ESDR4 / ESDR4T

The ESDR 4/4T offers a three-phase current differential protection for generators, motors, and transformers that are interconnected.

ESDR4: 

Current differential protection for generators and motors

ESDR4T: 

Current differential protection for generators, motors, and transformers in unit connection.

View ESDR4 block/generator protection application

Common Product Features: 

• True RMS 6× current measurement
• 3-phase system on both sides of the protected zone
• secondary current transformer output available as ../1 A or ../5 A
• Configurable delays
• 4 alarm relays
• 3 discrete inputs (for blocking, acknowledgement, and configuration
• Configurable tripping characteristic
• Configurable independent thresholds for
• Differential current protection (Id)
• Stabilizing current protection (Is)

Additional ESDR4T Features: 

• Configurable transformer ratio
• Configurable vector group
• Transformer inrush detection/suppression
• Individually configurable current transformer ratios for high and low voltage sides of the transformer being protected

Certifications / registrations: UL/cUL, CE, GL (ESDR4T only)

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Note: Information contained herein is intended for and appropriate to the purposes of this publication. Woodward reserves the right to update or otherwise revise any portion of this publication at any time. Technical data and detailed information is available in Woodward product specs. Specific reliance should be given only to information contained in purchase order(s), other contractual document(s), or information otherwise expressly represented in writing by Woodward as correct and accurate for the specific facts, circumstances and applications.