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250Vac/150Vdc 10-60A Classs R Time Delay RK5 Fuse
Can be applied in circuits subject to temporary motor overloads and surge currents to provide both high-performance short-circuit and overload protection
The overload element provides protection against low-level overcurrent of overloads, and will hold an overload which is five times greater than the amprating of the fuse for a minimum of 6~10 seconds
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Description
Standards / Approvals
- Refer To UL 248.1/UL 248.12
- Reach Declaration Available Upon Request
- CE
- RoHS Compliant
Current-Limiting Effects of HCNR Fuses
| SHORT CIRCUIT CURRENT* | APPARENT RMS SYMMETRICAL CURRENT FOR VARIOUS FUSE RATINGS | |
|---|---|---|
| 30A | 60A | |
| 5000 | 1400 | 2100 |
| 10000 | 1550 | 2500 |
| 15000 | 2000 | 3150 |
| 20000 | 2250 | 3400 |
| 25000 | 2400 | 3750 |
| 30000 | 2550 | 4100 |
| 35000 | 2650 | 4300 |
| 40000 | 2800 | 4400 |
| 50000 | 3000 | 5000 |
| 60000 | 3200 | 5250 |
| 80000 | 3400 | 5750 |
| 100000 | 3850 | 6000 |
| 150000 | 4100 | 7000 |
| 200000 | 4300 | 7500 |
Data Sheet Compared to Other Brands
| Series | Mfg | Fuse Type | Operating Speed | Amps | VAC | VDC | Primary Approval | Description |
| HCNR | Hiitio | Class RK5 | Time Delay | 1-60A | 250 | 150 | UL Listed | UL 248-12, Class RK5 |
| FRN-R 1/10-60A | Bussmann | Class RK5 | Time Delay | .100A-60A | 250 | 125 | UL Listed | UL 248-12, Class RK5 |
| FRN-R 70-600A | Bussmann | Class RK5 | Time Delay | 70A-600A | 250 | 125 | UL Listed | UL 248-12, Class RK5 |
| FRS-R 1/10-60A | Bussmann | Class RK5 | Time Delay | .100A-60A | 600 | 300 | UL Listed | UL 248-12, Class RK5 |
| FRS-R 70-600A | Bussmann | Class RK5 | Time Delay | 70A-600A | 600 | 300 | UL Listed | UL 248-12, Class RK5 |
| FLNR | Littelfuse | Class RK5 | Time Delay | .100A-600A | 250 | 125 | UL Listed | UL 248-12, Class RK5 |
| FLNR_ID | Littelfuse | Class RK5 | Time Delay | .100A-600A | 250 | 125 | UL Listed | UL 248-12, Class RK5 |
| FLSR | Littelfuse | Class RK5 | Time Delay | .100A-600A | 600 | 300 | UL Listed | UL 248-12, Class RK5 |
| FLSR_ID | Littelfuse | Class RK5 | Time Delay | .125A-600A | 600 | 300 | UL Listed | UL 248-12, Class RK5 |
| IDSR | Littelfuse | Class RK5 | Time Delay | .100A-600A | 600 | 600 | UL Listed | UL 248-12, Class RK5 |
| TR-R | Mersen | Class RK5 | Time Delay | .100A-600A | 250 | 250/160 | UL Listed | UL 248-12, Class RK5 |
| TRS-R | Mersen | Class RK5 | Time Delay | .100A-600A | 600 | 600/300 | UL Listed | UL 248-12, Class RK5 |
| TRS-RDC | Mersen | Class RK5 | Time Delay | .100A-400A | 300/600 | MSHA | MSHA No. 28-26-0 |
Applications
Instructions of Class RK5 Fuse
Class RK5 Fuse is a current limiting device with a time delay feature. It is rated to interrupt a minimum of 200 Ka and is designed to protect electrical circuits from overloads and shorts.
The Class RK5 fuse features a dual-element construction and is rated at either 250-600 Vdc or 150-600 Vac. The ampere rating range is from 1/10 to 600 amps.
Unlike ordinary fuses, Class RK5 fuses use high melting point alloy materials that quickly melt and open the circuit upon detection of high temperatures. These materials also have low short-circuit resistance, which enables them to quickly cut off short-circuit currents and protect the circuit from damage.
When using a Class RK5 fuse, it is important to choose one that is appropriate for the circuit’s current and operating requirements. To ensure the fuse’s reliability and safety, it should be properly installed and used, and periodically maintained and inspected.
It is also important to note that Class RK5 fuses have a time delay feature, so they should not be used in circuits where the fuse will be energized for an extended period of time, as this can exceed the fuse’s melting time and potentially affect the circuit’s safety and reliability.
Applications of Class RK5 Fuses
- Current limiting
- Service entrance switches
- Helps protect motors against burnout from overloads
- Provides motor overload, ground fault and short-circuit protection
- Switchboard mains and feeders
- Helps protect motors against burnout from single phasing on three-phase systems
- Motor control central mains and motor branch circuits
- All general purpose circuits
