Surge Protector for Dry Contact Relays

OVERVIEW

Today’s increased reliance on very sensitive electronics makes surge protection an important topic for most industries. The Insurance Institute for Business & Home Safety study found that $26 billion dollars was lost due to non-lightning power surges. In addition, there are about 25 million lightning strikes in the US each year that cause between $650M to $1B in losses 250Vcording to the Insurance Information Institute, State Farm©.

Dry Contact Relays are a key component of any UL 508A control panel (also known as an Industrial Control Panel or ICP). However, they are usually overlooked due to their limited cost in the overall system yet are integral parts that can lead to costly and disruptive downtime. The Electromechanical Relay is used to provide an electrical connection between two or more points in response to the application of a control signal in control systems applications found in refrigeration, HVAC, compressed air systems, refineries, chemical plants, power plants as well as commercial, industrial, residential and manufacturing process applications. They are the critical components in the process loop and are sensitive to transient over voltages.

This section will identify the UL 1449 Surge Protective Device (SPD) to efficiently protection your digital outputs and increase its reliability.

Protection Point for
Dry Relay Contacts

Based on the built-in withstand of the equipment, Dry Relay Contacts can be protected using the SPD shown below :

Location	Equipment	System	Surge Protector Model #	Link
	Dry Relay Contact	12-24Vdc 12-24Vdc	DS220S-24DC
		24-48Vac 24-48Vdc	DS230S-48DC
		12-127Vac 12-180Vdc	DS240S-120
		130-250Vac 180-300Vdc	DS240S-230
		277-380Vac 300-510Vdc	DS240S-400

10108 USA Today Way Miramar, FL 33025 USA