What does the R mean on a fuse?
What does the R mean on a fuse?
MVR fuses are current and energy limiting fuses intended for the backup protection of medium voltage motor control. They are non- venting.
What is the difference between Class R and Class J fuses?
Class R fuses are available with DC ratings. They have an interrupting rating of 200kA rms symmetrical and are separated into two separate classes, RK1 and RK5. Current ratings of UL Class J fuses range from 0A to 600A, and the voltage rating is 600VAC. Class J fuses are available with DC ratings.
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 class fuse mean?
Class K-1 fuses provide the best degree of current limitation. On the other hand, Class K-5 fuses provide a lesser degree of current limitation. The standards requirements for Class K fuses prescribe maximum peak let-through current and maximum I2t let-through energy for each class and all are current-limiting fuses.
What do letters mean on fuses?
The number and the A (may be mA) is the amp rating of the fuse. The L denotes that it is a low breaking capacity or glass fuse (H is High breaking capacity and is usually a ceramic package). Taking the example above a T2AL250V fuse is a 2 Amp, Time Delay glass fuse rated for 250 Volts.
What does SC stand for on a fuse?
• SC-(amp) Description: Basic protection Class G size-rejecting, current limiting fuses. 1/2 to 6A Fast-acting, 7 to 60A time-delay.
What are Class H and K fuses?
Classes H, K, and R are “full-size” fuses, often used in motor applications. You’ll find all three classes with voltage ratings of 250V or 600V, while amp ratings range from one-eighth of an amp up to 600A.
What are Class L fuses used for?
What is a UL Class L, Fuse? A Class L fuse is 600 volt AC current limiting, fuse that is rated to interrupt a minimum of 200,000 amps. Both fast acting, and time delay versions of the Class L fuse is offered.
What does H mean on A fuse?
What is a Class H, Fuse? A UL Class H fuse is a non-current limiting, fuse that is rated to interrupt a minimum of 10,000 amps. The Class H fuse is a one-time fuse that does not have any appreciable degree of time delay. Class H fuses are rated at either 250 volts AC or 600 volts.
What is AP rated fuse?
Standard time delay fuses are for motor loads. For Canadian requirements, a type “P” fuse is used for non-motor loads and type “D” fuses are used for electric heating and cycling loads circuits. Both fuses have low melting-point temperature elements. Type “S” plug fuses are time delay and tamper-resistant.
Are SL and TL fuses interchangeable?
The two are not interchangeable. Two categories of plug fuses are available. The medium duty fuses (TL or SL) have a time delay feature for use on motor circuits. The T or S fuses have more time delay than the medium duty fuses in order to better protect motors and critical residential circuits.
What is a fuse class?
Fuse (automotive) Automotive fuses are a class of fuses used to protect the wiring and electrical equipment for vehicles. They are generally rated for circuits no higher than 32 volts direct current, but some types are rated for 42-volt electrical systems. They are occasionally used in non-automotive electrical products.
What is a FRN are fuse?
The FRN-R-10 is a 10A FUSETRON™ advanced protection energy efficient dual element Time-delay Fuse provides motor overload, ground fault and short-circuit protection. Helps protect motors against burnout from overloads. Helps protect motors against burnout from single-phasing on three-phase systems.
What is a Class T fuse?
Class T Fuse. What is a UL Class T Fuse? A Class T fuse is a fast acting current limiting fuse that is rated to interrupt a minimum of 200,000 amps.
