C320 – 1 pole bi-directional DC NO contactors up to 1,800 volts

Compact single-pole NO contactors for AC and DC up to 1,800 volts rated insulation voltage. Making current up to 3,000 amps; conventional thermal current up to 1,000 amps; short-time current up to 4,500 amps.

C320K/1000 Ue up to 1.500 V, Ui up to 1,800 V,
Ith = 1,000 A

Design with blowout magnets and arcing chamber.
C320S/1000 Ue up to 60 V, Ui bis 1,800 V,
Ith = 1,000 A.

Main contact system w/o arc chamber.

The bidirectional DC contactors of the C320 series extend the application range of the successful C310 and C360 series. The compact devices switch even higher powers. With a rated short-circuit making capacity of up to 3,000 amps, the contactors are suitable for applications with high inrush currents. The devices can permanently conduct up to 1,000 amps – thanks to high contact forces with measurably less heating in the main contact system. In the event of a short circuit, as much as 4,500 amps may flow for 100 milliseconds without the contacts welding. This means that the contactor retains its full function in order to disconnect large powers when required, regardless of the direction of the current. This excellent breaking capacity is made possible by an efficient ceramic arc chamber with generously dimensioned air gaps.


Compact dimensions — high rated insulation voltage Ui up to 1,800 volts

All air clearances in the contact area are generously dimensioned. The rated insulation voltage is 1,800 volts.
The C320K/1000 is specified for rated operational voltages up to 1,500 volts. The C320S/1000 is suitable for rated operational voltages up to 60 volts and is significantly more compact.

High thermal continuous current Ith up to 1,000 amps

All versions of the C320 can carry up to 1,000 amps permanently. In addition, the series has a very high short-time current carrying capacity Icw up to a maximum of 4,500 amps. These values are achieved by optimised silver contacts, high contact forces and permanently extremely low contact resistances.

High making capacity Icm up to 3,000 amps and an excellent breaking capacity

The C320 can switch on a current of up to 3,000 amps. A PWM controller regulates the coil current, ensures low-bounce switch-on and low holding power. The C320K/1000 handles high short-circuit currents and can switch off a current of 800 amps at 1,500 volts, for example. An efficient ceramic arc chamber makes this very good breaking capacity possible.

Low energy consumption and low heating thanks to sophisticated coil saving circuit

A PWM controller regulates the pull-in and holding current. This ensures a low-bounce switch-on, limits the power consumption in holding mode and significantly reduces the heating of the coil. In addition to flexible and power-saving control, this also increases the service life.

Full bidirectionality — safe disconnection of high powers

All versions of the C320 can reliably disconnect high currents and voltages, irrespective of the current direction. In the C320K/1000, these properties are achieved by the special arrangement of the blowout magnets and arc chamber as well as generously dimensioned air clearances in the contact area.

Auxiliary switches with mirror contact function

The C320 contactors can be equipped with up to four auxiliary switches, of which a maximum of two auxiliary switches can have mirror contact function according to IEC 60947-4-1, Annex F.
Mirror contacts are required for the feedback circuits in safety controls. The mirror contact function means that the NC contact of the auxiliary contact cannot and must not be closed at the same time as the NO main contact.


  • Electrical vehicles, hybrid vehicles and trolley busses
  • DC charging station
  • Battery test system
Rail vehicles
  • Traction contactors for battery or hybrid vehicles
  • Contactors for auxiliary converters for battery or hybrid vehicles
  • Isolating contactors in battery circuits
Battery energy storage systems
  • Grid stabilization and battery energy storages
  • Regenerative systems in industrial plants
  • Battery management systems
  • Home energy storages
  • DC switching in central inverters
  • Electrical cabinet (combiner boxes)
  • Home energy storage systems


C320K/1000, C320S/1000
Type of voltageDC bidirectional
Main contacts, configuration1 NO
Rated operating voltage UeC320K/1000: 1.500 V
C320S/1000: 60 V
Rated insulation voltage Ui1,800 V
Rated impulse withstand voltage Uimp10 kV
Pollution degree
Overvoltage category
Conv. thermal current Ith1,000A @ 60° C
Rated short-time withstand current Icw4,500 A @ t = 100 ms
Breaking capacityC320K/1000: 30 operations @ Ue=1,500 V / Ie = 800 A / L/R: 0,15 ms
C320S/1000: 30 operations @ Ue=60 V / Ie = 2,200 A
(more can be found in the catalogue)
Auxiliary switches4x SPDT max. with mirror contact function, single-break
Snap-action switches S870: AC-15: 230 VAC/1.5 A; DC-13: 60 VDC/0.5 A
Coil voltage Us24 V DC
Coil tolerance16 ... 36 V DC
Mounting orientationhorizontal, vertical
(do not mount upside down)
Temperature range-40° C ... +60° C
Mechanical endurance1,000,000 op. cycles
Show all data

Related Downloads

Catalogue C320
C320 - Bi-directional DC NO contactors for 1,000 A
Manual C320-M
Contactors C320 — Installation and Maintenance Instructions
Safety instructions contactors
AFS / C100 / C110B / C130 / C137 / C152...C159 / C160 / C162 / C163 / C164 / C165 / C193 / C195 / C294 / C295 / C160 / C3xx / C8xx / C400 / C600 / CA / CF / CH / CL / CP / CPP / CS / CT / CU / S100/80 / S132 / S134 / S135 / S005 / S007 / S008 / S306 / S307 / S310
/en/products/contactors/thank-you/C320 – DC bidirectional switchingContactors

Your quick contact to us!

If you have any questions, suggestions or other concerns, please let us know. Please fill out our short contact form.