Power-path switching
Unlike reed relays, HV DC contactors are designed for high-current DC power circuits, isolation and controlled connection/disconnection.
HV DC Contactor
High Voltage DC Contactors for EV, ESS and Industrial DC Systems
SHR AUTOSENSOR HV DC contactors are used for high-voltage DC power switching and isolation in battery packs, charging systems, energy storage, photovoltaic equipment and industrial DC buses.
EV battery packsEnergy storage systemsDC fast chargingMain / precharge contactors
What this component is used for
Precharge coordination
In EV and ESS systems, precharge contactors and resistors limit inrush current before main contactors close.
Safety feedback
Auxiliary contacts, coil control and system interlocks help the controller confirm contactor state in safety-critical systems.
Application details
EV and HEV battery packs
Main positive, main negative and precharge positions connect the battery pack to inverter, charger and DC bus circuits.
Energy storage and solar systems
Used in battery racks, PCS equipment, PV inverters and DC distribution where reliable isolation is required.
Charging infrastructure
Switch high-voltage DC outputs and protect service operations in charging piles and DC fast-charger systems.
Industrial DC buses
Provide isolation and emergency disconnect capability for UPS, motor drives and test benches.
Contactor series at a glance
EVM — ceramic main contactor
Ceramic-brazed, gas-filled chamber for EV main positive/negative disconnect. The hermetic ceramic seal suppresses the DC arc on interruption.
- Up to 1000 VDC
- 100–600 A class
- Hermetic, low arc leakage
ESM — 1500 V energy-storage
Built for battery energy storage, PCS and PV inverters, with the higher 1500 VDC breaking capability these systems use and precharge-ready options.
- Up to 1500 VDC
- 20–800 A class
- ESS / solar optimized
EVG — general-purpose ceramic
Ceramic-sealed general-purpose contactor in a standard industrial footprint, for designs that need gas-filled arc suppression without the flagship EVM specification.
- Up to 1000 VDC
- 150–350 A class
- Cost-effective ceramic
EVI — epoxy industrial
Epoxy-sealed, IP67 contactor for industrial power supplies, UPS and light electric vehicles such as forklifts and golf carts, where extreme arc duty is not the driver.
- Up to 750 VDC
- 30–250 A class
- IP67, cost-effective
Ceramic brazing vs epoxy sealing
Ceramic + gas fill (EVM, ESM, EVG)
The contact chamber is ceramic and brazed to metal for a true hermetic seal, then filled with a hydrogen-based gas mix. This helps interrupt the high-voltage DC arc, prevents contact oxidation, and suits high-current EV/ESS interruption.
Epoxy resin (EVI)
Epoxy encapsulation gives IP67 dust/water protection and high mechanical strength at lower cost. It is the right choice where the DC arc energy is moderate and a hermetic ceramic chamber is not required.
Reading a model code: EVM-200A-12/24V
EVM = ceramic-sealed HV DC contactor family; 200A = nominal current class; 12/24V = coil/control voltage option. Auxiliary contact, coil polarity and busbar terminal arrangement follow the order drawing. Representative starting points: EVI-30A, EVI-100A, EVI-250A, EVM-40A, EVM-200A, EVM-400A.
Selection factors engineers should confirm
- Specify rated voltage, continuous current and making/breaking current under the real DC load.
- Confirm load type: resistive, capacitive, inductive, motor, inverter or fault condition.
- Review precharge sequence, coil economizer/PWM drive and auxiliary contact logic.
- Confirm short-circuit coordination with fuses and BMS protection strategy.
- Check temperature rise, mounting direction, terminal torque and enclosure requirements.
Engineering note: DC interruption is load-dependent and more demanding than AC. Always specify the real circuit, not only nominal voltage and current.
Need help selecting a relay or contactor?
Send voltage, current, load type, coil voltage, package constraints and target application. SHR AUTOSENSOR can recommend a standard series or custom design path.