50A DC contactor with normally open and normally closed main contact, designed for direct current loads, particularly for electric vehicles, telecommunication equipment, car batteries, trains, ships, and electronic control systems.
Features
- The DC contactor has the characteristics of small size, large load capacity, long service life and simple maintenance, and is very popular among users.
- 50 amps contactor complies with the requirements of the ministry standards JB2286-78, JB3974-85, YD/585-92, YD/T512-92. It has been tested in the factory and by relevant testing units and meets the requirements of the ministry standards. It has been used by users for many years to satisfy users to the maximum extent. Needed, reliable quality.
- 50A DC contactors are suitable for electric forklifts, battery trucks, tractors, excavators, brick making machines, cleaning vehicles, automotive air conditioners, communication power supplies, switch control of electronic control circuits of uninterruptible power supplies, electroplating power supplies and other systems.
Specifications
| Model |
ATO-SZJB50A-D |
ATO-SZJ50A-D |
| Contact Form |
Normally Closed (NC) |
Normally Open (NO) |
| Coil Rated Voltage (DC V) |
12V, 24V, 36V, 48V, 60V, 72V, 84V, 120V, 150V |
| Contact Rated Voltage (DC V) |
≤60V |
| Contact 48V Circuit Rated Load Current (DC-1) |
50A |
| Main Contact Contact Coltage Drop Under 100A Load |
≥80mV |
| Cooling pull-in voltage (V), (20±5)℃ |
≥70% |
| Cooling release operating voltage (V), (20±5)℃ |
≥35%, ≤5% |
| 40℃ Coil Operating Voltage Range |
0.8-1.2Us |
| Power-on Action Time |
10ms |
15ms |
| Power-off Release Time |
25ms |
5ms |
| Maximum Bounce Time of Contact Connection |
10ms |
| Maximum Bounce Time of Contact Disconnection |
3ms |
| Insulation Resistance |
20MΩ |
| Dielectric Strength |
50Hz/60Hz 1000VAC 1minute |
| Maximum Breaking Capacity of Main Contact (Power on for 5ms) |
1000A/5ms at 48V/DC |
600A/5ms at 48V DC |
| Coil Power Consumption (W) |
7-15 |
4-9 |
| Coil Temperature Rise (K) |
≤80 |
≤60 |
| Terminal Temperature Rise (K) |
≤65 |
| Electrical Life |
20000 times |
| Mechanical Life |
300,000 times |
| Work Specifications |
Continuous |
| Contact Material |
Silver Alloy |
| Load Terminal Type |
M5 Screw |
| Coil Terminal Type |
M4 Screw |
| Testing Agency Certification |
CCC, CE, FCC, RoHS |
Load Characteristic Curve

Installation Dimension Diagram

Wiring Diagram & Temperature Rise Curve Graph


Mechanical Capabilities and Usage Environment
| Contact Terminal M8 Tightening Torque (Nm) |
≯4.5 is appropriate |
| Coil Lead-out M4 Tightening Torque (Nm) |
≯1.2 is appropriate |
| Ambient Temperature |
-25~+70℃ |
| Relative Humidity |
+20℃ 98% |
| Vibration Frequency at Fixed Location |
3G, 1~50Hz, amplitude 0.5mm |
| Impact |
(60~100) times/min, acceleration ≤4g |
| Altitude |
2000 meters |
| Installation Direction |
Arbitrary |
| Protection Level |
IP40 (equivalent to IEC60947) |
Tips: Different Functions between contactor and relay
The primary function of a relay is to detect, transmit, convert, or dispose of the signal, it's on-off current is generally small. The relay is usually used in a control circuit to control the weak signal.
The primary function of a contactor is to connect or disconnect the main circuit. The main circuit refers to the one whose working situation is determined by the connection of this circuit. The concept of main circuit corresponds to the control circuit, generally, the current of a main circuit is larger than that of a control circuit.
In general, a contactor with a large capacity is equipped with an arc chute. The contact capacity of a relay will not exceed 5A, that of a midget relay may be 1A or 2A. However, the minimum contact capacity of a contactor could be 9A. Contacts of the contactor usually have three pairs of main contacts (the main contacts are normally open contacts), it also has several pairs of auxiliary contacts.
However, contacts of a relay is generally not divided into main contacts or auxiliary contacts. Sometimes, contacts of a relay are set in pairs, namely the normally open contacts and normally closed contacts are combined, while those of a contactor are not in pairs. As for specific needs, the relay will combine with other equipment into a time relay, a counter, or a pressure relay, which has additional functions, but a contactor doesn't have.