ABB Installation Products 274FLR3-B0240 Molded Current Limiting Fuse Housing, Nominal Fuse Voltage Rating 17.2kV, Fuse Test Port…

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How to Install the 274FLR Loadbreak Fused Elbow Connector

This guide provides step-by-step instructions for the safe installation and initial wiring of the 274FLR (or 168FLR) Loadbreak Fused Elbow Connector, including cable preparation, component assembly, and connection to a bushing plug.

Estimated time: 1h 30m

1. Perform Pre-Installation Checks and Safety Procedures

   Ensure all apparatus are de-energized during installation. Verify all package contents are complete and undamaged, including the Cable Half Housing, Elbow Half Housing, Fuse, Compression Lug, Probe, Probe Connector, Hose Clamp, Probe Wrench, Allen Wrench, and Lubricant. Inspect all components for proper fit with the cable and/or mating products. Thread the probe into the compression lug to check threads; if resistance is encountered prior to full assembly, check for damage and replace the component. Read the entire installation instructions before starting. Have all required tools at hand and maintain cleanliness throughout the procedure. This product must be installed only by competent personnel trained in good safety practices involving high voltage electrical equipment.

2. Prepare the Cable for Termination

   Using the bushing centerline as a reference, cut excess cable off 20 inches minimum beyond the bushing. If using an optional 200ECS Cold Shrink Cable Seal, slide it onto the cable. Remove the jacket from the excess cable length and an additional distance of 'A' (15-3/4 inches for 274FLR-3) + 7-3/8 inches from the bushing centerline. If a Cable Seal kit is used, follow its instructions; otherwise, unwrap and fold the concentric neutral wires back over the jacket and bind them. Using the bushing centerline as a reference, squarely cut off the cable a distance of 'A' (15-3/4 inches for 274FLR-3), leaving 7-3/8 inches minimum of cable to terminate. Cut 1-1/8 inches from the cable end, squarely and without nicking the conductor. Wire brush bare aluminum conductors and immediately install the compression lug, rotating to spread inhibitor. Crimp the unthreaded end of the compression lug to the conductor (refer to the crimp chart for tool information), starting at the crimp line mark and rotating 180 degrees for each successive crimp. Carefully wipe excess inhibitor from the outside of the lug and cable. Remove the insulation shield 5-1/2 inches from the end of the lug. Bevel the insulation end 1/8 inch maximum. Thoroughly clean the insulation to remove all traces of conductive residue.

3. Lubricate and Insert Cable into Cable Half Housing

   Apply the supplied lubricant to the outside of the connector, cable insulation, conductive shield, and the cable entrance end of the Fused Elbow cable half. DO NOT SUBSTITUTE lubricant. Insert the connector and cable into the cable half of the Fused Elbow until the top end of the connector protrudes beyond surface 'A'. This protrusion allows the fuse to be tightened before bottoming on the rubber.

4. Install and Hand-Tighten the Fuse

   Insert the threaded terminal end of the fuse into the cable half of the Fused Elbow and hand-tighten it into the cable connector. CAUTION: The fuse stud will fracture if over-torqued. Pull the housing up against the bottom of the tightened fuse.

5. Assemble and Lock the Probe Connector

   Assemble the probe connector to the fuse terminal. Rotate the probe connector so that its flats are perpendicular to the bushing with which it will mate. Lock the probe connector in position by tightening the setscrews using the special torque-limiting allen wrench supplied in the fuse kit. Rotate the cable half of the Fused Elbow so that the test point is perpendicular to the flats on the probe connector.

6. Assemble Elbow Halves and Insert Probe

   Apply lubricant to the elbow half of the fused elbow and assemble it to the cable half of the fused elbow. The cuff of the cable half will overlap the elbow half by 3/4 inch. Ensure the probe connector faces the opening of the fused elbow half and that the two test points are in line with each other. Insert the probe into the probe connector; it may be necessary to push on the cable to align the probe with the fuse. Start the threads by hand, taking care not to cross-thread the probe. To tighten, use the special torque-limiting allen wrench supplied: insert the short end of the wrench into the hole in the probe and tighten until the wrench bends and remains bent. Position the hose clamp as shown in the diagram and tighten it, but DO NOT OVERTIGHTEN.

7. Connect Concentric Neutral Wires to Ground

   Using a separate copper wire (No. 14 AWG / 2.5mm) or equivalent, insert one end through each grounding eye on the elbow housing and cable housings. Twist tightly, taking care not to damage the eyes. If a 200ECS jacket seal was used, finish installing it. Twist all neutral wires, exercising care not to damage grounding eyes, and connect them to ground using an appropriate connector. Provide adequate slack in the wires for elbow operation.

8. Connect the Fused Elbow to the Bushing Plug

   Lubricate the receptacle portion of the elbow connector and the mating bushing with the supplied lubricant. IMPORTANT: Lubricate only if the transformer and elbow are known to be de-energized. Securely fasten a hotstick to the loadbreak connector pulling eye. Place the elbow connector receptacle area over the bushing plug, inserting the elbow male contact (arc follower portion) into the bushing until the first slight resistance is felt. Immediately push the elbow home with a fast, firm, straight motion, applying sufficient force to engage the internal lock on the elbow connector and bushing interface. DO NOT OPERATE BY HAND.

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