SZJ400A-D Normally Open DC Contactor

In the field of electrical engineering, a **normally open DC contactor** is an important device that manages the flow of current in a direct current (DC) circuit. This electrical switching device is designed to switch a circuit on and off using electromagnetic principles. By understanding its operating principles, design features, applications, and benefits, one can understand the importance of this component in a variety of industrial and commercial settings.

product details

FEATURES

The normally open DC contactor is an essential component in modern electrical systems, providing a range of features that improve safety, efficiency and reliability. Its ability to effectively control DC circuits makes it an indispensable tool for professionals in a variety of industries. With its high current carrying capacity, fast response speed and durable construction, the normally open DC contactor meets the needs of today's complex electrical applications. As technology continues to advance, the importance of this type of device will only increase, solidifying its role in the future of electrical engineering.

SAYOON MODEL IMPLICATION

SZJ	400A	-D	-S	-□	-□	/□
1	2	3	4	5	6	7

1	Product type
2	Rated current
3	Coil type: None-Double coils structure; D-Single coil structure
4	Auxiliary switch: None-Without auxiliary switch; S-With auxiliary switch
5	Mounting bracket type: None-M Horizontal (default); E-Level embedded; L(N)-Vertical; E1-Level embedded single direction
6	Other function codes
7	Coil rated voltage: 12V, 24V, 36V, 48V, 60V, 72V etc.

Uses

This product have one normally open contact, for electric vehicles, telecommunication equipment, engineering machinery, car batteries, electric forklift trucks, trains, ships, electronic control systems such as uninterruptible power supply.

Technical Parameters: (Version 2.53)

SAYOON Product Type	SZJ400A-D
Contact form	1 NO
Coil Rated voltage (DC V)	6V,12V,24V,36V,48V,60V,72V,84V,120V,150V,220V etc.
Contact voltage (DC V)	≤60V
Rated load current of contact 48V circuit (A)	400A
Typical voltage drop across contacts per 100A	≯80mV
The cooling pull-in voltage at (20±5)℃ (V)	≯70%
The cooling drop-out voltage at (20±5)℃ (V)	≯35%,≮5%
Working voltage range of 40℃ coil	0.8-1.2Us
Drop-out time (n/o contacts to open)	35ms
Pull-in time (n/o contacts to close)	10ms
Maximum bounce time for contact connection	10ms
Maximum bounce time for contact disconnection	3ms
Insulation resistance	20MΩ
Electric strength to resist	50Hz/60Hz 1000VAC 1minute
Typical fault currents which can be ruptured	1500A/5ms at 48V DC
Coil power (W)	9-18
Temperature rise of coil (K)	≤60
Temperature rise on outgoing terminal (K)	≤65
Electrical life	20,000 times
Mechanical life	300,000 times
Work specification	Continuous
Contact material	Ag alloy
Load terminal type	M10 Screw
Coil terminal type	M4 Screw
Auxiliary contact rated load (optional)	2A/48VDC, 5A/24VDC
Testing organization certification	CCC,CE,FCC,RoHS

Note:As regarding to the different using environments of customers which requires different focus of the functions,and in order to improve the comprehensive properties of our products,sayoon may adjust the coil parameters,temperature rise and so on. The above parameters are for reference only, For details, please refer to the guidelines for selection and use of the SAYOON DC contactor.

Load Characteristic Curve

Installation Diagram

Wiring Diagram

Temperature Curve

Mechanical Ability And Use Of The Environment

Contact lead M10 tightening torque (N.m)	≯20.5 appropriate
Coil lead M4 tightening torque (N.m)	≯1.2 appropriate
Ambient temperature	-25~+70℃
Relative humidity	+20℃ 98%
Vibration freq. atthe fixed position	3G, 1～50Hz amplitude 0.5mm
Concussion	(60～100) time/minute、acceleration≤4g
Altitude	2000m
Installation direction	Random
International Protection	IP40 (According IEC60947)

Order Instruction

SAYOON Product Type	SZJ400A-D
U.N.W.	1019g
U.G.W.	1040g
Package QTY.	30PCS
Mounting bracket type	None - M Horizontal (default), E Level Embedded, L (N) Vertical, E1 Level embedded single direction

When ordering, please state the following: name, full model, control coil voltage specification, installation frame type, whether with auxiliary contact, order quantity. For example: DC Contactor SZJ400A-D/24V 100pcs, indicating the load rated current 400A, without auxiliary contact, default mounting bracket, coil control voltage 24V purchase 100pcs. Special voltage specification products, such as user needs can be special order.