Uncategorized

Rockwell 1491/1494 series isolation switch and fuse base

The technical manual for 1491, 1494F/G/H/U series isolating switches and fuse bases released by Rockwell Automation in March 2026 covers the full range of visible blade flange isolating switches, heavy-duty safety isolating switches, hazardous area isolating switches, control circuit/power fuse bases from 30 to 600A. It specifies model selection, electrical parameters, mechanical dimensions, installation wiring, accessory configuration, and certification standards. The entire series supports Class J/R/H fuses, with visible breakpoints, handle lockable, IP20 protection, 200kA short-circuit withstand capability, and meets UL, CSA, CE, CCC, UKCA, and explosion-proof certifications. It is suitable for industrial distribution and equipment main circuit isolation and protection.

Basic Information

Applicable products: 1491, 1494F/1494G/1494H/1494U

Core application: Industrial distribution isolation switch, fuse protection base

Product series and positioning

Series Type Current Core Features Protection

1494U universal visible blade flange switch 30-600A pole/cable dual operation, saving 30% space 3R/4/12/4X

1494F fixed depth flange installation switch 30-100A fixed depth, simplified installation 1/3R/12

1494G heavy-duty/hazardous area switch 30~600A explosion-proof certification, visual window, metal shell 3R/4/12/4X, 7/9

1494H heavy-duty safety switch 30~200A side mounted handle, can hang 3 locks 1/3R/12

1491 fuse base 0.5~600A control circuit/power circuit, branch protection IP00

Core electrical parameters

rated value

Voltage: AC 600V/DC 250-600V

Current: 30/60/100/200/400/600A

Short circuit withstand: 200kA (equipped with Class J/R fuse)

Mechanical lifespan: 10000 to 20000 cycles

Switching frequency: 3-6 times/minute

Fuse adaptation

Support types: Class J, Class R, Class H

600A specification: J-shaped direct bolt fixation, no clamp needed

Terminal and torque

Wire diameter: 14AWG~500MCM (copper/aluminum)

Torque: 20~305 lb · in (2.3~34.5N · m)

Material: Copper Tin Plating

Structure and safety characteristics

Visual blade structure

The entire system has visible breakpoints that meet NFPA 79 safety requirements.

Handle and locking

Standard OFF position with padlock function

1494H can simultaneously hang 3 padlocks

The ON lock requires on-site modification

operating mechanism

1494U supports dual operation of pull rod/cable

Cable length: 3~6ft (0.9~1.8m)

Protection level

Indoor: Type 1/12

Outdoor/Waterproof: Type 3R/4/4X

Hazardous location: Type 7/9 (1494G)

Attachment system

Auxiliary contact

Specification: 10A, NO/NC, combination type

Model: 1494U-NO, 1494U-NC, 1495-N8, etc

Electrical interlock

Early disconnect design to protect electronic components

Specifications: 2NO, 2NO+2NC

terminal block

Single core/multi-core: copper/aluminum

Model: 1494U-LA/LC series

Fuse clip and cover

Clamp seat: 1401-N41~N55 series

Shield: IP20 anti touch finger protection

Certification and Standards

North America: UL, CSA

International: CE, UKCA, CCC

Explosion proof: Class I/II hazardous areas (1494G)

Standard: UL98, UL508, CSA C22.2 No.4

Key issues

Question 1 (Selection Focus)

What are the core differences between 1494U and 1494G isolation switches, and what scenarios are they applicable to? answer:

1494U: Universal type, supports pole/cable dual operation, small size and space saving, suitable for conventional industrial cabinets, standardized power distribution, without explosion-proof certification.

1494G: Dedicated for heavy-duty and hazardous locations, certified as Class I/II explosion-proof, with visible windows and reinforced metal casing, suitable for chemical, oil and gas, and dust explosion hazardous environments.

Question 2 (Safety Focus)

What safety requirements does the “visible blade” and “handle padlock” of this series of isolation switches meet, and what are the restrictions on their use? answer:

Visual blade: Provides visible breakpoints for physical disconnection, meeting NFPA 79 safety requirements for power-off maintenance.

Handle padlock: equipped with OFF position padlock to prevent accidental closing; The ON position padlock requires on-site modification and is not recommended for use in safety mandatory functions.

Question 3 (Application Focus)

1491 fuse bases are divided into control circuit type and power type. What are the differences between the two in terms of current, voltage, and protected objects? answer:

Control circuit type (1491 control): 0.5~30A, 600V, used for transformer, control circuit, PLC power protection, equipped with Class CC fuses.

Power type (1491 power): 30~600A, 600V AC/250V DC, used for main circuit, motor, and high-power equipment protection, equipped with Class J/R/H fuses.

Leave a Reply

Your email address will not be published. Required fields are marked *