What are Class H and K fuses?
What are Class H and K fuses?
Class H has a small interrupt capacity of 10,000A. Some are current-limiting, but only up to their interrupt capacity. You can’t tell if they are current-limiting, because none of them are marked. Class K fuses come in two interrupt ratings: 50,000A and 100,000A.
What is the difference between RK1 and RK5 fuses?
What is the difference between UL Class RK1 and RK5 fuses? Class RK1 and RK5 fuses are the same physical size but Class RK1 fuses are more current-limiting than Class RK5 fuses. RK1 fuses can provide better protection because they allow less damaging energy to pass through them while opening (blowing).
What are the different classes of fuses?
UL Fuse Classification Chart
| UL CLASS | FUSE OVERLOAD CHARACTERISTICS | INTERRUPTING RATING, AMPERES |
|---|---|---|
| CD | TIME-DELAY | 200,000 |
| G | TIME-DELAY | 100,000 |
| K5 | FAST-ACTING | 50,000 |
| H | RENEWABLE FUSES FAST-ACTING | 10,000 |
What does H on A fuse mean?
H. High Breaking Capacity. L. Low Breaking Capacity. Note: Many small cartridge fuses will have additional markings stamped on the end caps.
Are Class K fuses current limiting?
Class K fuses are not permitted to be labeled Current Limiting because there is no rejec- tion feature as required by NEC® Article 240-60(B). INTERRUPTING RATING: 200,000 amps rms symmetrical Not interchangeable with any other UL fuse class.
Are Class H fuses current limiting?
Since Class H fuses are not current- limiting and are recognized by regulatory agencies as having only a 10,000A interrupting rating, serious damage could result if a Class R fuse were replaced by a Class H fuse.
What are RK5 fuses used for?
Edison dual element time-delay class RK5 fuses are recommended for AC power distribution mains, feeders and branch circuits for motors and transformers, or lighting and heating.
What is A RK5 fuse?
What is a Class RK5 Fuse,? A UL Class RK5 fuse is a current limiting, time delay fuse, that is rated to interrupt a minimum of 200,000 amps. The UL Class RK5 fuse is less expensive but less current limiting than the Class RK1 fuse,. It has a dual element, construction.
What are Class J fuses used for?
Class J fuses are commonly used in branch circuits, motor circuits, mains, feeders, control panels, electronic motor controllers, drives, soft-starters, circuit breaker back-up, transformers, load centers, lighting, heating and general loads to name a few.
What is a Class H breaker?
H-interrupting class breakers offer short-circuit current ratings up to 65 kA at AC 480 V. The short-circuit current rating is the maximum available current of the circuit where the switch is used, when protected by an appropriate overcurrent protective device.
