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General Information
Allen-Bradley offers two lines of Miniature Circuit Breakers with UL 489 (CSA 22.2 No. 5) certification, four different lines of Supplementary Protectors (Miniature Circuit Breakers), and a line of fuse holders for branch circuit fuses and supplementary fuses.Bulletin 1492-FB Fuse Holders
1492- Fuse Holders provide a DIN Rail-mounted package for use in Class CC, Class J, and Midget fuse applications such as protection of transformers and motors.
Features include:
- EN/IEC 60529 finger protection — dead front construction
- Compact size requiring less panel space than open-style fuse holders
- Optional blown fuse indicator
- Branch circuit protection with Class CC and J fuses
- UL Listed, CSA Certified
- DIN Rail (35 mm), mounted
Bulletin 1492 Circuit Breakers
Allen-Bradley Thermal Magnetic Miniature Circuit Breakers are ideal for protecting control circuitry and load components from damage due to overcurrents and short circuits.
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Potential applications include protection of:
- Solenoids
- Relay/contactor coils
- Transformers
- PLCs
- Computers
- Medical Equipment
- Power Supplies
- PLC I/O Points
UL1077, CSA C22.2 No. 235 — In North America, miniature circuit breakers are recognized as supplementary protectors and are intended for use as overcurrent protection within an appliance or other electrical equipment where branch circuit protection is already provided or not required. Internationally, these products are rated to IEC standards as miniature circuit breakers or circuit breakers for equipment.
UL508, CSA 22.2 No.14 — In North America, some miniature circuit breakers, meeting specific requirements, may be used as Manual Motor Controllers for direct control of motors connected across-the-line equipment where branch circuit protection is already provided or not required. Internationally, these products are rated to IEC standards as miniature circuit breakers and applied for motor controller applications within those standards.
UL489, CSA 22.2 No. 5.1 — In North America, some miniature circuit breakers, meeting specific requirements, may be used as Branch Circuit Protection devices for the protection of electric wiring as well as load protection.
| Type | 1492-GH | 1492-GS | 1492-SP | 1492-MC | 1489 | |
| Certifications | UL | 1077 | 1077 | 1077 | 489 | 489 |
| CSA | 22.2 No. 235 | 22.2 No. 235 | 22.2 No. 235 | 22.2 No. 5 | 22.2 No. 5 | |
| EN/IEC | IEC 60934 | IEC 60934 | IEC 60898 IEC 60947-2 |
— | IEC 60947-2 | |
| CE Marked | Yes | Yes | Yes | No | Yes | |
| No. of Poles | 1 | 1, 2, 3 | 1, 2, 3 – 1+N, 3+N | 1, 2, 3 | 1, 2, 3 | |
| Volts AC | 250 V | 480Y/277 V | 480Y/277 V | 120/240V AC 240V AC |
480Y/277 V | |
| Volts DC | 65 V | 65 V | 1p 48V 2p (series) 125V |
— | up to 500V DC | |
| Current Range | 0.2…15A | 0.2…25A | 0.5…63A | 15…100 A | 0.5…40 A | |
| Trip Characteristics (In) |
G 6…12 | G 6…10 | B 3…5 C 5…10 D 10…20 |
UL 489 Standard (CSA 22.2 No. 5.1) | B 3…5 C, 5…10 D 10…20 |
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| Energy Limiting | No | No | Yes | No | Yes | |
| No. of Pole/foot | 24 | 24 | 17 | Varies | 17 | |
| Mounting Method | DIN Rail & A-B Rail | DIN Rail & A-B Rail | DIN Rail | DIN Rail | DIN Rail | |
| IEC 529 and 60947 Finger Protection | Yes | Yes | Yes | Varies | Yes | |
| Optional | Auxiliary Contacts | No | Yes | Yes | No | Yes |
| Shunt Trip | No | No | Yes | No | Yes | |
| Undervoltage Trip | No | No | Yes | No | Yes | |
Technical Information: The Benefits of Limiting Let-Through Energy
Energy Limiting Circuit Breakers Versus Conventional Breakers
The Bulletin 1492-SP line features the unique ability to achieve short circuit interruptions far more effectively than conventional circuit breakers. In conventional circuit breakers, the short circuit interruption time required is approximately one or two half cycles of an AC sine wave. When the contacts are open, the resulting arc continues to burn until the current level passes through zero. The arc may re-ignite because of the insufficient width of the contact gap. The current that flows until the arc is extinguished produces a heating effect proportional to the I2t value (let-through-energy) of the fault current.
These devices are designed to substantially reduce the amount of let-through-current and the resulting let-through-energy that can damage protected components. They have the ability to interrupt short circuit current within the first half cycle of the fault. Limiting let-through-energy will protect against the harmful effects of over-current and is focused primarily on avoiding the following:
- Excessive heat
- Mechanical damage
Both of these factors are proportional to the square of the current. Thermal energy is proportional to the square of the RMS value and magnetic forces are proportional to the square of the peak value. The most effective way to provide protection is to subtantially limit let-through-energy.This provides the following advantages:
- Far less damage at the location of the short circuit.
- Fast electric separation of a faulty unit from the system, especially power supplies connected in parallel that are switched off when the voltage of the power bus drops below a certain level.
- Far less wear on the miniature circuit breaker itself. This means more safe interruptions.
- Better protection of all components in the short circuit path.
- Far wider range of selective action when used with an upstream protective device. (No nuisance shut downs from feeder line interruptions causing a blackout in all connected branches.)
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