80A-50A auto relay NVF4-3A NVF4-4aC

Product Overview

The NVF4-3A-S80a and NVF4-4aC-S80a are high‑capacity automotive relays designed for heavy‑duty switching in 12V/24V vehicle systems. The NVF4-3A-S80a features a SPST (Normally Open) configuration rated at 80A continuous, ideal for battery main contactors, winches, and high‑current lighting. The NVF4-4aC-S80a offers a SPDT (changeover) or DPST (depending on version) with flexible current ratings of 40A, 50A, or 80A, making it perfect for headlamp dual‑beam control, cooling fan speed switching, and hydraulic pump reversing circuits. Both relays share ultra‑low coil power consumption (0.3–0.43W), fast switching (≤4ms), and high dielectric strength (500Vrms). Their sealed construction (leakage ≤10⁻³ Pa·cm³/s) protects contacts from moisture, dust, and engine‑bay contaminants. As core products in YM’s automotive relay portfolio – which includes Automotive Relay, New Energy Relay, Industrial Power Relay, Latching Relay, and PCB Board Relay – the NVF4 series delivers uncompromised performance for trucks, EVs, agricultural machinery, and off‑road equipment.

Technical Specifications

Coil Parameters (12V/24V Versions)

• Coil power consumption: (0.3–0.43)W – ultra‑low for high‑current relays
• Nominal coil voltage: 12V DC or 24V DC (specify when ordering)
• Pick‑up voltage (max): 75% of nominal
• Drop‑out voltage (min): 10% of nominal
• Coil resistance (12V): 330–480Ω; (24V): 1300–1900Ω (at 25°C)

Contact Ratings – NVF4-3A-S80a (SPST NO)

• Continuous current: 80A at 14V DC (resistive load)
• Inrush current (max): 250A for 10ms
• Initial contact resistance: ≤50mΩ; after life ≤200mΩ

Contact Ratings – NVF4-4aC-S80a (SPDT / DPST)

• Configuration: SPDT (1 Form C) or DPST (2 Form A) – specify when ordering
• Continuous current per contact: 40A, 50A, or 80A (depending on version)
• Inrush current: 150A for 40/50A versions; 250A for 80A version (10ms)
• Initial contact resistance: ≤50mΩ; after life ≤200mΩ

Common Specifications (Both Models)

• Low level switching capability: (10–50)μA, (10–50)mV – 1×10⁵ operations
• Action / release time: ≤4ms (typical ≤3ms)
• Dielectric strength (normal atmosphere): 500Vrms, 50Hz; under low pressure: 250Vrms
• Insulation resistance: >500MΩ (initial); after life >50MΩ
• Weight: <3g – lightweight for high‑power relays
• Sealing (leakage rate): ≤10⁻³ Pa·cm³/s (hermetic, dust‑proof and splash‑proof)
• Operating temperature: -40°C to +85°C
• Vibration resistance: 10g RMS, 10-2000Hz per ISO 16750-3
• Terminal style: 4‑pin (SPST) or 5‑pin (SPDT) – ISO 7588 standard footprint

All parameters validated at 25°C ambient. The NVF4 series meets automotive industry standards for high‑current relays (ISO 7588, SAE J560).

Product Images & Visuals

Above: NVF4-3A-S80a (left) and NVF4-4aC-S80a (right) – heavy‑duty automotive relays. Contact YM for dimensional drawings and wiring diagrams.

Key Features & Advantages for High‑Power Automotive Applications

• Wide current range (40A to 80A continuous): One relay family covers multiple applications – from auxiliary lighting (40A) to main battery disconnect (80A). Reduces inventory complexity.
• Ultra‑low coil power (0.3–0.43W): Minimizes heat generation and allows direct drive from automotive ECUs or microcontrollers – eliminates external coil drivers and improves energy efficiency in hybrid/electric vehicles.
• Hermetic sealing (≤10⁻³ Pa·cm³/s): Protects contacts from moisture, road salt, and engine‑bay contaminants – ensures reliable operation in harsh under‑hood environments, making it a true Reliable High-Power Contactor alternative.
• Fast switching (≤4ms) & high isolation: 500Vrms dielectric strength prevents arc‑over; fast response ideal for PWM control and motor reversing.
• Flexible contact configurations: SPST (80A) for simple on/off, SPDT (40A-80A) for changeover applications (e.g., high/low beam, fan speed), and DPST (dual load switching) – all in the same compact package.
• Compatible with standard sockets: ISO 7588 pin layout allows direct replacement of legacy relays in trucks, buses, and agricultural equipment.

YM’s engineering advantage: The NVF4 series shares magnetic circuit and contact technology with our Military Metal Relay and Polarized Relay families, ensuring consistent performance and long life. Compared to generic high‑current relays, the NVF4 offers 10x longer electrical life at 80A and superior sealing. For complete vehicle power management, YM also provides Latching relay, Solid State Relay, and New Energy Relay solutions – a one‑stop source for automotive and industrial power switching.

How to Select & Install the NVF4 High‑Power Relay – Step by Step

1. Determine required configuration: For simple on/off of a single high‑current load (e.g., winch, battery isolator), choose NVF4-3A-S80a (SPST, 80A). For changeover applications (high/low beam, fan speed), choose NVF4-4aC-S80a (SPDT, 40A-80A). For dual independent loads (e.g., twin headlamps), select DPST version.
2. Check coil voltage: Select 12V or 24V version based on vehicle electrical system (12V for passenger cars, 24V for trucks and heavy equipment).
3. Mounting & wiring: Plug the relay into a standard ISO 7588 socket (4‑pin or 5‑pin). For direct PCB mounting, use the optional bracket. Use appropriate wire gauge: 8‑10 AWG for 80A load circuits, 12‑14 AWG for 40A loads. Connect coil terminals (85, 86) to vehicle power and ground (observe polarity if a suppression diode is present).
4. Load connection (SPST – NVF4-3A-S80a): Connect the battery positive to terminal 30, and the load (e.g., starter solenoid, electric fan) to terminal 87.
5. Load connection (SPDT – NVF4-4aC-S80a): Connect common (30) to power source, normally‑open (87) to load 1 (e.g., high beam), and normally‑closed (87a) to load 2 (e.g., low beam). When coil is energized, power switches from 87a to 87.
6. Functional test: Apply rated coil voltage; verify load switching and measure voltage drop across contacts (<100mV at rated current). De‑energize and confirm proper return.
7. Maintenance: Periodically check for loose terminals or corrosion. The sealed relay requires no internal maintenance.

Pro tip for fleet operators: Use the NVF4-4aC-S80a in cooling fan circuits – the SPDT configuration allows a two‑speed fan control (series resistor bypass) with a single relay, saving space and wiring.

Application Scenarios & Key Buyer Benefits

Typical Automotive & Industrial Applications

• Heavy‑duty trucks & trailers: Main battery disconnect, ABS power relay, trailer lighting (80A SPST) – withstands high inrush from lamps and motors.
• Electric & hybrid vehicles (EV/HEV): DC‑DC converter enable, battery pack isolation, and auxiliary load switching – low coil power extends range.
• Off‑road & agricultural machinery: Hydraulic pump contactors, winch control, and work light switching – sealed against dust and moisture.
• Automotive lighting systems: Dual‑beam headlamp control (SPDT version) – seamlessly switches between low and high beams without external diodes.
• Industrial & marine equipment: Electric trolling motor reversing, hoist control, and generator field excitation – robust contact design for inductive loads.

Direct Value to International Buyers (OEMs, Aftermarket Distributors, Fleet Managers)

• Reduced inventory costs: One relay series (40A-80A) replaces multiple discrete relays – simplifies spare parts management.
• Improved system reliability: Hermetic sealing and low contact resistance eliminate premature failures in wet or dusty environments – lowers warranty claims.
• Energy savings: 0.43W max coil power reduces electrical load – especially beneficial for battery‑electric vehicles.
• Global compliance: RoHS/REACH compliant, ISO 9001:2015 & IATF 16949 certified manufacturing – meets stringent automotive quality standards.

For new vehicle platforms, YM offers customization of coil voltages, contact materials (AgSnO₂ for DC motor loads), and additional suppression (resistor or diode). Engineering samples available for validation.

Certifications & Compliance

• IATF 16949:2016 certified production facility (automotive quality management).
• ISO 16750-3 (mechanical vibration and shock for automotive electrical systems).
• ISO 7588 (road vehicles – electrical/electronic switching devices – relay footprint and pinout).
• SAE J560 (primary and auxiliary lighting connectors for trucks – compatible).
• RoHS 2011/65/EU & REACH (EC 1907/2006) compliant – full material declaration available.

Each NVF4 relay is 100% tested for coil resistance, pick‑up/drop‑out voltage, contact resistance at rated current, dielectric strength, and insulation resistance. Lot traceability per IATF 16949 is maintained. Certificates of Conformance (CoC) are provided with every shipment.

Customization Options

YM supports tailored NVF4 series variants for volume OEM orders. Customizations include:

• Coil voltage: 6V, 12V, 24V, 48V DC – matched to specific vehicle platforms.
• Contact material: AgCdO (standard), AgSnO₂ (for DC motor loads, reduces welding), or AgNi (for AC).
• Sealing level: IP54 (standard), IP67 (waterproof, with silicone seal), or unsealed (for dry interior use).
• Terminal style: Standard ISO blade terminals (quick‑connect), PCB pins, or wire leads with connector.
• Suppression: No suppression (standard), resistor (for low‑EMI), or flyback diode (for DC coil protection).
• Marking: Laser engraving of customer part number, logo, or specifications on the relay cover.

Our engineering team provides free feasibility analysis and samples for qualified programs. Minimum order quantities apply – contact YM with your specification sheet.

Production Process & Quality Assurance (IATF 16949)

YM’s automotive relay production line follows a zero‑defect, fully automated process designed to meet the most stringent automotive industry standards.

• Raw material control: 100% verification of magnetic alloys, contact materials, copper wire, and plastic housings – traceable to batch certificates.
• Coil winding & encapsulation: Precision winding with in‑process resistance monitoring; vacuum encapsulation using UL94 V-0 epoxy.
• Contact assembly in Class 100 cleanroom: High‑speed riveting with vision inspection; dynamic contact force testing to ensure ≤50mΩ resistance.
• Hermetic sealing (optional): Ultrasonic welding or epoxy sealing – 100% leak test for IP67 versions.
• 100% functional test: Automated test systems (ATS) measure pick‑up/drop‑out voltage, operate/release time, contact voltage drop at 40A/50A/80A, and insulation resistance.
• Environmental sample testing: Each lot undergoes thermal shock (-40°C to +125°C, 20 cycles), vibration (10g RMS), and life cycle test (10⁵ cycles at rated load).
• Final documentation: Electrical test records, C of C, and (if required) First Article Inspection (FAI) reports per customer specification.

With decades of experience in Automotive Relay and Industrial Power Relay manufacturing, YM has supplied millions of high‑power relays to global automotive customers. The NVF4 series is built to exceed the reliability expectations of modern vehicles, EVs, and off‑highway equipment.