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HUBBELL Mechanical Interlock: 120/240V AC, Single Phase, 20 A, 3 Pole - Watertight Interlocks
HUBBELLWatertight Interlocks

HUBBELL Mechanical Interlock: 120/240V AC, Single Phase, 20 A, 3 Pole

The HUBBELL Mechanical Interlock (MPN HBL420MI12W) is a watertight interlock rated for 120/240V AC, single phase, 20 A, with 3 poles and 4 wires. This unit does not support reverse service.

SKU 3G-OTH-14065

Brand
HUBBELL
Item
Mechanical Interlock: 120/240V AC, Single Phase, 20 A, 3 Pole
Category
Watertight Interlocks
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Technical Specifications

HUBBELL
Manufacturer Part Number
HBL420MI12W
Voltage Rating
120/240V AC
Reverse Service
No
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HUBBELL Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The HUBBELL Mechanical Interlock (MPN HBL420MI12W) is a watertight interlock rated for 120/240V AC, single phase, 20 A, with 3 poles and 4 wires. This unit does not support reverse service.

Frequently Asked Questions

What is the HUBBELL Mechanical Interlock HBL420MI12W used for?

The HUBBELL Mechanical Interlock HBL420MI12W is a watertight interlock used to safely connect and disconnect portable generators or temporary power sources in industrial and commercial settings. It prevents simultaneous connection of utility and generator power, ensuring operator safety during maintenance or backup power operations.

What are the specifications of the HUBBELL Mechanical Interlock HBL420MI12W?

The HUBBELL Mechanical Interlock HBL420MI12W is rated for 120/240V AC, single phase, 20 A, with 3 poles and 4 wires. It is a watertight interlock with no reverse service capability. The manufacturer part number is HBL420MI12W, and it is designed for reliable electrical isolation in demanding environments.

Where to buy the HUBBELL Mechanical Interlock HBL420MI12W worldwide?

You can source the HUBBELL Mechanical Interlock HBL420MI12W through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we supply genuine HUBBELL components for your project needs.

How to install the HUBBELL Mechanical Interlock HBL420MI12W?

Install the HUBBELL Mechanical Interlock HBL420MI12W by mounting it in a suitable watertight enclosure, connecting line and load conductors per the wiring diagram, and ensuring the interlock mechanism prevents both sources from being engaged simultaneously. Always follow local electrical codes and consult a qualified electrician for safe installation.

Used in

Common applications for HUBBELL
Commercial lighting control — HUBBELL toggle switches (e.g., HBL1203STW) for 3-way switching in office corridors
Industrial maintenance — HUBBELL overhead cables (e.g., OC5MB-03) for tool balancers in assembly lines
Institutional wiring — HUBBELL rocker switches (e.g., DS115ST) for single-pole control in school classrooms
Facility upgrades — HUBBELL decorator wall plates (e.g., P262GY) for standard 2-gang outlet covers in commercial buildings
Electrical repair — HUBBELL panel terminal screws (e.g., HBLTSR) for replacing worn terminals in Series 16 devices
Modern interface — HUBBELL touch switches (e.g., WSS1277SS) for maintained 3-way control in hospitality settings

HUBBELL Products

3G Electric supplies HUBBELL watertight interlocks. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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