Flame-Retardant LD Series Connector for Fire Alarm Detectors

PC Series Circular Connector Types and Specifications

Selecting a Fireproof Connector for Fire Alarm Detectors

For fire alarm detectors in building security systems, the primary decision factor is the connector's ability to maintain circuit integrity during a fire event while ensuring reliable signal and power transmission. The flame-retardant LD series connector (IP65) is a suitable choice for this application.

Key Selection Criteria for Fire Alarm Connectors

• Flame Retardancy: The connector shell must be made of a material that self-extinguishes and does not propagate flames. The LD series uses UL94 V-0 grade flame-retardant plastic, which meets this requirement.
• Safety Standards: The material should comply with relevant fire protection standards. The LD series complies with the GB 5135.1 fire protection standard, ensuring it meets building safety regulations.
• Pin Configuration: The connector must support the required circuits. The LD series features 4 pins, which are used for both alarm signal and power supply transmission.
• Maintenance Durability: Regular testing and replacement of detectors require a connector with a long mating life. The LD series offers a plugging life of ≥1000 cycles.
• Environmental Resistance: The connector must withstand building conditions, including vibration and temperature variations. The LD series provides 5g vibration resistance and operates within a temperature range of -20~80℃.

Application Boundaries and Installation Notes

This connector is designed for indoor building environments. Its IP65 rating indicates protection against dust ingress and low-pressure water jets, which is suitable for typical building installations. The 5g vibration resistance is intended to accommodate slight building movements, not continuous high-amplitude vibration from heavy machinery. The temperature range of -20~80℃ covers the typical ambient conditions found on different building floors.

When installing, ensure the connector is properly mated to maintain its IP65 rating. The ≥1000 cycle plugging life supports periodic detector testing and replacement without compromising connection integrity.

Understanding the Electrical and Mechanical Parameters

The 4-pin configuration separates alarm signal transmission from power supply, reducing the risk of interference. The UL94 V-0 rating is a critical parameter; it signifies that the plastic material stops burning within 10 seconds after the ignition source is removed, preventing fire spread through the cable system. The GB 5135.1 compliance confirms the product meets the Chinese national standard for automatic fire alarm systems.

Inquiry Checklist for Your Project

Before specifying this connector, verify the following with your supplier:

• Confirm the exact pin assignment for your detector's alarm signal and power requirements.
• Specify the required cable diameter and termination method (soldering, crimping, or screw terminal).
• Verify the operating temperature range of your specific building environment, especially for unheated areas.
• Request the test report for the UL94 V-0 rating and GB 5135.1 compliance.
• Confirm the IP65 rating is maintained when the connector is fully mated and installed.

For related connector options in building automation, you may also review the protocol compatibility for fan coil control connectors to ensure consistency across your building's control systems.