Introduction
This manual provides essential information for the safe and effective use of the Littelfuse CCMR30 Slo-Blow Fuse. The CCMR Series dual-element, time-delay fuses are designed for space-saving protection in motor circuits up to 40 HP. This fuse is rated for 30 Amperes at 600VAC/500VDC.
Image: Littelfuse CCMR30 Slo-Blow Fuse. This image displays the cylindrical fuse with its specifications printed on the body, indicating its voltage and amperage ratings.
Safety Information
WARNING: Electrical shock hazard. Always disconnect power before installing or removing fuses. Only qualified personnel should perform electrical work. Failure to follow these instructions may result in serious injury or death.
- Ensure the fuse rating matches the circuit requirements.
- Do not use damaged fuses.
- Always replace a blown fuse with a fuse of the same type and rating.
- Wear appropriate personal protective equipment (PPE) when working with electrical systems.
Setup and Installation
The Littelfuse CCMR30 fuse is designed for installation in appropriate fuse holders or blocks within electrical panels or equipment.
- Power Disconnection: Before beginning any installation, ensure that all power to the circuit is completely disconnected and locked out according to safety procedures.
- Fuse Holder Preparation: Verify that the fuse holder or block is clean and free from debris. Ensure it is designed to accommodate a 30A, 600V/500V cartridge fuse of dimensions approximately 1.5 x 0.41 x 1.5 inches.
- Insertion: Carefully insert the CCMR30 fuse into the designated fuse holder. Ensure a firm and secure connection. Do not force the fuse into place.
- Verification: Double-check that the fuse is properly seated and that all connections are secure before restoring power.
Operating Principles
The CCMR30 is a Slo-Blow (time-delay) fuse, meaning it is designed to withstand temporary overcurrents without opening, which are common during motor startup or other transient conditions. It will open and interrupt the circuit only when a sustained overcurrent or short-circuit condition occurs, protecting the equipment from damage.
- Current Limiting: This fuse offers extremely current-limiting protection, reducing the peak current and energy let-through during a short circuit, thereby minimizing damage to protected components.
- Interrupting Rating: With an interrupting rating of 200,000A@600Vac, the fuse can safely interrupt very high fault currents.
Maintenance
Fuses are generally maintenance-free devices. However, periodic inspection of the fuse and its holder is recommended as part of a routine electrical system maintenance schedule.
- Visual Inspection: Check for any signs of physical damage, discoloration, or loose connections.
- Replacement: If a fuse has blown (indicated by an open circuit when tested with a multimeter, or sometimes by a visible indicator on certain fuse types), it must be replaced. Always replace with an identical Littelfuse CCMR30 fuse to maintain proper circuit protection.
- Cleaning: Ensure fuse holders are clean to maintain good electrical contact.
Troubleshooting
The primary function of a fuse is to open a circuit when an overcurrent condition occurs. If a fuse blows, it indicates a problem within the protected circuit.
- Fuse Blows Immediately: If a newly installed fuse blows immediately upon power restoration, it suggests a direct short circuit or a severe overload in the system. Do not replace the fuse repeatedly without investigating the cause.
- Intermittent Blowing: If the fuse blows intermittently, it could be due to an intermittent short, a fluctuating overload, or a component nearing its end of life.
- Investigation: Before replacing a blown fuse, always investigate and rectify the cause of the overcurrent. This may involve checking wiring, motor loads, or other electrical components.
- Replacement: Once the fault is cleared, replace the blown fuse with a new Littelfuse CCMR30 fuse.
Specifications
| Feature | Detail |
|---|---|
| Model Number | CCMR030 |
| Amperage Rating | 30 Amps |
| Voltage Rating | 600VAC / 500VDC |
| Fuse Type | Slo-Blow / Time Delay (T) |
| Interrupting Rating | 200,000A @ 600Vac |
| Performance | POWR-PRO, Extremely Current-Limiting |
| Certifications | UL Listed, CSA Certified, RoHS Compliant |
| Material | Copper |
| Product Dimensions | Approximately 1.5 x 0.41 x 1.5 inches |
| Item Weight | 0.32 ounces |
Warranty and Support
For specific warranty information or technical support regarding Littelfuse products, please refer to the official Littelfuse website or contact their customer service directly. This manual does not provide warranty details.
