Blackburn ATC 500 R 250 TN AL Tap Comp Reducer TINPL 500-250

The ATC 500 R 250 TN is a tapered compression reducer that takes a 500 kcmil run conductor down to a 250 kcmil tap, which is what the 500-250 in the part number refers to. It is a one-piece compression splice, not a mechanical bolted lug, so both ends are crimped with a die-type compression tool.

It is an aluminum-bodied reducer that is tin plated, which is the dual-rated construction used for aluminum-to-aluminum and aluminum-to-copper connections. The tin plating is what keeps the aluminum barrel from galvanic attack where it contacts copper. Confirm the AL9CU marking stamped on the barrel matches the combination you are making.

No insulation on this one. The reducer ships as a bare metal barrel, so the finished splice has to be insulated in the field with tape, heat shrink, or a cold-shrink sleeve rated for the circuit voltage. Budget for that material and for the 5-5/8 inch barrel length plus your overlap when you size the sleeve.

It is built to ANSI C119.4, the standard covering connectors for use between aluminum and copper conductors. That is the reference most utility and commercial electrical specs cite for splices and reducers of this type. It is also made in the United States, which matters on Buy American and federally funded work.

The body measures 5-5/8 inches long, and you need clearance beyond that for the crimp tool head on both ends plus the insulating sleeve. In a tight junction box or wireway, lay the barrel out against the available space before you commit, because a compression splice cannot be shortened the way a bolted two-hole lug arrangement can be repositioned.

A compression reducer like this one is crimped permanently and cannot be taken apart, which is why it is specified where vibration, thermal cycling, or submersion would eventually loosen bolted hardware. If you need the joint to come apart later for testing or reconfiguration, use a mechanical set-screw reducer instead. For a splice that gets buried, encased, or left in a manhole, the compression version is the one to install.

Order it as Blackburn ATC 500 R 250 TN. The TN suffix is the tin plated version, and the ATC prefix designates the aluminum tapered compression reducer family.

Sold each, so ordered quantity equals the number of splices you can make. Order one per conductor transition, and remember a three-phase run with a neutral needs four.