High Voltage DC Relay Contactor 50A YV50

Contact Chamber & Internal Build

• DC arc behaviour — an alternating current arc tends to go out on its own as the waveform crosses zero, while a direct current arc does not, which is the main reason a DC contactor is built differently from an AC switching device.
• Nitrogen-filled chamber — the contact space is filled with high-purity nitrogen rather than air, keeping oxygen and moisture away from the contact faces between switching operations.
• Neodymium-iron-boron magnet — a permanent magnet sits inside the chamber and works with the gas fill to help control the arc created when the circuit is opened under load.
• Sealed body — because the chamber is closed at the factory, the contacts are not exposed to the cabinet atmosphere, so dust and humidity around the installation do not reach them directly.

Mounting & Commissioning

1. Check the space around the mounting position before you drill anything — the contact terminals need clearance for cable bending and for the lugs you plan to use.
2. Fix the switch to a flat, rigid surface inside the enclosure so the coil leads are not carrying the weight of the body.
3. Route the coil leads to the control terminals and leave a short service loop, so the unit can be lifted out later without cutting wires.
4. Land the DC load cables on the contact terminals and tighten them to your own assembly standard.
5. Energise the coil on its own first and confirm the switching action before you close the load circuit — a control-side fault is far easier to trace with no load connected.

Applications

Pre-charge circuits are the classic duty for a high voltage DC relay of this size: the contactor closes ahead of the main switch so a battery pack or capacitor bank can come up to voltage without a damaging inrush. Electric vehicles use the same rating in the battery disconnect and power-distribution path, and charging equipment uses it to isolate the DC output stage at the end of a session. Solar and energy-storage installations switch a battery string or inverter DC link with this frame, often inside an enclosure that sees wide temperature swings. Heating systems and industrial DC power supplies round out the list.

Switching Duty & Endurance

• Mechanical life — the mechanism is rated for 1 x 10⁵ operations, the figure to compare against your test cycles and any automatic switching in the control logic.
• 50 A at 450 VDC — around 1 x 10⁴ operations at this working point, the longest electrical life of the three load conditions.
• 50 A at 750 VDC — endurance falls to roughly 3 x 10³ operations once the same current is switched at the higher voltage.
• 30 A at 1000 VDC — near the top of the voltage window the figure is 5 x 10² operations, so the current has to come down if your system runs at that level.
• Reading the figures — endurance is quoted at three separate load conditions rather than one, so compare the point closest to your own voltage and current instead of assuming the 50 A rating carries the same life at every voltage.

Scale & Supply Capability

YongNeng is a relay manufacturer supplying signal relays, latching relays and high-power relays, together with a high-voltage DC contactor line that runs from 16A up to 400A. Because our range covers everything from light switching duty to heavy DC loads, buyers can consolidate several switching positions with one supplier instead of sourcing each rating separately. Power relays are offered in sealed and open construction, and contact wiring is arranged for straightforward installation. Tell us the current rating, switching duty and mounting space your project needs, and we will help you match the right relay or contactor to your build.

FAQ