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MASTER LOCK Circuit Breaker Lockout: Clamp-On, For 120/240V AC Volt - Clamp-On Circuit Breaker Lockouts
MASTER LOCKClamp-On Circuit Breaker Lockouts

MASTER LOCK Circuit Breaker Lockout: Clamp-On, For 120/240V AC Volt

The MASTER LOCK S3821 is a clamp-on circuit breaker lockout designed for 120/240V AC miniature circuit breakers. It does not include a cable tie slot. 3G Electric interprets your safety requirements and sources this…

SKU 3G-OTH-556436

Brand
MASTER LOCK
Item
Circuit Breaker Lockout: Clamp-On, For 120/240V AC Volt
Category
Clamp-On Circuit Breaker Lockouts
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Technical Specifications

MASTER LOCK
Manufacturer Part Number
S3821
Type
For 120/240V AC Volt, S3821
For Voltage
120/240V AC
For Use With
Miniature Circuit Breakers
Includes Cable Tie Slot Final
No
View Full Spec Sheet

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MASTER LOCK Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The MASTER LOCK S3821 is a clamp-on circuit breaker lockout designed for 120/240V AC miniature circuit breakers. It does not include a cable tie slot. 3G Electric interprets your safety requirements and sources this genuine lockout as part of our broader industrial supply capability across 14 departments, with specialist depth in electrical controls.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is the MASTER LOCK S3821 circuit breaker lockout used for?

The MASTER LOCK S3821 is a clamp-on lockout device used to secure miniature circuit breakers during maintenance. It prevents accidental re-energization by locking the breaker in the off position, ensuring worker safety on 120/240V AC systems. 3G Electric sources this genuine lockout as part of our industrial safety supply.

What are the specifications of the MASTER LOCK S3821?

The MASTER LOCK S3821 is rated for 120/240V AC and is designed for use with miniature circuit breakers. It features a clamp-on design and does not include a cable tie slot. The manufacturer part number is S3821. 3G Electric supplies this lockout across 14 industrial departments, with specialist depth in electrical controls.

Where to buy the MASTER LOCK S3821 lockout worldwide?

3G Electric supplies the MASTER LOCK S3821 clamp-on circuit breaker lockout to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. As a global industrial solutions provider, we interpret your safety requirements and source genuine MASTER LOCK products for reliable lockout/tagout compliance.

How to install the MASTER LOCK S3821 on a circuit breaker?

To install the MASTER LOCK S3821, first ensure the circuit breaker is in the off position. Clamp the lockout device over the breaker toggle until it snaps into place. Then insert a padlock through the lockout holes to secure it. Always follow your facility's lockout/tagout procedures. 3G Electric can advise on proper selection for your breaker type.

Used in

Common applications for MASTER LOCK
Locker security in industrial facilities — Master Lock built-in deadbolt lock (MPN 1710) for employee lockers
Equipment access control on job sites — Master Lock Bluetooth padlock (MPN 4400ECWWG) for tool cribs and gates
Key management for fleet vehicles — Master Lock lockbox (MPN 5440ECWWG) securing vehicle keys at depots
Padlock for outdoor storage units — Master Lock long shackle combination padlock (MPN 175LH) for hasps on sheds
Keyless entry for maintenance panels — Master Lock scrolling combination padlock (MPN 975DCOM) on electrical enclosures
High-security locking for warehouse cages — Master Lock stainless steel combination padlock (MPN 1500LF) for corrosion resistance

MASTER LOCK Products

3G Electric supplies MASTER LOCK clamp-on circuit breaker lockouts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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