ABB 345B995G31 Oil-Immersed Expulsion Protective Mesh Link for 34.5 kV Class Distribution Transformer

Product Specifications

Product Name: ABB Liquid-Submersed Expulsion Protective Link Fuse

OEM Catalog Number: 345B995G31

Maximum Rated System Voltage: 34.5 kV Class (Line-to-line grounded Y configuration)

Fusing Curve Designation: Calibrated to standard factory time-current curve parameters

Installation Mounting Profile: Sub-surface under-oil flexible long-lead block mounting

Core Materials: High-conductivity flexible copper wire leads and industrial porous mesh sleeve

Available Voltage Series & Calibration Matrix

The ABB oil-immersed protective link series is engineered across three distinct insulation voltage classes to satisfy global utility grid demands:

• 15 kV Maximum Matrix: Utilizing original 592B581 series specifications for lower insulation classes.
• 23 kV Maximum Matrix: Mid-range sub-surface variants utilizing original 779C667 engineering drawings.
• 34.5 kV Heavy-Duty Class (This Model): Part Number 345B995G31 — features an extended creepage structural profile built specifically for high-stress 34.5 kV utility distribution networks.

Material & Structural Characteristics

• Porous Woven Mesh Sleeve: Heavy-duty, oil-compatible structural wrapper designed to facilitate uniform dielectric oil circulation while safely venting internal carbon gases during element clearing.
• High-Purity Copper Long Leads: Built from 100% electrical-grade flexible copper to ensure low contact resistance and eliminate thermal drift during long-term continuous immersion in hot dielectric fluid.
• Engineered Fusible Element Core: Precision-drawn element wire exhibiting exceptionally tight metallurgical tolerances to preserve absolute consistency across specified time-current melting curves.
• Vibration-Proof Crimp Joints: Mechanically reinforced terminal joints engineered to withstand constant transformer core-and-coil operational vibrations without cracking or loosening.

Product Functions

1. Low-Magnitude Fault Isolation: Precision-calibrated to clear low-magnitude currents, secondary faults, external overloads, and high-impedance internal faults within the transformer that fall below the minimum interrupting threshold of back-up current-limiting components.

2. Two-Part Full-Range Coordination: Operates in perfect synchronization when connected in series with a partial-range current-limiting fuse. It isolates minor overloads locally while transferring severe high-current short circuits safely over to the back-up current-limiting element.

3. Grid & Apparatus Protection: Minimizes the duration of electrical arcing during insulation breakdown, preventing downstream faults from escalating and isolating the flawed apparatus to limit the number of affected utility customers.

Key Features

1. High-Voltage Utility Certification: Fully engineered and verified to comply with rigorous ANSI/IEEE overcurrent protection standards, ensuring clean clearing inside tight pad-mounted and pole-mounted transformer tanks.

2. Flexible Long Lead Architecture: Fabricated with extended high-conductivity copper leads to offer field technicians seamless routing and quick, secure crimping inside complex sub-surface transformer connection blocks.

3. Non-Aging Dielectric Compatibility: Formulated from premium materials that prevent oil contamination and chemical degradation inside hot transformer mineral oil or alternative bio-based Envirotemp FR3 fluids.

4. Rugged Product Identification: Permanently stamped with the exact ABB factory part number 345B995G31 and clear voltage identifiers to allow smooth inventory tracking and error-free warehouse deployment.

5. 100% Comprehensive Factory Testing: Every single production unit undergoes rigorous physical inspection, detailed micro-ohm electrical resistance testing, and precise metallurgical batch verification before shipment.

Technical Parameter Specifications

• Nominal Current Curve: Factory-calibrated for specific low-current clearing limits
• Max. System Voltage: 34.5 kV Line-to-Line Grounded Y Distribution Network
• Interruption Medium: Liquid-Submersed Expulsion Protective Link
• Application Layout: Pad-mounted Distribution Transformers, Box-type Substations, Pole-Top Overhead Transformers, Medium-Voltage Under-Oil Disconnect Assemblies.
• Compliance Matrix: Manufactured in complete alignment with IEEE distribution component specifications.