JARD T78 T74 TRKM Small Electromagnetic Relay

CONTACT DATA

CHARACTERISTICS

COIL DATA

Notes:

1) All values unspecified are at room temperature.

2) Only typical loads are listed above. Other load specifications can be available upon request.

3) For sealed type, the vent-hole cover should be excised.

Product Overview

The JARD T78/T74 series is a compact, PCB-mounted general-purpose electromagnetic relay, available in 1 Form A (NO), 1 Form B (NC), and 1 Form C (CO) configurations. With a 20A/14VDC switching capability, 1250VA max. switching power, and 0.5kV dielectric strength between coil and contacts, it delivers stable performance. Widely used in automotive electronics, smart home devices, industrial controls, and consumer appliances, it provides reliable solutions for low-power signals to control high-power loads.

Key Features

• High Reliability: Contacts use wear-resistant, arc-resistant alloy material, with over 100,000 electrical operations and 10,000,000 mechanical operations.
• Flexible Compatibility: Optional coil power ratings (0.36W/0.6W/0.8W) and coil voltages (5/9/12/24VDC) suit different drive capabilities.
• Safe & Stable: 0.5kV dielectric strength prevents electrical breakdown; strong contact load capacity ensures jitter-free switching.
• Compact & Efficient: 15.7×12.3×14mm small form factor saves PCB space, ideal for high-density circuit layouts.

Coil Data Specification

• 36W (360mW): High coil resistance, low current, ideal for low-power drive scenarios. For example, the 12V model features 400Ω coil resistance and 30mA operating current.
• 6W (600mW): Moderate power consumption, balancing drive capability and coil heating. The 12V model has 240Ω coil resistance and 50mA operating current.
• 8W (800mW): High coil current, fast pull-in speed, suitable for fast-response applications. The 12V model features 180Ω coil resistance and 70mA operating current. All models specify max. pick-up voltage and min. drop-out voltage to ensure control signal stability.

Working Principle

The relay operates on electromagnetic induction. When rated DC voltage is applied to the coil, it generates a magnetic field that moves the internal armature, switching contact states (NO to NC or vice versa), thus enabling a low-power control signal to indirectly manage a high-power load. When the control signal is removed, the magnetic field collapses, and contacts reset via spring force. The specified pick-up and drop-out voltages prevent misoperation caused by voltage fluctuations.

Materials & Construction

• Housing: Flame-retardant engineering plastic, with excellent high-temperature resistance and insulation, compliant with environmental standards.
• Contacts: High-conductivity alloy material, arc-resistant and wear-resistant, ensuring stable conduction under high currents.
• Terminals: Tin-plated copper, providing reliable PCB soldering and strong oxidation resistance.
• Internal Structure: Sealed design prevents dust and moisture, protecting contacts from contamination and ensuring stability in harsh environments.

OEM/ODM Capabilities

We offer mature OEM/ODM services and support long-term partnerships:

• Customization options include coil voltage, contact configuration, terminal pin forms, and silk-screen logos;
• We support custom model development, prototype validation, and mass production;
• With a complete project management process, we provide full support from initial consultation to delivery, and assist with certification applications for European and American customers to meet diverse application needs.

Production Process

1. Incoming Quality Control: Critical components (contacts, coils, housings) are fully inspected before warehousing;

2. Automated Assembly: Precision equipment handles coil winding, contact riveting, and armature assembly;

3. Multi-stage Testing: Electrical performance, dielectric strength, contact resistance, and coil parameter matching tests are performed;

4. Burn-in Screening: Vacuum sealing followed by aging tests to eliminate defective units;

5. Packaging & Warehousing: Anti-static packaging with traceable batches to ensure consistent quality.

FAQ

What do pick-up and drop-out voltages mean?

Pick-up voltage is the maximum control voltage for stable pull-in, while drop-out voltage is the minimum control voltage for reliable reset. Together, they prevent misoperation caused by voltage fluctuations and ensure control signal stability.

How to choose between different coil power ratings?

The low-power 0.36W model is ideal for battery-powered or low-drive-current applications; 0.6W is a general-purpose option balancing power consumption and drive capability; the high-power 0.8W model features fast pull-in speed, suitable for frequent switching or fast-response scenarios.

Do the products meet European and American safety standards?

Products comply with RoHS environmental standards. We can support applications for UL, TUV, and other certifications upon request. The 0.5kV dielectric strength meets the electrical safety requirements of European and American markets.