What is HEC and why is it considered a breakthrough contactor?

GIGAVAC HEC (High Efficiency Contactor) is the next-generation intelligent switching solution Sensata Technologies launched on 17 July 2025 for 800 V electric vehicles. The breakthrough: as the EV market moves to 800 V architectures for faster charging and higher efficiency, the existing 400 V charging infrastructure remains dominant worldwide. HEC reconfigures the 800 V EV battery on-the-fly between 400 V (parallel) and 800 V (series) modes so the vehicle can charge at both existing 400 V chargers and next-gen 800 V fast chargers — without an expensive DC/DC boost converter. This removes the biggest infrastructure barrier to 800 V EV adoption.

How does HEC work? What does "mechanically synchronised 3 poles" mean?

At the core of HEC are three patent-pending mechanically synchronised high-voltage contactor poles. Each pole controls a separate current path, but the open/close motion of the three poles is mechanically linked — like a gear mechanism. Operating modes: • Series Mode (800 V drive/charge): two 400 V packs in series → 800 V output • Parallel Mode (400 V drive/charge): two packs in parallel → 400 V output, double capacity • Isolation Mode (all open): emergency stop, service and safety • A-only: only pack A active, B isolated • B-only: only pack B active, A isolated Mechanical synchronisation makes a wrong combination physically impossible — even software faults, contact welding or mechanical shock cannot break this guarantee. The result is an inherently safe architecture compared with traditional multi-independent contactor solutions.

What does "without a boost converter" mean? What cost and complexity benefits does it bring?

In traditional 800 V EV architectures a DC/DC boost converter is required for the car to charge at 400 V stations. Drawbacks: • High cost: a boost converter is an expensive component (thousands of dollars) • Extra mass: 10-30 kg added weight → reduced range • Volume: less usable pack space • Thermal management: requires its own cooling • Efficiency loss: 3-5% energy lost during charging • Complexity: extra BMS and control electronics With HEC the approach flips: reconfigure the battery itself. No boost converter is needed because the battery's 400 V/800 V state is changed mechanically by HEC. Component count drops by more than 50%, weight and cost fall, the system simplifies, and overall energy efficiency stays high.

HEC has "five different states" — what advantage does that provide?

HEC delivers five battery-configuration states, covering every EV use-case in a single device: 1. Series Mode (800 V drive/charge) — packs A and B in series → high-voltage fast charge (350 kW+) and high-efficiency driving 2. Parallel Mode (400 V drive/charge) — packs A and B in parallel → existing 400 V infrastructure, double capacity 3. Isolation Mode (open-isolated) — all connections open → e-stop, service, safety 4. A-only — only pack A active, B isolated → battery balancing or limp-home if B fails 5. B-only — only pack B active, A isolated → battery balancing or limp-home if A fails With these five states one HEC handles driving, charging, safety, service and fault-tolerance modes.

What are battery balancing and limp-home mode, and why do they matter?

Battery balancing: modern 800 V EVs typically contain two 400 V packs. Over time packs age at different rates (production tolerances, temperature differences), uneven use creates imbalance, and one pack can degrade faster than the other. With HEC's A-only / B-only modes the imbalanced pack can be charged independently and rebalanced, keeping both packs at the same state of health long-term — extending battery life and lowering warranty cost. Limp-home mode: in traditional 800 V architectures a single pack failure leaves the vehicle unable to drive — the driver is stranded. With HEC the healthy pack can be activated alone so the vehicle keeps moving (at reduced capacity) and reaches a safe location, service station or home. This directly impacts OEM warranty cost and brand reliability.

What does "bistable coil" and "0 W holding power" mean? Why is it so important?

Bistable (latching) coil: traditional contactors use a mono-stable coil that must burn power continuously to stay open or closed. A bistable coil has two stable positions; once switched it needs zero power to hold position. Benefits of HEC's 0 W holding power: • No energy draw: while driving or charging HEC stays engaged but burns no coil power → more range • Negligible heat: no continuous power, no warming → no extra cooling needed • Silent operation: no PWM noise, minimal EMI • Long life: no thermal stress, coil winding does not degrade Traditional contactors typically dissipate 5-15 W of holding power; HEC drops this to zero — meaningful range gain for an EV doing 10,000-15,000 km a year.

What does "inherently safe" mean?

Traditional battery-switching systems use a separate contactor per pole, each driven independently by software. That topology is exposed to short-circuit risks: software errors causing a wrong switching combination, welded contacts (one stays closed while another opens), and mechanical shock that can move contactors to a wrong position. HEC's patent-pending mechanically synchronised design makes these risks physically impossible: • The three poles are mechanically linked like a gear train • A wrong combination cannot physically occur • Software faults, contact welding or mechanical shock cannot break the safety • "Best-in-class safety and reliability" (Sensata's official wording) This directly supports ASIL-D — the highest automotive safety integrity level.

How does HEC relate to Megawatt Charging?

Megawatt Charging (MCS) is the next-gen fast-charge standard for electric trucks and buses, delivering 1 MW (1000 kW) and above. Specs include 1500 Vdc, 3000 A, typically 80% charge in ~20 minutes. HEC's MCS-relevant strengths: • 1000 A+ continuous current — sized for MCS levels • Ultra-low contact resistance (<50 µΩ) — minimal loss even at high current • 3-pole mechanically synchronised design — safe high-power switching • NACS / J3400 compatibility — full integration with the North American MCS infrastructure For heavy-duty electric truck and bus OEMs, HEC delivers 400 V depot charging + 800 V MCS charging in a single device.

What is V2G (Vehicle-to-Grid) and how does HEC fit?

V2G (Vehicle-to-Grid) is a bidirectional power-flow architecture that lets the EV battery feed energy back to the grid. Benefits include grid balancing (EVs acting as a virtual power plant), peak demand management, renewable integration (smoothing solar/wind variability) and revenue for the vehicle owner. HEC's V2G strengths: • 400 V / 800 V intelligent switching — works with V2G stations of either voltage • Bidirectional power flow compatibility — safe in both charge (grid → car) and discharge (car → grid) directions • Battery balancing — A-only / B-only modes manage V2G-induced pack imbalance • ASIL-D position sensor — real-time state monitoring during V2G V2G will become a critical EV-market feature within five years; HEC sits at the centre of that trend.

What are HEC's physical dimensions and mounting features?

Dimensions: 100 × 97 × 71 mm, with 3-pole contactor + position sensor + bistable coil in one device. Connection: busbar termination optimised for high current — direct busbar integration instead of conventional cable terminals. Mounting: panel-mount, integrating directly into the EV power-electronics panel; no cooling required thanks to the bistable coil's negligible heat; hermetically sealed for outdoor and humid environments. Environmental: 25 kA short-circuit withstand (without explosion or fire), 90 g shock withstand (incl. heavy-duty vehicles) and 100,000-cycle mechanical life. The compact footprint makes integration into tight pack spaces easy — critical for premium and performance EVs.

When should I choose HEC over other GIGAVAC families?

Choose by application and architecture level: • HEC: modern 800 V EVs needing 400 V / 800 V intelligent switching, V2G + Megawatt charging integration, ASIL-D functional-safety premium projects. • FaultBreak™: EV main protection + switching in one device (combined fuse + contactor), ISO-26262 compliant — protection-focused. • GTM: V2G-capable ESS, DC fast charging, GTMS glass-to-metal sealing, 1500 Vdc. • HX: 1500 Vdc utility-scale solar and EV truck/bus, EPIC® patented ceramic sealing. • GX: 800 Vdc main EV power contactor, 26 models. • MX: heavy-duty industrial and military (MIL-R-6106). • GV: economical high-performance, many variants. • P: MiniTACTOR™ compact pre-charge and solar. HEC stands out as a stand-alone battery-management solution for 800 V EV platforms designed from 2025 onwards. Pairing HEC + FaultBreak in the same system defines the gold standard for modern EV power architecture.

What are HEC's benefits for EV OEMs?

Strategic benefits for EV OEMs: 1. Architecture simplification: component count drops by 50%+ (no boost converter, no multi-contactor stack, no harness); 3-pole + position sensor + bistable coil in one device. 2. Cost: eliminating the boost converter saves thousands of dollars; the BOM simplifies. 3. Performance: bistable coil increases range; ultra-low contact resistance minimises losses; fast charging on both 400 V and 800 V infrastructure. 4. Safety: inherently safe — short-circuit risk is physically impossible; ASIL-D position sensor for real-time diagnostics; 25 kA short-circuit + 90 g shock withstand. 5. Customer experience: drivers can charge at any 400 V or 800 V station — charge anxiety drops; limp-home minimises stranding risk; battery balancing extends pack life and lowers warranty exposure. Brian Wilkie (Sensata EVP, Vehicle Business): "HEC's launch reflects Sensata's commitment to solving real-world electrification challenges with innovative and efficient solutions. These contactors power safer and more efficient vehicles, making EVs more practical and accelerating the adoption of next-generation platforms."

When did HEC launch and what is the supply situation in Turkey?

Launch timeline: • 17 July 2025: global press release from Sensata Technologies (NYSE: ST), Swindon UK • Late 2025: integration discussions with EV OEMs began • 2026: entry into volume-production projects expected • 2026-2030: target of becoming a standard component on next-gen 800 V EV platforms Sensata positions HEC as a key enabler of modern 800 V EV adoption. Brian Wilkie: "making EVs more practical and accelerating adoption of next-generation platforms." IMB Electric is the authorised distributor of GIGAVAC HEC in Turkey — contact us for stock, pricing and technical support. As a new technology HEC sits in the premium price segment, but boost-converter elimination and architecture simplification make it highly competitive on EV OEM project life-cycle cost. We offer integration engineering, sample supply and volume-production planning to OEM customers.

How can I purchase and evaluate HEC?

As the authorised GIGAVAC HEC distributor in Turkey, IMB Electric offers EV OEM and supplier customers: 1. Sample supply & evaluation: samples per Sensata global stock; test support for 400 V / 800 V switching scenarios; validation of battery balancing and limp-home modes. 2. Technical support: EV power-architecture integration planning; ASIL-D functional-safety assessment; V2G and Megawatt-charging integration consultancy; test-protocol and verification support. 3. Volume-production support: project-based pricing; supply-chain planning; direct coordination with Sensata Technologies. 4. Training & information: technical webinar access; datasheets and application notes. We are happy to build a tailored plan for your OEM and tier-1 projects — please reach us through the Contact section.

B2B · PRODUCT SERIES · SENSATA | GIGAVACREF · IMB · SENSATA | GIGAVAC · HEC

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HEC Series — High-Efficiency EV Contactor With Intelligent 400 V / 800 V Switching

Q: What is V2G (Vehicle-to-Grid) and how does HEC fit?

V2G (Vehicle-to-Grid) is a bidirectional power-flow architecture that lets the EV battery feed energy back to the grid. Benefits include grid balancing (EVs acting as a virtual power plant), peak demand management, renewable integration (smoothing solar/wind variability) and revenue for the vehicle owner. HEC's V2G strengths: • 400 V / 800 V intelligent switching — works with V2G stations of either voltage • Bidirectional power flow compatibility — safe in both charge (grid → car) and discharge (car → grid) directions • Battery balancing — A-only / B-only modes manage V2G-induced pack imbalance • ASIL-D position sensor — real-time state monitoring during V2G V2G will become a critical EV-market feature within five years; HEC sits at the centre of that trend.

Q: What are HEC's physical dimensions and mounting features?

Dimensions: 100 × 97 × 71 mm, with 3-pole contactor + position sensor + bistable coil in one device. Connection: busbar termination optimised for high current — direct busbar integration instead of conventional cable terminals. Mounting: panel-mount, integrating directly into the EV power-electronics panel; no cooling required thanks to the bistable coil's negligible heat; hermetically sealed for outdoor and humid environments. Environmental: 25 kA short-circuit withstand (without explosion or fire), 90 g shock withstand (incl. heavy-duty vehicles) and 100,000-cycle mechanical life. The compact footprint makes integration into tight pack spaces easy — critical for premium and performance EVs.

Sensata 2025 launch · Patent-pending mechanically synchronised 3-pole · 1000 A+ continuous · Bistable coil (0 W hold) · ASIL-D position sensor · 400 V / 800 V intelligent switching

GIGAVAC HEC (High Efficiency Contactor), launched by Sensata Technologies on 17 July 2025, is a breakthrough intelligent contactor that solves the EV industry's 400 V → 800 V transition challenge. Its patent-pending mechanically synchronised three high-voltage poles let 800 V EV batteries safely charge at existing 400 V stations without an expensive boost converter — instantly reconfiguring to Parallel-400 V for charging and Series-800 V for driving. Versus traditional architectures it reduces component count by more than 50%, cutting system weight, volume and assembly complexity.

Beyond standard modes, HEC provides independent access to each 400 V pack (A-only / B-only); battery balancing extends pack life and limp-home mode keeps the vehicle moving even if one pack fails. Mechanical synchronisation makes wrong switching physically impossible under software faults, contact welding or mechanical shock — inherently safe. The bistable coil burns 0 W to hold; ultra-low contact resistance (<50 µΩ) minimises losses; 25 kA short-circuit + 90 g shock withstand and an integrated ASIL-D position sensor deliver real-time diagnostics. Compatible with V2G, Megawatt Charging and NACS / J3400 — one solution for the full modern EV ecosystem.

800 V Next-Generation Electric Vehicles400 V Existing Charging-Infrastructure CompatibilityMegawatt (MW) ChargingV2G (Vehicle-to-Grid)NACS / J3400 Charging StandardBattery BalancingLimp-Home ModePremium & Luxury EVsHeavy-Duty Electric Trucks & BusesAutonomous Driving Platforms

01Intelligent Battery Reconfiguration: 400 V ↔ 800 V
02Continuous Current Capability: 1000 A+
03Bistable Coil (No Holding Power): 0 W
04Integrated Position Sensor: ASIL-D

01OVERVIEW

Series · Parallel · Isolation switching for 800V battery architectures — in a single device.

HEC (High Efficiency Contactor) is a bi-stable DC contactor with mechanically synchronized contacts that dynamically reconfigures two separate 400V battery packs between Series (800V), Parallel (400V) and Isolation modes. A single device delivers dual-mode 400V/800V charging compatibility, battery balancing and limp-home capability, halving the contactor count and removing safety complexity from the system.

SYSTEM VOLTAGE

1000Vdc

Designed for 800V architectures

CONTINUOUS CURRENT

1000A

>500A — 1000A range

SHORT-CIRCUIT

25kA

No fire, no rupture

HOLDING POWER

Bi-stable mechanical design

02OPERATING MODES

5 Distinct Configuration States — In One Device

HEC's patented mechanical interlock physically separates 5 distinct connection states between the two battery packs, making incorrect switching impossible by design.

05 · STATES

MODE	STATE	BUS VOLTAGE	TYPICAL USE
S1	Series	800 Vdc	High-speed driving, 800V DC fast charging
S2	Parallel	400 Vdc	400V charger compatibility, doubled-capacity driving
S3	Isolated	0 V	Service, crash, storage — full galvanic isolation
S4	Pack A only	400 Vdc	Battery balancing, limp-home mode
S5	Pack B only	400 Vdc	Battery balancing, redundancy

03TECHNICAL DOSSIER

Manufacturer Datasheet Values

All values verified against official manufacturer documentation.

ELECTRICAL

System voltage: Up to 1000 Vdc
Continuous current: >500 — 1000 A
Initial contact resistance: ~50 µΩ
Short-circuit withstand: Up to 25 kAno fire / no rupture
Operating voltage: 9 — 16 V
Current draw (moving): <2 A5 A peak
Holding power: 0 W

MECHANICAL & LIFE

Dimensions (LxWxH): 100 × 82 × 71 mm
Weight: <500 g
Operating time: <0.5 s
Mechanical shock: 90 g
Mechanical endurance: 100,000state changes
Temperature range: −40 °C … +85 °C

SAFETY & COMMUNICATION

Position sensing: SENT protocol
Safety (sensor): ASIL C
Safety (with ECU): ASIL D capable
Interlock: Mechanical, patented

ARCHITECTURE

Design: Bi-stablestable in both positions
Contact count: Multiple, mech.-synced
Configuration: 5 statesS1 — S5
Polarity: Bi-directional

04ARCHITECTURE & BENEFITS

Innovative Design Principles

Flexible Multi-Mode Configuration

Beyond standard Series-800V, Parallel-400V and Open-Isolated states, supports single-pack modes (A-only / B-only) for battery balancing and limp-home.

Inherently Safe Mechanical Interlock

A unique mechanical interlock physically prevents incorrect switching, eliminating short-circuit risk at the design level — independent of electronic control.

Robust Automotive Performance

Withstands short-circuit events up to 25 kA and mechanical shocks above 90 g — validated for heavy-duty and automotive-class environments.

50%+ Reduction in System Complexity

Replaces the multi-contactor, busbar, fuse and sensor stack of a traditional topology with a single HEC. No extra cooling or special hardware required.

Zero Holding Power

Bi-stable design draws 0 W in position. Ultra-low ~50 µΩ contact resistance minimises battery energy loss across the powertrain.

ASIL-D Capable Feedback

ASIL-C via the position sensor; ASIL-D functional-safety level achievable with ECU-specific programming. SENT communication protocol.

05COMPARISON

Traditional 400/800V Switching vs. HEC

A classical architecture needs at least 4 separate contactors plus extra busbars and a mechanical interlock chain to perform the same switching duty. HEC collapses that stack into a single device.

ASPECT

LEGACY TOPOLOGY

HEC SINGLE DEVICE

Contactor count

4+ separate contactors

1 device

Mechanical interlock

External, extra hardware

Built-in, patented

Holding power (driving)

Continuous draw

0 W

Switching architecture

Software-dependent sync

Mech.-synced contacts

System weight & volume

High

50%+ reduction

Short-circuit safety

Fuse-dependent

25 kA structural withstand

06TYPICAL APPLICATIONS

Target Industries & Scenarios

400V/800V Switchable BEV Batteries

MW-Class DC Charging Stations

Vehicle-to-Grid (V2G) Systems

Autonomous Driving Power Architectures

Heavy-Duty & Off-Highway Electrification

High-Efficiency Powertrain Platforms

★PRE-PRODUCTION · SAMPLING & ENGINEERING

This series is not yet released as a catalog SKU.

Sensata | Gigavac has not yet released production part numbers for this series, so no configurator table is shown. Contact IMB Electric engineering for the continuous current, coil voltage, and contact arrangement that fits your application — engineering response within one business day.

Request Quote & Sample Datasheet (PDF)

TECHNICAL DIFFERENTIATORS

Why HEC Series?

05 · CATEGORIES

ASIL-D Integrated Safety & Broad Compatibility

ASIL-D compliant position sensor — real-time state monitoring
Direct support for the highest automotive safety level (ISO-26262 ASIL-D).
Compatible with V2G + Megawatt Charging + NACS/J3400 standards
One solution for the entire modern EV and energy ecosystem.

400 V ↔ 800 V Intelligent Reconfiguration

An 800 V EV battery can charge at 400 V stations without a boost converter
Full compatibility between modern 800 V EVs and existing 400 V charging infrastructure.
Three standard configurations: Series-800 V (drive), Parallel-400 V (charge), Isolated-Open (safety)
One device covering drive, charge and safety modes.

Bistable Coil — Zero Holding Power

Bistable (latching) coil — 0 W needed to hold position
Negligible energy draw, more vehicle range.
Ultra-low contact resistance <50 µΩ
Minimum loss, negligible heat, no extra cooling required.

Independent Pack Access (A/B Mode)

A-only or B-only modes isolate each 400 V pack independently
Battery balancing and limp-home mode — extends pack life.
The vehicle keeps moving even if one pack fails
No driver stranding; warranty cost and disruption stay minimal.

Patent-Pending Mechanically Synchronised 3-Pole Design

Three HV poles mechanically synchronised — wrong switching is impossible even on software fault
Inherently safe — no short-circuit risk even with welded contacts or mechanical shock.
Reduces component count by more than 50%
System weight, volume and assembly complexity drop significantly.

DATASHEET · GUIDE · APPLICATION NOTE

HEC Series — Technical Resources

05 · FILES

Datasheets

HEC 3-Pole High-Efficiency EV Contactor Datasheet — 400 V / 800 V intelligent switching, mechanically synchronised, ASIL-D integratedSOON

Launch & Event Materials

Sensata Technologies HEC Official Launch (17 July 2025, Swindon UK)SOON
Sensata HEC Webinar — 400 V / 800 V architecture and charging-infrastructure compatibilitySOON

Selection Guides

GIGAVAC Contactors & Fuses Selection Guide (2026)SOON
Sensata EL Contactor Portfolio Brochure (2025)SOON

FREQUENTLY ASKED QUESTIONS

About the HEC series

14/14

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HEC Series — High-Efficiency EV Contactor With Intelligent 400 V / 800 V Switching

Series · Parallel · Isolation switching for 800V battery architectures — in a single device.

5 Distinct Configuration States — In One Device

Manufacturer Datasheet Values

ELECTRICAL

MECHANICAL & LIFE

SAFETY & COMMUNICATION

ARCHITECTURE

Innovative Design Principles

Flexible Multi-Mode Configuration

Inherently Safe Mechanical Interlock

Robust Automotive Performance

50%+ Reduction in System Complexity

Zero Holding Power

ASIL-D Capable Feedback

Traditional 400/800V Switching vs. HEC

Target Industries & Scenarios

This series is not yet released as a catalog SKU.

Why HEC Series?

ASIL-D Integrated Safety & Broad Compatibility

400 V ↔ 800 V Intelligent Reconfiguration

Bistable Coil — Zero Holding Power

Independent Pack Access (A/B Mode)

Patent-Pending Mechanically Synchronised 3-Pole Design

HEC Series — Technical Resources

Datasheets

Launch & Event Materials

Selection Guides

About the HEC series

Go deeper

GIGAVAC Akıllı Kontaktör Serileri ve GigaFuse

Elektrikli Araç Teknolojilerinde Geleceğin Standartları

Kontaktör ve Yüksek Voltaj Rölesi Seçimi

BMS Topolojileri

Kontaktör Bobin Ekomizeri Nedir?

Ekonomizer Çalışma Prensibi

DC Kontaktörlerde Kontak Yapışması Durumu

Elektrikli Araçlarda Termal Kaçak Nedenli Yangınlar

HEC Series — High-Efficiency EV Contactor With Intelligent 400 V / 800 V Switching

Series · Parallel · Isolation switching for 800V battery architectures — in a single device.

5 Distinct Configuration States — In One Device

Manufacturer Datasheet Values

ELECTRICAL

MECHANICAL & LIFE

SAFETY & COMMUNICATION

ARCHITECTURE

Innovative Design Principles

Flexible Multi-Mode Configuration

Inherently Safe Mechanical Interlock

Robust Automotive Performance

50%+ Reduction in System Complexity

Zero Holding Power

ASIL-D Capable Feedback

Traditional 400/800V Switching vs. HEC

Target Industries & Scenarios

This series is not yet released as a catalog SKU.

Why HEC Series?

ASIL-D Integrated Safety & Broad Compatibility

400 V ↔ 800 V Intelligent Reconfiguration

Bistable Coil — Zero Holding Power

Independent Pack Access (A/B Mode)

Patent-Pending Mechanically Synchronised 3-Pole Design

HEC Series — Technical Resources

Datasheets

Launch & Event Materials

Selection Guides

About the HEC series

01What is HEC and why is it considered a breakthrough contactor?

02How does HEC work? What does "mechanically synchronised 3 poles" mean?

03What does "without a boost converter" mean? What cost and complexity benefits does it bring?

04HEC has "five different states" — what advantage does that provide?

05What are battery balancing and limp-home mode, and why do they matter?

06What does "bistable coil" and "0 W holding power" mean? Why is it so important?

Go deeper

GIGAVAC Akıllı Kontaktör Serileri ve GigaFuse

Elektrikli Araç Teknolojilerinde Geleceğin Standartları

Kontaktör ve Yüksek Voltaj Rölesi Seçimi

BMS Topolojileri

Kontaktör Bobin Ekomizeri Nedir?

Ekonomizer Çalışma Prensibi

DC Kontaktörlerde Kontak Yapışması Durumu

Elektrikli Araçlarda Termal Kaçak Nedenli Yangınlar