NSi Industries Polaris Insulat...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$335.72
NSi Industries Polaris Insulated In-Line Splice, Plastisol

NSi Industries Polaris Insulated In-Line Splice, Plastisol

(No reviews yet) Write a Review

Model: ISRH-750

In Stock (leaves warehouse same day if ordered before 3pm ET)

$335.72
Adding to cart… The item has been added
Free Shipping on orders over $199
We price match and offer bulk discounts! Click Add to Quote. It's quick and easy.
✨
Earn points with this purchase! You can redeem points for giftcards, iPads, XBox's and more. View Rewards
Free Keying on all locks
You may also like

NSi Industries Polaris Insulated In-Line Splice, Plastisol

The NSi Industries Polaris Insulated In-Line Splice is a 750-250 MCM in-line splicer/reducer built for joining and reducing large stranded conductors in commercial and industrial wire terminations. Constructed with a durable Plastisol insulating cover in black, this splice is rated 600V and 90°C, and is cULus listed for Class B & C wire, giving installers a code-compliant option for demanding conductor-splicing applications.

Key Features

  • Wire Size: Accommodates 750-250 MCM conductors for splicing and reducing large-gauge wire runs.
  • Durable Construction: Plastisol material and finish in black provide reliable insulation over the splice connection.
  • In-Line Splicer/Reducer Type: Designed to join two conductors for splicing or reducing applications in a single in-line connector.
  • Voltage Rating: Rated 600V for use in standard power distribution wire terminations.
  • Temperature Rating: Rated for 90°C environmental conditions, suited to Class B & C stranded wire.
  • Two-Conductor Design: Configured for 2 conductors per splice for straightforward in-line connections.
  • Finish: Plastisol finish in black for consistent insulation coverage.

Certifications & Compliance

  • cULus Listed
  • Rated for 90°C Environmental Conditions
  • 600V Voltage Rating

Technical Specifications

  • Number Of Conductors: 2
  • Brand Name: NSi

Typical Applications

  • Wire Termination for Commercial and Industrial Electrical Installations
  • Splicing and Reducing Large-Gauge Stranded Conductors
  • Class B & C Wire Connections
  • Panelboard and Distribution Wiring
  • Renovation and New Construction Wire Runs

Why NSi Industries?

NSi Industries backs the Polaris In-Line Splice with durable Plastisol insulation, a 600V/90°C rating, and cULus listing, delivering a reliable, code-compliant solution for professional electrical wire terminations. This construction and certification profile makes it a dependable choice for splicing and reducing 750-250 MCM conductors in demanding commercial and industrial environments.

Manufacturer Resources

Spec Sheet

Product Specs

Environmental Conditions:
90 C
Product Material:
Plastisol
Standards:
cULus
Wire Size:
750-250 MCM
Product Finish:
Plastisol
Product Color:
Black
Number Of Conductors:
2
Product Type:
Mechanical Splice Connector
Temperature Rating:
90° C
Wire Type:
Class B & C
Brand Name:
NSi
Voltage Rating:
600V
Application:
Wire Termination
Listing:
cULus
Department:
Electrical
Product Group:
Wire Connectors & Terminals
Product Subgroup:
Splice Kits

NSi ISRH-750 – Frequently Asked Questions

1) What wire sizes does the NSi Polaris ISRH-750 in-line splice accept?
The Polaris ISRH-750 takes conductors from 750 MCM down to 250 MCM, and it takes two of them, one per side. Because the range spans four sizes, you can run it straight (750 to 750) or use it as a reducer, for example 750 MCM to 350 MCM, in the same connector. Anything smaller than 250 MCM is outside the range and needs a smaller-port Polaris body.
2) Can I use this splice to reduce from one conductor size to another, or does it only join equal sizes?
It is built as an in-line splicer/reducer, so dissimilar sizes are the point. Each of the two ports independently accepts anything in the 750 to 250 MCM range, so a 500 MCM feeder can be spliced to a 300 MCM run in one body without a separate reducing lug or adapter.
3) Is the Polaris ISRH-750 rated for 600V feeder work, and is it a listed connector?
Rated 600V, which covers standard 208/240/480V power distribution and feeder splices. It is cULus listed, so it satisfies an inspector looking for a listed splicing means on the conductors it is rated for.
4) Do I need to tape or heat shrink over this splice after I torque it?
No additional taping is needed for insulation. The body is a Plastisol insulated cover in black that encloses the connection, which is why these get used in panelboards, pull boxes and gutters where there is no room to build up a taped splice.
5) Will this splice work on 90 degree C rated THHN/XHHW conductors?
The connector carries a 90 C rating, so it matches conductors and terminations rated at 90 C. Keep in mind the ampacity of the run is still governed by the lowest-rated component in the circuit, not by the splice.
6) Is a Polaris insulated splice a better choice than a compression sleeve for a large feeder repair?
For a 750 to 250 MCM in-line joint, the mechanical Polaris body is the faster route: no hydraulic crimper, no die selection, and no taping or shrink build-up afterward because the Plastisol cover is the insulation. Compression sleeves still make sense where you need the smallest possible finished diameter or a permanent non-re-enterable joint. The Polaris is set-screw style, so it can be opened again if the run changes.
7) I need to splice three conductors together, can I use the ISRH-750?
No. This body is configured for two conductors, one port per side, for a straight in-line splice or reducer. A three-way or multi-tap connection needs a Polaris body with the corresponding port count, not this one.
8) What is the exact part number to order for the 750 MCM Polaris in-line splice?
Order NSi Industries part ISRH-750. That is the single model on the 750 to 250 MCM insulated in-line splice, so there is no finish or size option to specify beyond the part number itself.
How fast can I get the NSi ISRH-750 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the NSi ISRH-750 come with a warranty?
Absolutely. The NSi ISRH-750 is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the NSi ISRH-750?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the NSi ISRH-750 from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
!