Fuji Electric SC-03 Contactor Instruction Manual

1. Product Overview

The Fuji Electric SC-03 is a compact motor contactor designed for switching electrical loads in industrial applications. It features a coil operating at 200-220VAC 50Hz or 220-240VAC 60Hz and includes one normally open (N/O) auxiliary contact. This manual provides essential information for the safe and effective use of the SC-03 contactor.

An image of the Fuji Electric SC-03 Contactor, showing its terminals, coil connections (A1, A2), main power terminals (L1, L2, L3), and auxiliary contact (13 NO). Various specifications and certifications are visible on the side labels.

2. Setup and Installation

Installation of the SC-03 contactor should only be performed by qualified personnel in accordance with all local and national electrical codes and regulations. Ensure power is disconnected before beginning any installation work.

• Mounting: Securely mount the contactor in a suitable enclosure, ensuring adequate ventilation and clearance for wiring.
• Coil Wiring: Connect the control voltage (200-220VAC 50Hz or 220-240VAC 60Hz) to the A1 and A2 terminals. Observe correct polarity if applicable, though AC coils are generally non-polar.
• Main Power Wiring: Connect the incoming power supply to terminals L1, L2, and L3. Connect the load to terminals T1, T2, and T3 (often corresponding to 2, 4, 6 or similar markings on the load side). The contactor is rated for 4KW AC3 at 380/440V.
• Auxiliary Contact Wiring: The contactor includes one Normally Open (N/O) auxiliary contact, typically marked 13 NO. This can be used for control circuit feedback or interlocking.
• Wire Type: Use copper (Cu) wire only for all connections.
• Overcurrent Protection: Ensure appropriate overcurrent protection (e.g., fuses or circuit breakers) is installed upstream of the contactor, sized according to the load and local codes. Refer to the instruction sheet for further information on the selection of circuit breakers or fuses.

Always double-check all connections for tightness and correctness before applying power.

3. Operating Instructions

The Fuji Electric SC-03 contactor operates by energizing its coil, which closes the main power contacts and the auxiliary contact. When the coil is de-energized, the contacts return to their open state.

• Activation: Apply the specified control voltage (200-220VAC 50Hz or 220-240VAC 60Hz) to terminals A1 and A2 to energize the coil. This will close the main power contacts (L1-T1, L2-T2, L3-T3) and the normally open auxiliary contact (13 NO).
• Deactivation: Remove the control voltage from terminals A1 and A2 to de-energize the coil. This will open the main power contacts and the auxiliary contact, disconnecting power to the load.
• Auxiliary Contact Use: The 1 N/O auxiliary contact can be integrated into control circuits for status indication, interlocking with other devices, or sequential control.

4. Maintenance

Regular maintenance helps ensure the longevity and reliable operation of the contactor. Always disconnect all power sources before performing any maintenance.

• Visual Inspection: Periodically inspect the contactor for any signs of physical damage, discoloration, or loose connections. Check for dust or debris accumulation.
• Terminal Tightness: Verify that all terminal screws are securely tightened. Loose connections can lead to overheating and component failure.
• Contact Wear: While direct inspection of main contacts may require disassembly, look for signs of excessive arcing or pitting if visible. Replace the contactor if significant wear is observed.
• Cleaning: Use a dry, lint-free cloth to clean the exterior of the contactor. Do not use solvents or abrasive cleaners.

5. Troubleshooting

If the contactor is not functioning as expected, consider the following troubleshooting steps:

• Contactor Does Not Energize:
  • Check if the control voltage (200-220VAC 50Hz / 220-240VAC 60Hz) is present at terminals A1 and A2.
  • Verify that the control circuit is complete and there are no open switches or protective devices.
  • Inspect the coil for damage or open circuits.
• Contactor Energizes but Load Does Not Receive Power:
  • Check the main power supply to terminals L1, L2, L3.
  • Verify that the load is correctly wired to terminals T1, T2, T3.
  • Inspect the main contacts for excessive wear or damage.
  • Check for tripped overcurrent protection devices (fuses, circuit breakers).
• Contactor Overheats:
  • Ensure the load current does not exceed the contactor's rated continuous current (20A).
  • Check for loose connections at the terminals.
  • Verify that the ambient temperature is within the contactor's operating limits.

If issues persist, consult a qualified electrician or contact Fuji Electric technical support.

6. Specifications

7. Warranty and Support

For information regarding the product warranty, please refer to the documentation provided at the time of purchase or contact your seller. For technical support or further inquiries, please visit the official Fuji Electric website or contact their customer service department.

This manual is intended for informational purposes only. Fuji Electric reserves the right to make changes to product specifications without prior notice.