or bandwidth can interfere with the normal signal even if the device provides adequate surge protection.

Common Applications

• Industrial instrumentation and sensor circuits
• Data and communication lines
• Telephone and telecommunications circuits
• Network-connected equipment
• Remote control and monitoring circuits
• Low-voltage process and automation signals

Important Selection Factors

• Signal type: Identify the communication, instrumentation or control protocol being protected.
• Normal operating voltage: Select protection that does not clamp during normal circuit operation.
• Number of conductors: Confirm how many signal wires require protection.
• Connector or terminal type: Match the physical interface used by the existing circuit.
• Signal frequency or data rate: Confirm that the protector supports the required bandwidth.
• Surge rating: Review the manufacturer’s transient-current and voltage-protection specifications.
• Grounding: Provide the grounding or bonding arrangement required by the protection device.
• Installation location: Position protection according to equipment exposure and manufacturer recommendations.

Power-Line Protection Is Not Enough

Equipment connected to both power and communication wiring can remain exposed to transient energy even when its AC supply has surge protection. Coordinated protection of incoming power and external signal connections can provide a more complete approach for sensitive electronic systems.

Replacement Checklist

• Manufacturer and existing surge-protector part number
• Signal or communication type
• Normal circuit voltage
• Number of conductors
• Connector or terminal arrangement
• Signal frequency or data rate
• Grounding arrangement
• Photographs of the existing device and connections