Surge suppressors, dataline and DC signal, are used to protect equipment from transient overvoltages present on data or DC signal lines. The suppressor may operate by absorbing the surge (the shunt type suppressor) or by blocking the surge from flowing (the series type suppressor) or by a combination of the two. The shunt type suppressor has a characteristic clamping voltage that is normally chosen to be around the maximum safe operating voltage of the circuit. To prevent equipment damage from both internal and external surges, point-of-use surge protection devices (SPDs) can be used.

Surge suppressors, dataline and DC signal can be used for many different applications.  These include data acquisition, network applications, telecom applications, and audio and video applications.  Surge suppressors can be used to protect data acquisition devices such as RTDs, TCs, 4-20ma process control loop systems.  Network application surge suppressors are used in networks to protect data and transmission lines such as ISDN, LAN Applications (i.e. Ethernet, Token Ring, ARCNET etc.)  Telecom surge suppressors are utilized to protect telecommunication lines and devices such as faxes, modems, telephones, etc.  Audio and video surge suppressors are used to protect AV equipment such as cable TVs, rooftop antennas or down line TVs.  Connector choices for surge suppressors, dataline and DC signal include RJ11 / RJ13 / RJ14 phone jacks, RJ41 / RJ45 / RJ48 data jacks, screw down terminals, DB connectors (DB-9, DB-25, etc.), and coaxial cable connectors.

Surge suppressors, dataline and DC signal, are used to protect equipment from transient overvoltages present on data or DC signal lines. The suppressor may operate by absorbing the surge (the shunt type suppressor) or by blocking the surge from flowing (the series type suppressor) or by a combination of the two. The shunt type suppressor has a characteristic clamping voltage that is normally chosen to be around the maximum safe operating voltage of the circuit. To prevent equipment damage from both internal and external surges, point-of-use surge protection devices (SPDs) can be used.

Surge suppressors, dataline and DC signal can be used for many different applications.  These include data acquisition, network applications, telecom applications, and audio and video applications.  Surge suppressors can be used to protect data acquisition devices such as RTDs, TCs, 4-20ma process control loop systems.  Network application surge suppressors are used in networks to protect data and transmission lines such as ISDN, LAN Applications (i.e. Ethernet, Token Ring, ARCNET etc.)  Telecom surge suppressors are utilized to protect telecommunication lines and devices such as faxes, modems, telephones, etc.  Audio and video surge suppressors are used to protect AV equipment such as cable TVs, rooftop antennas or down line TVs.  Connector choices for surge suppressors, dataline and DC signal include RJ11 / RJ13 / RJ14 phone jacks, RJ41 / RJ45 / RJ48 data jacks, screw down terminals, DB connectors (DB-9, DB-25, etc.), and coaxial cable connectors.

Important performance specifications to consider when searching for surge suppressors, dataline and DC include number of protected lines, maximum surge current, clamping voltage, rated DC energy absorption, maximum DC power distribution, and UL listings.  The number of protected lines includes the number of 'pairs' or lines protected from surges.  Maximum surge current is the maximum current allowed for a single impulse waveform with continuous voltage applied. This level is used to indicate the protection capacity of a particular surge suppressor design, and when specifying a suppressor for a given application. For example, in a high exposure application with very large transients present from lightning, a higher-level surge current capacity would be required.  The clamping voltage is the DC Clamping level (Typically <300 for phone, <35 for TV), the actual clamping voltage of an SPD, the amount of voltage necessary to actuate the device, and equals the "let through" voltage.  The rated DC energy absorption is the measurement of a Surge Protective Device's ability to absorb heat energy created by transient surges. Note that the Joule rating is not a part of IEEE or UL Standards.  UL ratings include UL 497A rating, UL 1459 rating, and UL 452 rating.

Mounting choices for surge suppressors, dataline and DC include wall, panel or backboard mount, DIN rail, rack mount, hard-wired or device mount, in-line or integrally attached, plug-in module, and PCB mount.  Common features of surge suppressors, dataline and DC include self-diagnostics, complete pin protection, on / off switch, status or diagnostic LEDs, resettable circuit breakers, thermal fusing, audible alarms, grounding wires, surge counters, and remote alarm contacts.  Technology choices for surge suppressors, dataline and DC include MOV (Metal Oxide Varistor), silicon avalanche diode, silicone thyristor diode, gas tube, and hybrid.  An important environmental parameter to consider when specifying surge suppressors is the operating temperature.