EVC 250A DC Contactor Eaton

High voltage DC contactor 

Power distribution design and protection requirements for on-board high-voltage systems

The main function of the vehicle mounted high-voltage distribution system is to quickly switch and protect against sudden overload or short circuit currents during use, without causing damage to the system. The traditional protection scheme is generally achieved by using DC contactors and fuses. Under normal working conditions, the system has two main contactors and one pre charging contactor. The main contactor is usually selected as a 250A~300A product, while the pre charging contactor is selected as a 50A product. When working, the pre charging contactor and the main negative contactor are first closed to power the circuit. The purpose of the pre charging resistor in the pre charging circuit is to protect the motor from the impact of instantaneous high current. When the bus capacitor is charged to a certain extent, the main positive contactor closes and the pre charging contactor opens, and the circuit is powered on normally and within the safety control protection range. If the system malfunctions, when a small overload current occurs (currently the data provided by the vehicle factory is below 2000A), due to the inverse time characteristic of the fuse, the action time may be too long or not act. Therefore, the DC contactor is mainly used to cut off. Therefore, the DC contactor also needs to have a certain overload breaking ability and can still make and break normally afterwards. When a short circuit current occurs (currently the maximum data provided by the vehicle factory is about 15KA), due to the inherent characteristics of the DC contactor product, it cannot be reliably broken. Therefore, the fuse needs to quickly respond to cut off the circuit for protection, and the action time is within 5ms. At the same time, during this period, the DC contactor cannot have fusion welding.

1. Basic information

EVC DC square contactor uses highly reliable ceramic sealing technology. Compared with traditional DC contactors, this product series has:

• Complete sealing – The contacts are in a sealed environment with low contact resistance and good stability, which can be used in harsh environments.

• Filling gas – Filling in the arc extinguishing gas to improve the arc extinguishing performance of the product and prevent the contacts from oxidation.

• Magnetic blow-out – Use permanent magnets to blow and pull the arc, increasing the capacity of arc extinguishing.

• Miniaturization – New technology increases the load capacity of same volume

• Fully RoHS compliant – More environmentally friendly

It is one of the most used electronic components in electrical vehicles and charging piles for switching and controlling the DC circuits and the equipment. It has long life, high reliability, small size, low power consumption, electromagnetic compatibility, flame retardancy and fast response.

2. Technical parameters

3. Coil parameters

Remark：

•  U sign is an importantly controlled size；

•  The product is installed with M5 bolts and the locking torque is 3Nm-4Nm；

•  Main contact terminal is installed with M6 bolts and the locking torque is 6Nm-8Nm.

4, Application considerations

When the contactor is connected by one or more conductive copper bars, please ensure that the conductive copper bars are closely connected with the contact end surfaces (multiple copper bars need to ensure that the conductive copper bars with large current are closest to the contact end surfaces, followed by the conductive copper bars with small current), and then the flat washers, spring washers and nuts. Improper connection sequence can cause severe overheating.

5, Related product

EVC- 300A

EVC- 400A

6, Related Fuse

Part Number	FWJ-150A	FWH-150C	EVH-300
Description	1000V, 150A high speed fuse	500VDC, 150A DC fuse	70Vdc fuse, 300A, Breaking capacity 6KA
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