Protection Relays & Systems

This Product Selection Guide contains information to help select products in the Protection Relays & Systems category on DigiKey.com

Protection relays detect abnormal operating conditions in an industrial system and may trigger an alert or isolate the offending device from the system. Common detection functions include; Arc-flash, temperature monitoring, ground fault, over-current, over-voltage, reverse power flow, over-frequency, under-frequency and phase loss, sequence or imbalance.


SelectionCharacteristics

Function: Indicates the style and configuration of the device.

Voltage - Supply: Typically represented by a range, this indicates the low and high voltage limits which one can expect standard operation. Voltages outside this range may damage the device and other system components.

Trip Range: Indicates the range over which a device’s monitoring threshold can be adjusted.

Delay Time: Describes a fixed or adjustable period of time after a monitored circuit exceeds some defined threshold that a device will wait before actuating its output.

Mounting Type: Indicates how the device is attached.

Termination Style: Selection of termination style used to connect the device to a system, such as screw terminals or wire leads.

Features: These are different capabilities or properties of the device such as an automatic reset or test button.

Operating Temperature: Recommended operating temperature, typically given in a range or as a maximum. Exceeding these temperatures may affect performance or damage the device and other system components.

ProductExamples

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MFR PART # 3RN20101CW30
DIGI-KEY PART # 3473-3RN20101CW30-ND
MANUFACTURER Siemens
DESCRIPTION THERMISTOR MOT. PROT. 1NO 1NC BI
DATASHEET Click Here

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MFR PART # 777-P2
DIGI-KEY PART # F10492-ND
MANUFACTURER Littelfuse Inc.
DESCRIPTION 3-PHASE OLR/200-480V/2-800FLA+
DATASHEET Click Here

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MFR PART # GFD-100
DIGI-KEY PART # 314-GFD-100-ND
MANUFACTURER Mueller Electric Co
DESCRIPTION THREE PHASE GROUND FAULT DISPLAY
DATASHEET Click Here

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MFR PART # DEA71DM24A003
DIGI-KEY PART # 1864-2893-ND
MANUFACTURER Carlo Gavazzi Inc.
DESCRIPTION EARTH LEAKAGE MONITORING RELAY
DATASHEET Click Here

If you have any general questions on the specifications for selecting Protection Relays & Systems, please reply using the button below. If you have questions on specific Protection Relays & Systems please post those questions in the Industrial Automation and Control category.