The C303 bi-directional DC contactors are compact, high-performance switchgear for applications with high making currents or large capacities. All versions can carry up to 500 amps continuously; in the event of a short circuit, significantly higher currents can flow without the contacts welding together. This means that the contactor retains its full function to disconnect high loads – up to 1.5 MW – regardless of the current direction. This full bi-directionality is important for systems with a charging and discharging process.
Typical applications are DC circuits in inverters, in battery storage systems or in charging stations in the e-mobility sector.
Small dimensions – great performance! Nevertheless, all the air gaps in the contact area have been generously dimensioned. The rated insulation voltage is 1,500 volts.
The arc chamber of the C303 is made of plastic. This is efficient and saves weight.
All versions of the C303 can permanently carry up to 500 amps – provided a sufficiently dimensioned connection cross-section of 200 mm². The maximum ambient temperature for industrial applications is 80 °C. These excellent values are achieved through very high contact forces.
All versions of the C303 can reliably separate high currents and voltages when required, regardless of the direction of the current. These properties are achieved by the special arrangement of blowout magnets and arc chamber, burn-off resistant silver contacts, high contact forces and generously dimensioned air gaps in the contact area.
The C303 contactors have an auxiliary contact with mirror contact function according to IEC 60947-4-1, annex F. Mirror contacts are required in feedback circuits of safety controls. The mirror contact function informs about the switching state and ensures that the NC contact of the auxiliary contact is not closed at the same time as the NO main contact.
With standard coil and economy circuit for efficient electronic coil control and optimum power consumption when making and holding. Connection via industrial plug.
With optimized coil size to ensure maximum efficiency even without the use of an economy circuit.
With standard coil without economy circuit as precharging contactor for limiting high making currents of the main contactors.
The compact switching device can be integrated especially in areas where there is no space for larger series. Since the C303 series can reliably switch in both directions of current, it is ideally suited for applications with energy recovery. Here, the C303 reliably ensures the galvanic isolation of both poles of the battery from the vehicle’s powertrain in the event of a fault. Areas of application for the C303 series are regenerative systems and DC charging stations or battery test benches. A further application for the use of bi-directional contactors of the C303 series are stationary energy storages. Batteries are charged and discharged regularly. For this purpose it is important that the contactors can switch off safely in both current directions.
Type of voltage | DC bi-directional |
Main contacts, configuration | 1 NO |
Max. switching voltage U | 1,500 V |
Rated insulation voltage Ui | 1,000 V @ PD3 1,500 V @ PD2 |
Rated impulse withstand voltage Uimp | 8 kV |
Pollution degreeOvervoltage category | PD3 OV2 |
Conv. thermal current Ith | 500 A |
Aux. contact | 1x SPDT max. with mirror contact function, single-break Snap-action switch S880: AC-15: 230 VAC/1.0 A; DC-13: 60 VDC/0.5 A |
Coil | Version I: 24 V DC, operating range 10.5 ... 32 V DC, PWM module (integrated) Version E: 24 V DC, operating range 20.4 ... 27.6 V DC, high-efficiency drive |
Vibration | ISO 16750-3: upon request |
Shock | ISO 16750-3: upon request |
Mounting orientation | horizontal, vertical |
Temperature range | –40° C ... +85° C |
Mechanical endurance | 200,000 operations |